

<!--XBRL Document Created with Wdesk from Workiva-->
<!-- -->
<link:linkbase xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodStartLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodStartLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/netLabel" xlink:href="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd#netLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedNetLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedNetLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTerseLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedPeriodEndLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedPeriodEndLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedLabel" xlink:type="simple" />
  <link:roleRef roleURI="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:href="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd#negatedTotalLabel" xlink:type="simple" />
  <link:labelLink xlink:role="http://www.xbrl.org/2003/role/link" xlink:type="extended">
    <link:label id="lab_us-gaap_AccountingPoliciesAbstract_5054190DCC1F992C06B43D8438DF32D7_label_en-US" xlink:label="lab_us-gaap_AccountingPoliciesAbstract_01B480288C1B57B8B58859357A699789" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract_01B480288C1B57B8B58859357A699789" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract_01B480288C1B57B8B58859357A699789" xlink:to="lab_us-gaap_AccountingPoliciesAbstract_01B480288C1B57B8B58859357A699789" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_8E85193076DE43FE6F9D3D8438DF3101_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_04987C3B1BEA51EF94C4F24CD846A46F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_8E85193076DE43FE6F9D3D8438DF3101_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_04987C3B1BEA51EF94C4F24CD846A46F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_04987C3B1BEA51EF94C4F24CD846A46F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_04987C3B1BEA51EF94C4F24CD846A46F" xlink:to="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_04987C3B1BEA51EF94C4F24CD846A46F" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_B6920ED2DFA67EAFE32B3D8438DF2448_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_F1C2EDC0D5715A2E9282D5484217C530" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_B6920ED2DFA67EAFE32B3D8438DF2448_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_F1C2EDC0D5715A2E9282D5484217C530" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_F1C2EDC0D5715A2E9282D5484217C530" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_F1C2EDC0D5715A2E9282D5484217C530" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_F1C2EDC0D5715A2E9282D5484217C530" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesNameDomain_03F7FDF8C579C47438673D8438DF82BE_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain_57297F28EFB0533EB402F5A7E2237233" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesNameDomain_03F7FDF8C579C47438673D8438DF82BE_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain_57297F28EFB0533EB402F5A7E2237233" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_57297F28EFB0533EB402F5A7E2237233" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_57297F28EFB0533EB402F5A7E2237233" xlink:to="lab_us-gaap_AntidilutiveSecuritiesNameDomain_57297F28EFB0533EB402F5A7E2237233" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeStockOptionMember_34D04AEC682E4A8494D63D8438E0C640_verboseLabel_en-US" xlink:label="lab_us-gaap_EmployeeStockOptionMember_DBC7DC022D595BAF9E82C677691F364E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Common stock options</link:label>
    <link:label id="lab_us-gaap_EmployeeStockOptionMember_34D04AEC682E4A8494D63D8438E0C640_label_en-US" xlink:label="lab_us-gaap_EmployeeStockOptionMember_DBC7DC022D595BAF9E82C677691F364E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Stock Option [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EmployeeStockOptionMember" xlink:label="loc_us-gaap_EmployeeStockOptionMember_DBC7DC022D595BAF9E82C677691F364E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeStockOptionMember_DBC7DC022D595BAF9E82C677691F364E" xlink:to="lab_us-gaap_EmployeeStockOptionMember_DBC7DC022D595BAF9E82C677691F364E" xlink:type="arc" />
    <link:label id="lab_us-gaap_RestrictedStockMember_549983AE8568D879E8043D8438E072D3_terseLabel_en-US" xlink:label="lab_us-gaap_RestrictedStockMember_E6479DAC726658529D0C86790973B1BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Restricted shares</link:label>
    <link:label id="lab_us-gaap_RestrictedStockMember_549983AE8568D879E8043D8438E072D3_label_en-US" xlink:label="lab_us-gaap_RestrictedStockMember_E6479DAC726658529D0C86790973B1BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restricted Stock [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RestrictedStockMember" xlink:label="loc_us-gaap_RestrictedStockMember_E6479DAC726658529D0C86790973B1BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestrictedStockMember_E6479DAC726658529D0C86790973B1BE" xlink:to="lab_us-gaap_RestrictedStockMember_E6479DAC726658529D0C86790973B1BE" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_EA57C7A83FA244296C213D8438E0C97D_terseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_E383ABDAD8D45D5D8D3859B30C862A84" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_EA57C7A83FA244296C213D8438E0C97D_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_E383ABDAD8D45D5D8D3859B30C862A84" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_E383ABDAD8D45D5D8D3859B30C862A84" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_E383ABDAD8D45D5D8D3859B30C862A84" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_E383ABDAD8D45D5D8D3859B30C862A84" xlink:type="arc" />
    <link:label id="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_89EFE3BA307E78187DEF3D8438E0C15E_verboseLabel_en-US" xlink:label="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_41F00D72D1785F208B6AF7ACCF6B6F1F" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of potentially dilutive securities</link:label>
    <link:label id="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_89EFE3BA307E78187DEF3D8438E0C15E_label_en-US" xlink:label="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_41F00D72D1785F208B6AF7ACCF6B6F1F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Shares Excluded From Computation Of Earnings Per Share [Abstract]</link:label>
    <link:label id="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_89EFE3BA307E78187DEF3D8438E0C15E_documentation_en-US" xlink:label="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_41F00D72D1785F208B6AF7ACCF6B6F1F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Antidilutive Shares excluded from computation of earnings per share.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract" xlink:label="loc_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_41F00D72D1785F208B6AF7ACCF6B6F1F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_41F00D72D1785F208B6AF7ACCF6B6F1F" xlink:to="lab_oesx_AntidilutiveSharesExcludedFromComputationOfEarningsPerShareAbstract_41F00D72D1785F208B6AF7ACCF6B6F1F" xlink:type="arc" />
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_B2F05BCF5FB8C724D8CD3D8438E093E4_verboseLabel_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_745F5164537550088D4FA4E7108A589D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Potentially dilutive securities outstanding (shares)</link:label>
    <link:label id="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_B2F05BCF5FB8C724D8CD3D8438E093E4_label_en-US" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_745F5164537550088D4FA4E7108A589D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_745F5164537550088D4FA4E7108A589D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_745F5164537550088D4FA4E7108A589D" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_745F5164537550088D4FA4E7108A589D" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionsAbstract_0BA64187A821EA41007406B822764829_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsAbstract_0BA64187A821EA41007406B822764829" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transactions [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaap_RelatedPartyTransactionsAbstract_0BA64187A821EA41007406B822764829" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsAbstract_0BA64187A821EA41007406B822764829" xlink:to="lab_us-gaap_RelatedPartyTransactionsAbstract_0BA64187A821EA41007406B822764829" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Related Party Transactions, by Related Party [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366_label_en-US" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Related Party Transactions, by Related Party [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable_A1582F59E588EF60420506B822760366" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Axis]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C" xlink:to="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis_A632BF8FA083C5900F7406B82276396C" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67_label_en-US" xlink:label="lab_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67" xlink:to="lab_us-gaap_RelatedPartyDomain_6F4B029C1DE55AEAF9A406B82276CA67" xlink:type="arc" />
    <link:label id="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646_terseLabel_en-US" xlink:label="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Entity that Current Director Owns Minority Interest and Serves as Board of Directors Chairman</link:label>
    <link:label id="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646_label_en-US" xlink:label="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity that Current Director Owns Minority Interest and Serves as Board of Directors Chairman [Member]</link:label>
    <link:label id="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646_documentation_en-US" xlink:label="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Entity that Current Director Owns Minority Interest and Serves as Board of Directors Chairman [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember" xlink:label="loc_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646" xlink:to="lab_oesx_EntitythatCurrentDirectorOwnsMinorityInterestandServesasBoardofDirectorsChairmanMember_1641A65D1A2A795EAAD406B822763646" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C" xlink:to="lab_us-gaap_RelatedPartyTransactionLineItems_5D6F0AB27EB60970C4B606B82276891C" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D_terseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Purchases from related party</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction, Purchases from Related Party</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty" xlink:label="loc_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D" xlink:to="lab_us-gaap_RelatedPartyTransactionPurchasesFromRelatedParty_4DA5EF222BEA33D1C9C906B822768E6D" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_738F888A8D432B432DE2A6C145620964_label_en-US" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_DE2444D189E45815970663800BD3BDDD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure of Compensation Related Costs, Share-based Payments [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_DE2444D189E45815970663800BD3BDDD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_DE2444D189E45815970663800BD3BDDD" xlink:to="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract_DE2444D189E45815970663800BD3BDDD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_4ABC422B692874E5685AA6C145620308_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_F7D8E2D370A85A6F88E955AF7CE33D37" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_4ABC422B692874E5685AA6C145620308_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_F7D8E2D370A85A6F88E955AF7CE33D37" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_F7D8E2D370A85A6F88E955AF7CE33D37" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_F7D8E2D370A85A6F88E955AF7CE33D37" xlink:to="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTextBlock_F7D8E2D370A85A6F88E955AF7CE33D37" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_4E297DD2DFBE4F27CCD1A6C14562CBC6_terseLabel_en-US" xlink:label="lab_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_1AE5F7ECD3D4563DADC27D0C73EB78CA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of share based payment awards</link:label>
    <link:label id="lab_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_4E297DD2DFBE4F27CCD1A6C14562CBC6_label_en-US" xlink:label="lab_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_1AE5F7ECD3D4563DADC27D0C73EB78CA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock" xlink:label="loc_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_1AE5F7ECD3D4563DADC27D0C73EB78CA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_1AE5F7ECD3D4563DADC27D0C73EB78CA" xlink:to="lab_us-gaap_DisclosureOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTextBlock_1AE5F7ECD3D4563DADC27D0C73EB78CA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_07A38F58427D8CAE8252A6C145624E97_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_60836C610B9650BDB0C4997E099C3358" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of outstanding non-vested stock options</link:label>
    <link:label id="lab_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_07A38F58427D8CAE8252A6C145624E97_label_en-US" xlink:label="lab_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_60836C610B9650BDB0C4997E099C3358" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Nonvested Share Activity [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_60836C610B9650BDB0C4997E099C3358" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_60836C610B9650BDB0C4997E099C3358" xlink:to="lab_us-gaap_ScheduleOfNonvestedShareActivityTableTextBlock_60836C610B9650BDB0C4997E099C3358" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_4AB0ED4522E5A58FCA30A6C14562DB94_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_1E2640BCD6C25440BA555CB4476F368D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of restricted shares granted</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_4AB0ED4522E5A58FCA30A6C14562DB94_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_1E2640BCD6C25440BA555CB4476F368D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_1E2640BCD6C25440BA555CB4476F368D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_1E2640BCD6C25440BA555CB4476F368D" xlink:to="lab_us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_1E2640BCD6C25440BA555CB4476F368D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_26DC5AF5559304EDC61D3CC3A5B789E6_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_58F93E37C01C5FEBAA4F2E9E9860DD02" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_26DC5AF5559304EDC61D3CC3A5B789E6_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_58F93E37C01C5FEBAA4F2E9E9860DD02" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_58F93E37C01C5FEBAA4F2E9E9860DD02" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_58F93E37C01C5FEBAA4F2E9E9860DD02" xlink:to="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable_58F93E37C01C5FEBAA4F2E9E9860DD02" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementLocationAxis_472EAB76BC4C5B6F2CEB3CC3A5B8074B_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationAxis_35F615210E1E5524AF879BBF3C5EDC31" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Statement Location [Axis]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementLocationAxis_472EAB76BC4C5B6F2CEB3CC3A5B8074B_label_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationAxis_35F615210E1E5524AF879BBF3C5EDC31" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement Location [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeStatementLocationAxis" xlink:label="loc_us-gaap_IncomeStatementLocationAxis_35F615210E1E5524AF879BBF3C5EDC31" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementLocationAxis_35F615210E1E5524AF879BBF3C5EDC31" xlink:to="lab_us-gaap_IncomeStatementLocationAxis_35F615210E1E5524AF879BBF3C5EDC31" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementLocationDomain_640F9722276A0C9799E83CC3A5B82ABA_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationDomain_4358BD6BFCE254F2AC40F771B256916C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Statement Location [Domain]</link:label>
    <link:label id="lab_us-gaap_IncomeStatementLocationDomain_640F9722276A0C9799E83CC3A5B82ABA_label_en-US" xlink:label="lab_us-gaap_IncomeStatementLocationDomain_4358BD6BFCE254F2AC40F771B256916C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement Location [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeStatementLocationDomain" xlink:label="loc_us-gaap_IncomeStatementLocationDomain_4358BD6BFCE254F2AC40F771B256916C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementLocationDomain_4358BD6BFCE254F2AC40F771B256916C" xlink:to="lab_us-gaap_IncomeStatementLocationDomain_4358BD6BFCE254F2AC40F771B256916C" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostOfSalesMember_FBEFD008496D93D4BF6C3CC3A5B806A4_verboseLabel_en-US" xlink:label="lab_us-gaap_CostOfSalesMember_93B7CB5C802B5AEA99CA2B92D7541E83" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cost of product revenue</link:label>
    <link:label id="lab_us-gaap_CostOfSalesMember_FBEFD008496D93D4BF6C3CC3A5B806A4_label_en-US" xlink:label="lab_us-gaap_CostOfSalesMember_93B7CB5C802B5AEA99CA2B92D7541E83" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cost of Sales [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_93B7CB5C802B5AEA99CA2B92D7541E83" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfSalesMember_93B7CB5C802B5AEA99CA2B92D7541E83" xlink:to="lab_us-gaap_CostOfSalesMember_93B7CB5C802B5AEA99CA2B92D7541E83" xlink:type="arc" />
    <link:label id="lab_us-gaap_GeneralAndAdministrativeExpenseMember_DD304540A0AF3EE46CA33CC3A5B93040_verboseLabel_en-US" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpenseMember_1B492E4B60095523A32F56D3044051F7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">General and administrative</link:label>
    <link:label id="lab_us-gaap_GeneralAndAdministrativeExpenseMember_DD304540A0AF3EE46CA33CC3A5B93040_label_en-US" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpenseMember_1B492E4B60095523A32F56D3044051F7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">General and Administrative Expense [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_GeneralAndAdministrativeExpenseMember" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpenseMember_1B492E4B60095523A32F56D3044051F7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GeneralAndAdministrativeExpenseMember_1B492E4B60095523A32F56D3044051F7" xlink:to="lab_us-gaap_GeneralAndAdministrativeExpenseMember_1B492E4B60095523A32F56D3044051F7" xlink:type="arc" />
    <link:label id="lab_us-gaap_SellingAndMarketingExpenseMember_5DC084FB5E86F6EFD92F3CC3A5B99358_verboseLabel_en-US" xlink:label="lab_us-gaap_SellingAndMarketingExpenseMember_A19DB725CE905833958205A86D0E89B0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales and marketing</link:label>
    <link:label id="lab_us-gaap_SellingAndMarketingExpenseMember_5DC084FB5E86F6EFD92F3CC3A5B99358_label_en-US" xlink:label="lab_us-gaap_SellingAndMarketingExpenseMember_A19DB725CE905833958205A86D0E89B0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Selling and Marketing Expense [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SellingAndMarketingExpenseMember" xlink:label="loc_us-gaap_SellingAndMarketingExpenseMember_A19DB725CE905833958205A86D0E89B0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingAndMarketingExpenseMember_A19DB725CE905833958205A86D0E89B0" xlink:to="lab_us-gaap_SellingAndMarketingExpenseMember_A19DB725CE905833958205A86D0E89B0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ResearchAndDevelopmentExpenseMember_EC5AE2A997347E7D327A3CC3A5BAF4AF_verboseLabel_en-US" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpenseMember_0868EA4EA08C58029698DC5C215F40D2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Research and development</link:label>
    <link:label id="lab_us-gaap_ResearchAndDevelopmentExpenseMember_EC5AE2A997347E7D327A3CC3A5BAF4AF_label_en-US" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpenseMember_0868EA4EA08C58029698DC5C215F40D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Research and Development Expense [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ResearchAndDevelopmentExpenseMember" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpenseMember_0868EA4EA08C58029698DC5C215F40D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResearchAndDevelopmentExpenseMember_0868EA4EA08C58029698DC5C215F40D2" xlink:to="lab_us-gaap_ResearchAndDevelopmentExpenseMember_0868EA4EA08C58029698DC5C215F40D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_6BEE5C3AFC6F5E7F3D503CC3A5BA6D4A_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_9CF60B4AD4065600BCB07417C8F2F436" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_6BEE5C3AFC6F5E7F3D503CC3A5BA6D4A_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_9CF60B4AD4065600BCB07417C8F2F436" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_9CF60B4AD4065600BCB07417C8F2F436" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_9CF60B4AD4065600BCB07417C8F2F436" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsLineItems_9CF60B4AD4065600BCB07417C8F2F436" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_98516FF7053FC3A48C3D3CC3A5BA47E1_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_4BDF2D2C122F59EBA2DB7C912A2D34D1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_98516FF7053FC3A48C3D3CC3A5BA47E1_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_4BDF2D2C122F59EBA2DB7C912A2D34D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract" xlink:label="loc_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_4BDF2D2C122F59EBA2DB7C912A2D34D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_4BDF2D2C122F59EBA2DB7C912A2D34D1" xlink:to="lab_us-gaap_ShareBasedCompensationAllocationAndClassificationInFinancialStatementsAbstract_4BDF2D2C122F59EBA2DB7C912A2D34D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpense_7F601249E1F0292D73083CC3A5BA5E43_netLabel_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense_75041A8C9FB5596B80FC4542B60FD1E1" xlink:role="http://www.xbrl.org/2009/role/netLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_AllocatedShareBasedCompensationExpense_7F601249E1F0292D73083CC3A5BA5E43_label_en-US" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense_75041A8C9FB5596B80FC4542B60FD1E1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allocated Share-based Compensation Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense_75041A8C9FB5596B80FC4542B60FD1E1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllocatedShareBasedCompensationExpense_75041A8C9FB5596B80FC4542B60FD1E1" xlink:to="lab_us-gaap_AllocatedShareBasedCompensationExpense_75041A8C9FB5596B80FC4542B60FD1E1" xlink:type="arc" />
    <link:label id="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_5A0DB1EF0F6A34B214BDA6C1423D5363_verboseLabel_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_32906CEC17765F57A3470CDC806D8FC5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">RELATED PARTY TRANSACTIONS</link:label>
    <link:label id="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_5A0DB1EF0F6A34B214BDA6C1423D5363_label_en-US" xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_32906CEC17765F57A3470CDC806D8FC5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transactions Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_32906CEC17765F57A3470CDC806D8FC5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_32906CEC17765F57A3470CDC806D8FC5" xlink:to="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock_32906CEC17765F57A3470CDC806D8FC5" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingAbstract_C313BDE7C1303C517261A6C1416608B6_label_en-US" xlink:label="lab_us-gaap_SegmentReportingAbstract_DD79BA9040D95876AEA916EE7D45ED4F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract_DD79BA9040D95876AEA916EE7D45ED4F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingAbstract_DD79BA9040D95876AEA916EE7D45ED4F" xlink:to="lab_us-gaap_SegmentReportingAbstract_DD79BA9040D95876AEA916EE7D45ED4F" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingDisclosureTextBlock_4EC0C9C453FE10CB9F06A6C141664C29_verboseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock_7FFDA5FB218E5117B4DE37A5724187EE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SEGMENTS</link:label>
    <link:label id="lab_us-gaap_SegmentReportingDisclosureTextBlock_4EC0C9C453FE10CB9F06A6C141664C29_label_en-US" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock_7FFDA5FB218E5117B4DE37A5724187EE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SegmentReportingDisclosureTextBlock" xlink:label="loc_us-gaap_SegmentReportingDisclosureTextBlock_7FFDA5FB218E5117B4DE37A5724187EE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingDisclosureTextBlock_7FFDA5FB218E5117B4DE37A5724187EE" xlink:to="lab_us-gaap_SegmentReportingDisclosureTextBlock_7FFDA5FB218E5117B4DE37A5724187EE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_39B5FE5C3C9E7032B01A3CC842368CFD_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_2FF4B8FA6E4E5E808EA78CC3C537DBB9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_39B5FE5C3C9E7032B01A3CC842368CFD_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_2FF4B8FA6E4E5E808EA78CC3C537DBB9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable" xlink:label="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_2FF4B8FA6E4E5E808EA78CC3C537DBB9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_2FF4B8FA6E4E5E808EA78CC3C537DBB9" xlink:to="lab_us-gaap_ScheduleOfFinancingReceivableRecordedInvestmentCreditQualityIndicatorTable_2FF4B8FA6E4E5E808EA78CC3C537DBB9" xlink:type="arc" />
    <link:label id="lab_oesx_FinancingReceivableTypeAxis_CEC6154213670AA96D623CC842368AB6_terseLabel_en-US" xlink:label="lab_oesx_FinancingReceivableTypeAxis_02D1F7C6C6B453119495EAA9EBE607A8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable Type [Axis]</link:label>
    <link:label id="lab_oesx_FinancingReceivableTypeAxis_CEC6154213670AA96D623CC842368AB6_label_en-US" xlink:label="lab_oesx_FinancingReceivableTypeAxis_02D1F7C6C6B453119495EAA9EBE607A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Type [Axis]</link:label>
    <link:label id="lab_oesx_FinancingReceivableTypeAxis_CEC6154213670AA96D623CC842368AB6_documentation_en-US" xlink:label="lab_oesx_FinancingReceivableTypeAxis_02D1F7C6C6B453119495EAA9EBE607A8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Financing Receivable Type [Axis]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_FinancingReceivableTypeAxis" xlink:label="loc_oesx_FinancingReceivableTypeAxis_02D1F7C6C6B453119495EAA9EBE607A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_FinancingReceivableTypeAxis_02D1F7C6C6B453119495EAA9EBE607A8" xlink:to="lab_oesx_FinancingReceivableTypeAxis_02D1F7C6C6B453119495EAA9EBE607A8" xlink:type="arc" />
    <link:label id="lab_oesx_FinancingReceivableTypeDomain_127EB8C0D2B8649E921D3CC8423686B9_terseLabel_en-US" xlink:label="lab_oesx_FinancingReceivableTypeDomain_5271083C49325BA289A191B665EE3B13" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivable Type [Domain]</link:label>
    <link:label id="lab_oesx_FinancingReceivableTypeDomain_127EB8C0D2B8649E921D3CC8423686B9_label_en-US" xlink:label="lab_oesx_FinancingReceivableTypeDomain_5271083C49325BA289A191B665EE3B13" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Type [Domain]</link:label>
    <link:label id="lab_oesx_FinancingReceivableTypeDomain_127EB8C0D2B8649E921D3CC8423686B9_documentation_en-US" xlink:label="lab_oesx_FinancingReceivableTypeDomain_5271083C49325BA289A191B665EE3B13" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">[Domain] for Financing Receivable Type [Axis]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_FinancingReceivableTypeDomain" xlink:label="loc_oesx_FinancingReceivableTypeDomain_5271083C49325BA289A191B665EE3B13" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_FinancingReceivableTypeDomain_5271083C49325BA289A191B665EE3B13" xlink:to="lab_oesx_FinancingReceivableTypeDomain_5271083C49325BA289A191B665EE3B13" xlink:type="arc" />
    <link:label id="lab_oesx_NotPastDueMember_306264077EFDAE03194F3CC8423668F6_verboseLabel_en-US" xlink:label="lab_oesx_NotPastDueMember_E5167384B76E501281092F97CB3A273C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Not Past Due</link:label>
    <link:label id="lab_oesx_NotPastDueMember_306264077EFDAE03194F3CC8423668F6_label_en-US" xlink:label="lab_oesx_NotPastDueMember_E5167384B76E501281092F97CB3A273C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Not Past Due [Member]</link:label>
    <link:label id="lab_oesx_NotPastDueMember_306264077EFDAE03194F3CC8423668F6_documentation_en-US" xlink:label="lab_oesx_NotPastDueMember_E5167384B76E501281092F97CB3A273C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Not past due.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_NotPastDueMember" xlink:label="loc_oesx_NotPastDueMember_E5167384B76E501281092F97CB3A273C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_NotPastDueMember_E5167384B76E501281092F97CB3A273C" xlink:to="lab_oesx_NotPastDueMember_E5167384B76E501281092F97CB3A273C" xlink:type="arc" />
    <link:label id="lab_oesx_OneToNinetyDaysMember_09E15B7E38FA0DCAE71D3CC84236DF5E_verboseLabel_en-US" xlink:label="lab_oesx_OneToNinetyDaysMember_BC79615C50105EAF94C57B1FCC5BD1C8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">1-90 days past due</link:label>
    <link:label id="lab_oesx_OneToNinetyDaysMember_09E15B7E38FA0DCAE71D3CC84236DF5E_label_en-US" xlink:label="lab_oesx_OneToNinetyDaysMember_BC79615C50105EAF94C57B1FCC5BD1C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">One To Ninety Days [Member]</link:label>
    <link:label id="lab_oesx_OneToNinetyDaysMember_09E15B7E38FA0DCAE71D3CC84236DF5E_documentation_en-US" xlink:label="lab_oesx_OneToNinetyDaysMember_BC79615C50105EAF94C57B1FCC5BD1C8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">One to ninety days.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_OneToNinetyDaysMember" xlink:label="loc_oesx_OneToNinetyDaysMember_BC79615C50105EAF94C57B1FCC5BD1C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_OneToNinetyDaysMember_BC79615C50105EAF94C57B1FCC5BD1C8" xlink:to="lab_oesx_OneToNinetyDaysMember_BC79615C50105EAF94C57B1FCC5BD1C8" xlink:type="arc" />
    <link:label id="lab_oesx_GreaterThanNinetyDaysMember_353DB45EA7D4D5A2CE923CC8423665B3_verboseLabel_en-US" xlink:label="lab_oesx_GreaterThanNinetyDaysMember_DC44A2425ECB5EDB8224B874DB65D07C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Greater than 90 days past due</link:label>
    <link:label id="lab_oesx_GreaterThanNinetyDaysMember_353DB45EA7D4D5A2CE923CC8423665B3_label_en-US" xlink:label="lab_oesx_GreaterThanNinetyDaysMember_DC44A2425ECB5EDB8224B874DB65D07C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Greater Than Ninety Days [Member]</link:label>
    <link:label id="lab_oesx_GreaterThanNinetyDaysMember_353DB45EA7D4D5A2CE923CC8423665B3_documentation_en-US" xlink:label="lab_oesx_GreaterThanNinetyDaysMember_DC44A2425ECB5EDB8224B874DB65D07C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Greater than ninety days.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_GreaterThanNinetyDaysMember" xlink:label="loc_oesx_GreaterThanNinetyDaysMember_DC44A2425ECB5EDB8224B874DB65D07C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_GreaterThanNinetyDaysMember_DC44A2425ECB5EDB8224B874DB65D07C" xlink:to="lab_oesx_GreaterThanNinetyDaysMember_DC44A2425ECB5EDB8224B874DB65D07C" xlink:type="arc" />
    <link:label id="lab_oesx_PastDueLeaseNetMember_160C53F48696317DB29A3CC84236C6C8_verboseLabel_en-US" xlink:label="lab_oesx_PastDueLeaseNetMember_D978DBD00BA55CFAAD34B704052A8B43" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total past due</link:label>
    <link:label id="lab_oesx_PastDueLeaseNetMember_160C53F48696317DB29A3CC84236C6C8_label_en-US" xlink:label="lab_oesx_PastDueLeaseNetMember_D978DBD00BA55CFAAD34B704052A8B43" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Past Due Lease Net [Member]</link:label>
    <link:label id="lab_oesx_PastDueLeaseNetMember_160C53F48696317DB29A3CC84236C6C8_documentation_en-US" xlink:label="lab_oesx_PastDueLeaseNetMember_D978DBD00BA55CFAAD34B704052A8B43" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Past due lease net.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_PastDueLeaseNetMember" xlink:label="loc_oesx_PastDueLeaseNetMember_D978DBD00BA55CFAAD34B704052A8B43" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_PastDueLeaseNetMember_D978DBD00BA55CFAAD34B704052A8B43" xlink:to="lab_oesx_PastDueLeaseNetMember_D978DBD00BA55CFAAD34B704052A8B43" xlink:type="arc" />
    <link:label id="lab_oesx_SalesTypeNetMember_009CAF98AEE2696496093CC8423642A7_verboseLabel_en-US" xlink:label="lab_oesx_SalesTypeNetMember_224D1360404952C3A5B159394DDFEE18" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Total sales-type leases</link:label>
    <link:label id="lab_oesx_SalesTypeNetMember_009CAF98AEE2696496093CC8423642A7_label_en-US" xlink:label="lab_oesx_SalesTypeNetMember_224D1360404952C3A5B159394DDFEE18" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales Type Net [Member]</link:label>
    <link:label id="lab_oesx_SalesTypeNetMember_009CAF98AEE2696496093CC8423642A7_documentation_en-US" xlink:label="lab_oesx_SalesTypeNetMember_224D1360404952C3A5B159394DDFEE18" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sales type net.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_SalesTypeNetMember" xlink:label="loc_oesx_SalesTypeNetMember_224D1360404952C3A5B159394DDFEE18" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_SalesTypeNetMember_224D1360404952C3A5B159394DDFEE18" xlink:to="lab_oesx_SalesTypeNetMember_224D1360404952C3A5B159394DDFEE18" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_0B946A6A0D7068779F393CC842378651_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_8D6AE12CA0C8519587063782B4A72028" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable [Line Items]</link:label>
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_0B946A6A0D7068779F393CC842378651_label_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_8D6AE12CA0C8519587063782B4A72028" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsNotesAndLoansReceivableLineItems" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_8D6AE12CA0C8519587063782B4A72028" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableLineItems_8D6AE12CA0C8519587063782B4A72028" xlink:to="lab_us-gaap_AccountsNotesAndLoansReceivableLineItems_8D6AE12CA0C8519587063782B4A72028" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_D520CAD0AAA64D3D77803CC8423708F5_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_1B8574668FFC595FBBEE8DC3932BF559" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Credit quality of the Company's financing receivables using Aging Analysis</link:label>
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_D520CAD0AAA64D3D77803CC8423708F5_label_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_1B8574668FFC595FBBEE8DC3932BF559" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable, Classified [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_1B8574668FFC595FBBEE8DC3932BF559" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_1B8574668FFC595FBBEE8DC3932BF559" xlink:to="lab_us-gaap_AccountsNotesAndLoansReceivableClassifiedAbstract_1B8574668FFC595FBBEE8DC3932BF559" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_705DB75205D07BB08EBC3CC842376DDD_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_F2C1E99E1AEB54BBA78838F8FC1D1954" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Lease balances included in consolidated accounts receivable&#8212;current</link:label>
    <link:label id="lab_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_705DB75205D07BB08EBC3CC842376DDD_label_en-US" xlink:label="lab_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_F2C1E99E1AEB54BBA78838F8FC1D1954" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable, Net, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsNotesAndLoansReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_F2C1E99E1AEB54BBA78838F8FC1D1954" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_F2C1E99E1AEB54BBA78838F8FC1D1954" xlink:to="lab_us-gaap_AccountsNotesAndLoansReceivableNetCurrent_F2C1E99E1AEB54BBA78838F8FC1D1954" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_9B8CBC716124737148ED3CC842373964_verboseLabel_en-US" xlink:label="lab_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_1D49437B4E23515DB3C381FD33B0CF25" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Lease balances included in consolidated accounts receivable&#8212;long-term</link:label>
    <link:label id="lab_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_9B8CBC716124737148ED3CC842373964_label_en-US" xlink:label="lab_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_1D49437B4E23515DB3C381FD33B0CF25" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts, Notes, Loans and Financing Receivable, Net, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent" xlink:label="loc_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_1D49437B4E23515DB3C381FD33B0CF25" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_1D49437B4E23515DB3C381FD33B0CF25" xlink:to="lab_us-gaap_LongTermAccountsNotesAndLoansReceivableNetNoncurrent_1D49437B4E23515DB3C381FD33B0CF25" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableGrossCurrent_7536EB4C3029F7FF20683CC8423751A5_totalLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableGrossCurrent_55513A25CF3458E3AE367B372FB0C410" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total gross sales-type leases</link:label>
    <link:label id="lab_us-gaap_AccountsReceivableGrossCurrent_7536EB4C3029F7FF20683CC8423751A5_label_en-US" xlink:label="lab_us-gaap_AccountsReceivableGrossCurrent_55513A25CF3458E3AE367B372FB0C410" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivable, Gross, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsReceivableGrossCurrent" xlink:label="loc_us-gaap_AccountsReceivableGrossCurrent_55513A25CF3458E3AE367B372FB0C410" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableGrossCurrent_55513A25CF3458E3AE367B372FB0C410" xlink:to="lab_us-gaap_AccountsReceivableGrossCurrent_55513A25CF3458E3AE367B372FB0C410" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_EBE8F0942A18F1B8B15B3CC8423786DA_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_00D19267431A518BBC29B01890F77302" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Allowance</link:label>
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_EBE8F0942A18F1B8B15B3CC8423786DA_label_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_00D19267431A518BBC29B01890F77302" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Allowance for Doubtful Accounts Receivable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_00D19267431A518BBC29B01890F77302" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_00D19267431A518BBC29B01890F77302" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_00D19267431A518BBC29B01890F77302" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableNetCurrent_BADD6B51FBB83192D75D3CC84237B5F4_totalLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent_F6CB5363179157349887512F90FE19DA" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total net sales-type leases</link:label>
    <link:label id="lab_us-gaap_AccountsReceivableNetCurrent_BADD6B51FBB83192D75D3CC84237B5F4_label_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent_F6CB5363179157349887512F90FE19DA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivable, Net, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_F6CB5363179157349887512F90FE19DA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableNetCurrent_F6CB5363179157349887512F90FE19DA" xlink:to="lab_us-gaap_AccountsReceivableNetCurrent_F6CB5363179157349887512F90FE19DA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C1C6F56081A0BB5EB80F4B8153D6DAA6_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1C388C9E6E8B55A187EFB6552618101C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_C1C6F56081A0BB5EB80F4B8153D6DAA6_label_en-US" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1C388C9E6E8B55A187EFB6552618101C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1C388C9E6E8B55A187EFB6552618101C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1C388C9E6E8B55A187EFB6552618101C" xlink:to="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_1C388C9E6E8B55A187EFB6552618101C" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_7B257970ADE33D167DDB4B8153D67987_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_35A04E78A61751788DB003C153B2A52D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_7B257970ADE33D167DDB4B8153D67987_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_35A04E78A61751788DB003C153B2A52D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_35A04E78A61751788DB003C153B2A52D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_35A04E78A61751788DB003C153B2A52D" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis_35A04E78A61751788DB003C153B2A52D" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_1FC703C51D205B2BCC7E4B8153D7C181_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_1F247CA7E28752F5B6E4B88A50C18122" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Domain]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_1FC703C51D205B2BCC7E4B8153D7C181_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_1F247CA7E28752F5B6E4B88A50C18122" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_1F247CA7E28752F5B6E4B88A50C18122" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_1F247CA7E28752F5B6E4B88A50C18122" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain_1F247CA7E28752F5B6E4B88A50C18122" xlink:type="arc" />
    <link:label id="lab_us-gaap_LandImprovementsMember_98756EB985425FBA3B994B8153D70FA6_terseLabel_en-US" xlink:label="lab_us-gaap_LandImprovementsMember_C680927185965529B6487CEA8EEC59CD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Land and land improvements</link:label>
    <link:label id="lab_us-gaap_LandImprovementsMember_98756EB985425FBA3B994B8153D70FA6_label_en-US" xlink:label="lab_us-gaap_LandImprovementsMember_C680927185965529B6487CEA8EEC59CD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Land Improvements [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LandImprovementsMember" xlink:label="loc_us-gaap_LandImprovementsMember_C680927185965529B6487CEA8EEC59CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LandImprovementsMember_C680927185965529B6487CEA8EEC59CD" xlink:to="lab_us-gaap_LandImprovementsMember_C680927185965529B6487CEA8EEC59CD" xlink:type="arc" />
    <link:label id="lab_us-gaap_BuildingAndBuildingImprovementsMember_982918DB74102A80376D4B8153D767C5_verboseLabel_en-US" xlink:label="lab_us-gaap_BuildingAndBuildingImprovementsMember_6FBAF6D7BE135A62AC86BF2F24E865A4" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Buildings and building improvements</link:label>
    <link:label id="lab_us-gaap_BuildingAndBuildingImprovementsMember_982918DB74102A80376D4B8153D767C5_label_en-US" xlink:label="lab_us-gaap_BuildingAndBuildingImprovementsMember_6FBAF6D7BE135A62AC86BF2F24E865A4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Building and Building Improvements [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_BuildingAndBuildingImprovementsMember" xlink:label="loc_us-gaap_BuildingAndBuildingImprovementsMember_6FBAF6D7BE135A62AC86BF2F24E865A4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BuildingAndBuildingImprovementsMember_6FBAF6D7BE135A62AC86BF2F24E865A4" xlink:to="lab_us-gaap_BuildingAndBuildingImprovementsMember_6FBAF6D7BE135A62AC86BF2F24E865A4" xlink:type="arc" />
    <link:label id="lab_us-gaap_FurnitureAndFixturesMember_2CE3E959786560488F954B8153D70C87_verboseLabel_en-US" xlink:label="lab_us-gaap_FurnitureAndFixturesMember_A0B36F6CAC19513885456E589DCC7AB8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Furniture, fixtures and office equipment</link:label>
    <link:label id="lab_us-gaap_FurnitureAndFixturesMember_2CE3E959786560488F954B8153D70C87_label_en-US" xlink:label="lab_us-gaap_FurnitureAndFixturesMember_A0B36F6CAC19513885456E589DCC7AB8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Furniture and Fixtures [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FurnitureAndFixturesMember" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_A0B36F6CAC19513885456E589DCC7AB8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FurnitureAndFixturesMember_A0B36F6CAC19513885456E589DCC7AB8" xlink:to="lab_us-gaap_FurnitureAndFixturesMember_A0B36F6CAC19513885456E589DCC7AB8" xlink:type="arc" />
    <link:label id="lab_us-gaap_LeaseholdImprovementsMember_E4BCACBDCA7EDF60FF2C4B8153D76127_verboseLabel_en-US" xlink:label="lab_us-gaap_LeaseholdImprovementsMember_A38B8E981A3E50AA94F81B36A46E5495" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Leasehold improvements</link:label>
    <link:label id="lab_us-gaap_LeaseholdImprovementsMember_E4BCACBDCA7EDF60FF2C4B8153D76127_label_en-US" xlink:label="lab_us-gaap_LeaseholdImprovementsMember_A38B8E981A3E50AA94F81B36A46E5495" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Leasehold Improvements [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LeaseholdImprovementsMember" xlink:label="loc_us-gaap_LeaseholdImprovementsMember_A38B8E981A3E50AA94F81B36A46E5495" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeaseholdImprovementsMember_A38B8E981A3E50AA94F81B36A46E5495" xlink:to="lab_us-gaap_LeaseholdImprovementsMember_A38B8E981A3E50AA94F81B36A46E5495" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquipmentLeasedToOtherPartyMember_CB2A7B0A0E58D01136194B8153D7D2C5_verboseLabel_en-US" xlink:label="lab_us-gaap_EquipmentLeasedToOtherPartyMember_CD1B66D9244B5735B10D53C1D3F641FA" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equipment leased to customers</link:label>
    <link:label id="lab_us-gaap_EquipmentLeasedToOtherPartyMember_CB2A7B0A0E58D01136194B8153D7D2C5_label_en-US" xlink:label="lab_us-gaap_EquipmentLeasedToOtherPartyMember_CD1B66D9244B5735B10D53C1D3F641FA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equipment Leased to Other Party [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EquipmentLeasedToOtherPartyMember" xlink:label="loc_us-gaap_EquipmentLeasedToOtherPartyMember_CD1B66D9244B5735B10D53C1D3F641FA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquipmentLeasedToOtherPartyMember_CD1B66D9244B5735B10D53C1D3F641FA" xlink:to="lab_us-gaap_EquipmentLeasedToOtherPartyMember_CD1B66D9244B5735B10D53C1D3F641FA" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_A974C65069806D790D9A4B8153D713A0_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_9092A6CDCD6652169E865C481416AF59" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Plant equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_A974C65069806D790D9A4B8153D713A0_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_9092A6CDCD6652169E865C481416AF59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Other Types [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentOtherTypesMember" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_9092A6CDCD6652169E865C481416AF59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_9092A6CDCD6652169E865C481416AF59" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_9092A6CDCD6652169E865C481416AF59" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConstructionInProgressMember_FD7C3CC66B2AA57CE3774B8153D7DC4F_verboseLabel_en-US" xlink:label="lab_us-gaap_ConstructionInProgressMember_DD7C524CF26351EF91E0E1B87D5C9B54" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Construction in progress</link:label>
    <link:label id="lab_us-gaap_ConstructionInProgressMember_FD7C3CC66B2AA57CE3774B8153D7DC4F_label_en-US" xlink:label="lab_us-gaap_ConstructionInProgressMember_DD7C524CF26351EF91E0E1B87D5C9B54" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Construction in Progress [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConstructionInProgressMember" xlink:label="loc_us-gaap_ConstructionInProgressMember_DD7C524CF26351EF91E0E1B87D5C9B54" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConstructionInProgressMember_DD7C524CF26351EF91E0E1B87D5C9B54" xlink:to="lab_us-gaap_ConstructionInProgressMember_DD7C524CF26351EF91E0E1B87D5C9B54" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_10E0D0F9789321EA68D04B8153D7995F_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems_68EF48ABC47458D4A9584A4C01BAE6D6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentLineItems_10E0D0F9789321EA68D04B8153D7995F_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems_68EF48ABC47458D4A9584A4C01BAE6D6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_68EF48ABC47458D4A9584A4C01BAE6D6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_68EF48ABC47458D4A9584A4C01BAE6D6" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentLineItems_68EF48ABC47458D4A9584A4C01BAE6D6" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_4CCE1AD8E14386B962754B8153D78465_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_6B194412E1955E37AEB05D1D40853222" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Property and equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_4CCE1AD8E14386B962754B8153D78465_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_6B194412E1955E37AEB05D1D40853222" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Net [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNetAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNetAbstract_6B194412E1955E37AEB05D1D40853222" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetAbstract_6B194412E1955E37AEB05D1D40853222" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_6B194412E1955E37AEB05D1D40853222" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentGross_54D2B1A0ECA0E1E773764B8153D7084D_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross_9DB8EA73493450DE92455BD995033BFB" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentGross_54D2B1A0ECA0E1E773764B8153D7084D_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross_9DB8EA73493450DE92455BD995033BFB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross_9DB8EA73493450DE92455BD995033BFB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentGross_9DB8EA73493450DE92455BD995033BFB" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentGross_9DB8EA73493450DE92455BD995033BFB" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_E46EA2360F958048268E4B8153D7EBB5_negatedLabel_en-US" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2068434386D35DD39A1E3B90FDC7EAC1" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Less: accumulated depreciation and amortization</link:label>
    <link:label id="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_E46EA2360F958048268E4B8153D7EBB5_label_en-US" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2068434386D35DD39A1E3B90FDC7EAC1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2068434386D35DD39A1E3B90FDC7EAC1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2068434386D35DD39A1E3B90FDC7EAC1" xlink:to="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment_2068434386D35DD39A1E3B90FDC7EAC1" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_27AE3B477E8C5306120A4B8153D70C84_totalLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_A31C87B920BD5205A835BB761711DD6F" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Property and equipment, net</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_27AE3B477E8C5306120A4B8153D70C84_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_A31C87B920BD5205A835BB761711DD6F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_A31C87B920BD5205A835BB761711DD6F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_A31C87B920BD5205A835BB761711DD6F" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet_A31C87B920BD5205A835BB761711DD6F" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityNoteAbstract_88BA84384F5AFCFE51F7A6C1409716B1_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteAbstract_F256F0DFD66C5DC0B4FD0F9C4DBCA325" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Note [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockholdersEquityNoteAbstract" xlink:label="loc_us-gaap_StockholdersEquityNoteAbstract_F256F0DFD66C5DC0B4FD0F9C4DBCA325" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract_F256F0DFD66C5DC0B4FD0F9C4DBCA325" xlink:to="lab_us-gaap_StockholdersEquityNoteAbstract_F256F0DFD66C5DC0B4FD0F9C4DBCA325" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_0C6CB5A36FF7379983ACA6C140984B2A_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_659AAFF3924A5E459506A871D270AA41" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Employee stock purchase plan activity</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_0C6CB5A36FF7379983ACA6C140984B2A_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_659AAFF3924A5E459506A871D270AA41" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_659AAFF3924A5E459506A871D270AA41" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_659AAFF3924A5E459506A871D270AA41" xlink:to="lab_us-gaap_ScheduleOfShareBasedCompensationEmployeeStockPurchasePlanActivityTableTextBlock_659AAFF3924A5E459506A871D270AA41" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtDisclosureAbstract_FCE667F002A2DF46974BA6C1431A21F9_label_en-US" xlink:label="lab_us-gaap_DebtDisclosureAbstract_F049EB584C8A56658966F38358980F41" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract_F049EB584C8A56658966F38358980F41" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureAbstract_F049EB584C8A56658966F38358980F41" xlink:to="lab_us-gaap_DebtDisclosureAbstract_F049EB584C8A56658966F38358980F41" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtTextBlock_B21267A52409EED2A7F5A6C1431A4AB8_verboseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtTextBlock_8D278FF1B3055A3A878E22362A27FA3A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">LONG-TERM DEBT</link:label>
    <link:label id="lab_us-gaap_LongTermDebtTextBlock_B21267A52409EED2A7F5A6C1431A4AB8_label_en-US" xlink:label="lab_us-gaap_LongTermDebtTextBlock_8D278FF1B3055A3A878E22362A27FA3A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermDebtTextBlock" xlink:label="loc_us-gaap_LongTermDebtTextBlock_8D278FF1B3055A3A878E22362A27FA3A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtTextBlock_8D278FF1B3055A3A878E22362A27FA3A" xlink:to="lab_us-gaap_LongTermDebtTextBlock_8D278FF1B3055A3A878E22362A27FA3A" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfCashFlowsAbstract_BE3971FDC1EE6E38B9EC2687B76246CF_label_en-US" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract_BE3971FDC1EE6E38B9EC2687B76246CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract_BE3971FDC1EE6E38B9EC2687B76246CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract_BE3971FDC1EE6E38B9EC2687B76246CF" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract_BE3971FDC1EE6E38B9EC2687B76246CF" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_319D0D79A2C9A53272632687B7654512" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E_verboseLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net loss</link:label>
    <link:label id="lab_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E_label_en-US" xlink:label="lab_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E" xlink:to="lab_us-gaap_NetIncomeLoss_27992F5713D0371CEA3C2687B768AD3E" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089_verboseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Adjustments to reconcile net loss to net cash provided by (used in) operating activities:</link:label>
    <link:label id="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089_label_en-US" xlink:label="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089" xlink:to="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_721FABE02D1FF9623FE12687B769B089" xlink:type="arc" />
    <link:label id="lab_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480_terseLabel_en-US" xlink:label="lab_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Depreciation</link:label>
    <link:label id="lab_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480_label_en-US" xlink:label="lab_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Depreciation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_Depreciation" xlink:label="loc_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480" xlink:to="lab_us-gaap_Depreciation_85C618D0831957FD3EA32687B769C480" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization</link:label>
    <link:label id="lab_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C_label_en-US" xlink:label="lab_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AdjustmentForAmortization" xlink:label="loc_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C" xlink:to="lab_us-gaap_AdjustmentForAmortization_3D8B2C91371FA70F264A2687B769CA6C" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Stock-based compensation</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE" xlink:to="lab_us-gaap_ShareBasedCompensation_42CE7ED854773F8B1A012687B76979BE" xlink:type="arc" />
    <link:label id="lab_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F_negatedLabel_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Loss on sale of property and equipment</link:label>
    <link:label id="lab_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F_label_en-US" xlink:label="lab_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gain (Loss) on Disposition of Property Plant Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_GainLossOnSaleOfPropertyPlantEquipment" xlink:label="loc_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F" xlink:to="lab_us-gaap_GainLossOnSaleOfPropertyPlantEquipment_806421EE677AF5D97ED12687B769275F" xlink:type="arc" />
    <link:label id="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5_terseLabel_en-US" xlink:label="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in inventory reserves</link:label>
    <link:label id="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5_label_en-US" xlink:label="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Provision for inventory reserves</link:label>
    <link:label id="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5_documentation_en-US" xlink:label="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Provision for inventory reserves</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_Provisionforinventoryreserves" xlink:label="loc_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5" xlink:to="lab_oesx_Provisionforinventoryreserves_42C250721DB06DE7F73C2687B769E0C5" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1_verboseLabel_en-US" xlink:label="lab_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Provision for bad debts</link:label>
    <link:label id="lab_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1_label_en-US" xlink:label="lab_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Provision for Doubtful Accounts</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1" xlink:to="lab_us-gaap_ProvisionForDoubtfulAccounts_6F39A5B7AECC274C33B92687B769B2D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519_negatedLabel_en-US" xlink:label="lab_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519_label_en-US" xlink:label="lab_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Noncash Income (Expense)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherNoncashIncomeExpense" xlink:label="loc_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519" xlink:to="lab_us-gaap_OtherNoncashIncomeExpense_A5707DC861B1FCCA30592687B7694519" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in operating assets and liabilities:</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_7889EFFFB606675E2CA72687B76975F8" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable, current and long-term</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accounts Receivable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsReceivable_00763D8F49BE20DA847E2687B7698E06" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Inventories</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Inventories</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0" xlink:to="lab_us-gaap_IncreaseDecreaseInInventories_840A523DD6A3A707E8252687B76AA4C0" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Deferred contract costs</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Deferred Charges</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredCharges" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B" xlink:to="lab_us-gaap_IncreaseDecreaseInDeferredCharges_DA90E1FA9E411726A5EF2687B76AF70B" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B_negatedLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses and other assets</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B" xlink:to="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets_6370D9780B4FFEAC6C612687B76A334B" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140_verboseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts payable</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accounts Payable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsPayable_71283E5C6FB8FB850AD02687B76A9140" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E_verboseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued expenses and other</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accrued Liabilities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_1E02D805031C0C6CD5312687B76AD78E" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6_verboseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred revenue, current and long-term</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Deferred Revenue</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredRevenue" xlink:label="loc_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6" xlink:to="lab_us-gaap_IncreaseDecreaseInDeferredRevenue_6FAC1235F41DC674D0822687B76A1DB6" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) operating activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities_12B3A01D41B872AA4F012687B76A58CA" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Investing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract_2E24059115427CB2B9732687B76A1097" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Purchase of property and equipment</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D" xlink:to="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_B930520D942444745F1D2687B76ABB5D" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E_negatedLabel_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Additions to patents and licenses</link:label>
    <link:label id="lab_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E_label_en-US" xlink:label="lab_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Intangible Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PaymentsToAcquireIntangibleAssets" xlink:label="loc_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E" xlink:to="lab_us-gaap_PaymentsToAcquireIntangibleAssets_ABFA72BEF6FE0B44A71B2687B76A041E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3_verboseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from sales of property, plant and equipment</link:label>
    <link:label id="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3_label_en-US" xlink:label="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Sale of Property, Plant, and Equipment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3" xlink:to="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment_7990CA04FA7B56CC81552687B76A07D3" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) investing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities_D4197B7494FEE240FF272687B76A9A08" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Financing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract_9016B6A86087CD25F8BB2687B76AD9E0" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681_negatedLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Payment of long-term debt and capital leases</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Long-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RepaymentsOfLongTermDebt" xlink:label="loc_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681" xlink:to="lab_us-gaap_RepaymentsOfLongTermDebt_2BADD746E07413E3F30F2687B76A7681" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1_terseLabel_en-US" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from revolving credit facility</link:label>
    <link:label id="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1_label_en-US" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Long-term Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1" xlink:to="lab_us-gaap_ProceedsFromLongTermLinesOfCredit_294F7CA2AD6853A14AA72687B76B3BB1" xlink:type="arc" />
    <link:label id="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payment of revolving credit facility</link:label>
    <link:label id="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE_label_en-US" xlink:label="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Long-term Lines of Credit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit" xlink:label="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE" xlink:to="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit_3004E3E5F95B443483C02687B76BE5EE" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payment of common stock issuance costs</link:label>
    <link:label id="lab_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156_label_en-US" xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Stock Issuance Costs</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156" xlink:to="lab_us-gaap_PaymentsOfStockIssuanceCosts_B26E12A24A2BF1AEF2A22687B76B3156" xlink:type="arc" />
    <link:label id="lab_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Payments to settle employee tax withholdings on stock-based compensation</link:label>
    <link:label id="lab_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338_label_en-US" xlink:label="lab_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments Related to Tax Withholding for Share-based Compensation</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation" xlink:label="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338" xlink:to="lab_us-gaap_PaymentsRelatedToTaxWithholdingForShareBasedCompensation_87855226DB53133CE81B2687B76B1338" xlink:type="arc" />
    <link:label id="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E_terseLabel_en-US" xlink:label="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net proceeds from employee equity exercises</link:label>
    <link:label id="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E_label_en-US" xlink:label="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Exercise of Warrants and Stock Options</link:label>
    <link:label id="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E_documentation_en-US" xlink:label="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds from Exercise of Warrants and Stock Options</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ProceedsfromExerciseofWarrantsandStockOptions" xlink:label="loc_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E" xlink:to="lab_oesx_ProceedsfromExerciseofWarrantsandStockOptions_3C04A0AC1B9B2253163E2687B76B6C2E" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD_totalLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by (used in) financing activities</link:label>
    <link:label id="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities_79C0BFC4BD8F9FCE70E52687B76BA1AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C_totalLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net increase (decrease) in cash and cash equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Period Increase (Decrease)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease" xlink:label="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C" xlink:to="lab_us-gaap_CashAndCashEquivalentsPeriodIncreaseDecrease_A538D92C43036640FA202687B76B591C" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81_periodStartLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents at beginning of period</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, at Carrying Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_CED0EC8126E7F167D9242687B76BFC81" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_8F2C7B36AF15E13D15F82687B76B3EAE_periodEndLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_8F2C7B36AF15E13D15F82687B76B3EAE" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents at end of period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_8F2C7B36AF15E13D15F82687B76B3EAE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_8F2C7B36AF15E13D15F82687B76B3EAE" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_8F2C7B36AF15E13D15F82687B76B3EAE" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnbilledReceivablesCurrent_FDEEFDE226FA60CDA5A13D41141EFD84_terseLabel_en-US" xlink:label="lab_us-gaap_UnbilledReceivablesCurrent_5A7AF689A75455A7BF4CC51007608171" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unbilled accounts receivable</link:label>
    <link:label id="lab_us-gaap_UnbilledReceivablesCurrent_FDEEFDE226FA60CDA5A13D41141EFD84_label_en-US" xlink:label="lab_us-gaap_UnbilledReceivablesCurrent_5A7AF689A75455A7BF4CC51007608171" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unbilled Receivables, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_UnbilledReceivablesCurrent" xlink:label="loc_us-gaap_UnbilledReceivablesCurrent_5A7AF689A75455A7BF4CC51007608171" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnbilledReceivablesCurrent_5A7AF689A75455A7BF4CC51007608171" xlink:to="lab_us-gaap_UnbilledReceivablesCurrent_5A7AF689A75455A7BF4CC51007608171" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherPrepaidExpenseCurrent_EBA013C72800A8348C523D4117FA737B_terseLabel_en-US" xlink:label="lab_us-gaap_OtherPrepaidExpenseCurrent_C2CA6407CF5055509FA24F03EB6124B3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other prepaid expenses</link:label>
    <link:label id="lab_us-gaap_OtherPrepaidExpenseCurrent_EBA013C72800A8348C523D4117FA737B_label_en-US" xlink:label="lab_us-gaap_OtherPrepaidExpenseCurrent_C2CA6407CF5055509FA24F03EB6124B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Prepaid Expense, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherPrepaidExpenseCurrent" xlink:label="loc_us-gaap_OtherPrepaidExpenseCurrent_C2CA6407CF5055509FA24F03EB6124B3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherPrepaidExpenseCurrent_C2CA6407CF5055509FA24F03EB6124B3" xlink:to="lab_us-gaap_OtherPrepaidExpenseCurrent_C2CA6407CF5055509FA24F03EB6124B3" xlink:type="arc" />
    <link:label id="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_9BAE71784FDAA8ADF4383D411BB6046D_totalLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_A25AC2CE1C2A57809F936DF3CAE44AE5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_9BAE71784FDAA8ADF4383D411BB6046D_label_en-US" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_A25AC2CE1C2A57809F936DF3CAE44AE5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expense and Other Assets, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_A25AC2CE1C2A57809F936DF3CAE44AE5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_A25AC2CE1C2A57809F936DF3CAE44AE5" xlink:to="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_A25AC2CE1C2A57809F936DF3CAE44AE5" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of the effect of net income per common share</link:label>
    <link:label id="lab_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C_label_en-US" xlink:label="lab_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C" xlink:to="lab_us-gaap_IncomeStatementAbstract_6F67223E2E612BF8A0FEFC5D33F9C20C" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Numerator:</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share Reconciliation [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerShareReconciliationAbstract" xlink:label="loc_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6" xlink:to="lab_us-gaap_EarningsPerShareReconciliationAbstract_96AEC43F26DE8F590C37FC5D33FAD9E6" xlink:type="arc" />
    <link:label id="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3_verboseLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Denominator:</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract" xlink:label="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3" xlink:to="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustmentAbstract_342320A97800D2122542FC5D33FAFFB3" xlink:type="arc" />
    <link:label id="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B_terseLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average common shares outstanding (in shares)</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_C52DCB3A771F5DADA887FC5D33FA0C9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987_totalLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Weighted-average common shares and common share equivalents outstanding (in shares)</link:label>
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987_label_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987" xlink:to="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_B039D3FEF45184177EB5FC5D33FA2987" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net income (loss) per common share:</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B" xlink:to="lab_us-gaap_EarningsPerShareAbstract_3F99A4CF84218A08FA15FC5D33FA713B" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basic net loss per common share (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Basic</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94" xlink:to="lab_us-gaap_EarningsPerShareBasic_FDE847C1D31B180C3CBFFC5D33FAEB94" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8_terseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Diluted net loss per common share (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8_label_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Diluted</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8" xlink:to="lab_us-gaap_EarningsPerShareDiluted_D94BF901F98F6F784643FC5D33FA3BF8" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward_0E65DFCE80696E19975B901A905B55A8" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9_periodStartLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Non-vested at March 31, 2016 (shares)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_DBAEE9406F2911840A8B901A905B4FA9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Granted (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_94DCB34CD276A4E2A71F901A905B9BF3" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648_negatedLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Vested (shares)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedNumberOfShares_887007EA772B6A7AEB43901A905B4648" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F_negatedLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Forfeited (shares)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_12D20D743ED53B1B727F901A905BD99F" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_3C6CCB96D94A0EC93E22901A905B9056_periodEndLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_3C6CCB96D94A0EC93E22901A905B9056" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Non-vested at September 30, 2016 (shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_3C6CCB96D94A0EC93E22901A905B9056" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_3C6CCB96D94A0EC93E22901A905B9056" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedNumberOfShares_3C6CCB96D94A0EC93E22901A905B9056" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfExtinguishmentOfDebtTable_2A72E747A037AE49B0533CC8412D1C53_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfExtinguishmentOfDebtTable_1831B77AF22950F5B8C19B4C7462EBE9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Extinguishment Of Debt [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfExtinguishmentOfDebtTable_2A72E747A037AE49B0533CC8412D1C53_label_en-US" xlink:label="lab_us-gaap_ScheduleOfExtinguishmentOfDebtTable_1831B77AF22950F5B8C19B4C7462EBE9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Extinguishment of Debt [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfExtinguishmentOfDebtTable" xlink:label="loc_us-gaap_ScheduleOfExtinguishmentOfDebtTable_1831B77AF22950F5B8C19B4C7462EBE9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfExtinguishmentOfDebtTable_1831B77AF22950F5B8C19B4C7462EBE9" xlink:to="lab_us-gaap_ScheduleOfExtinguishmentOfDebtTable_1831B77AF22950F5B8C19B4C7462EBE9" xlink:type="arc" />
    <link:label id="lab_us-gaap_ExtinguishmentOfDebtAxis_CCDA58FABEC11EE103013CC8412DE146_terseLabel_en-US" xlink:label="lab_us-gaap_ExtinguishmentOfDebtAxis_26C4312B816B5D4E8FB47474C4D0CAB2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Extinguishment Of Debt [Axis]</link:label>
    <link:label id="lab_us-gaap_ExtinguishmentOfDebtAxis_CCDA58FABEC11EE103013CC8412DE146_label_en-US" xlink:label="lab_us-gaap_ExtinguishmentOfDebtAxis_26C4312B816B5D4E8FB47474C4D0CAB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Extinguishment of Debt [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ExtinguishmentOfDebtAxis" xlink:label="loc_us-gaap_ExtinguishmentOfDebtAxis_26C4312B816B5D4E8FB47474C4D0CAB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExtinguishmentOfDebtAxis_26C4312B816B5D4E8FB47474C4D0CAB2" xlink:to="lab_us-gaap_ExtinguishmentOfDebtAxis_26C4312B816B5D4E8FB47474C4D0CAB2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ExtinguishmentOfDebtTypeDomain_06B45A1F75506D23C1D93CC8412E8C72_terseLabel_en-US" xlink:label="lab_us-gaap_ExtinguishmentOfDebtTypeDomain_EBB4B291DFB55B0AB3DD3FDE979A2160" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Extinguishment Of Debt Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ExtinguishmentOfDebtTypeDomain_06B45A1F75506D23C1D93CC8412E8C72_label_en-US" xlink:label="lab_us-gaap_ExtinguishmentOfDebtTypeDomain_EBB4B291DFB55B0AB3DD3FDE979A2160" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Extinguishment of Debt, Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ExtinguishmentOfDebtTypeDomain" xlink:label="loc_us-gaap_ExtinguishmentOfDebtTypeDomain_EBB4B291DFB55B0AB3DD3FDE979A2160" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExtinguishmentOfDebtTypeDomain_EBB4B291DFB55B0AB3DD3FDE979A2160" xlink:to="lab_us-gaap_ExtinguishmentOfDebtTypeDomain_EBB4B291DFB55B0AB3DD3FDE979A2160" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevolvingCreditFacilityMember_7E14D2A9FBD33CCCAF6B3CC8412E8730_terseLabel_en-US" xlink:label="lab_us-gaap_RevolvingCreditFacilityMember_98275FA7AEB455099586541BD38DBF9C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revolving credit facility</link:label>
    <link:label id="lab_us-gaap_RevolvingCreditFacilityMember_7E14D2A9FBD33CCCAF6B3CC8412E8730_label_en-US" xlink:label="lab_us-gaap_RevolvingCreditFacilityMember_98275FA7AEB455099586541BD38DBF9C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revolving Credit Facility [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember_98275FA7AEB455099586541BD38DBF9C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevolvingCreditFacilityMember_98275FA7AEB455099586541BD38DBF9C" xlink:to="lab_us-gaap_RevolvingCreditFacilityMember_98275FA7AEB455099586541BD38DBF9C" xlink:type="arc" />
    <link:label id="lab_oesx_HarrisSellersNoteMember_A3AE324AD427C47E90313CC841339C7C_terseLabel_en-US" xlink:label="lab_oesx_HarrisSellersNoteMember_D078DAD4A01950B391A002E451CCB5A2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Harris seller's note</link:label>
    <link:label id="lab_oesx_HarrisSellersNoteMember_A3AE324AD427C47E90313CC841339C7C_label_en-US" xlink:label="lab_oesx_HarrisSellersNoteMember_D078DAD4A01950B391A002E451CCB5A2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Harris Seller's Note [Member]</link:label>
    <link:label id="lab_oesx_HarrisSellersNoteMember_A3AE324AD427C47E90313CC841339C7C_documentation_en-US" xlink:label="lab_oesx_HarrisSellersNoteMember_D078DAD4A01950B391A002E451CCB5A2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Harris Seller's Note [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_HarrisSellersNoteMember" xlink:label="loc_oesx_HarrisSellersNoteMember_D078DAD4A01950B391A002E451CCB5A2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_HarrisSellersNoteMember_D078DAD4A01950B391A002E451CCB5A2" xlink:to="lab_oesx_HarrisSellersNoteMember_D078DAD4A01950B391A002E451CCB5A2" xlink:type="arc" />
    <link:label id="lab_us-gaap_CapitalLeaseObligationsMember_22D0CAE50592188DB6213CC84133F1D4_terseLabel_en-US" xlink:label="lab_us-gaap_CapitalLeaseObligationsMember_0ADAFCA09BCF537FBB3E5AA176FF2B38" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equipment lease obligations</link:label>
    <link:label id="lab_us-gaap_CapitalLeaseObligationsMember_22D0CAE50592188DB6213CC84133F1D4_label_en-US" xlink:label="lab_us-gaap_CapitalLeaseObligationsMember_0ADAFCA09BCF537FBB3E5AA176FF2B38" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Capital Lease Obligations [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CapitalLeaseObligationsMember" xlink:label="loc_us-gaap_CapitalLeaseObligationsMember_0ADAFCA09BCF537FBB3E5AA176FF2B38" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CapitalLeaseObligationsMember_0ADAFCA09BCF537FBB3E5AA176FF2B38" xlink:to="lab_us-gaap_CapitalLeaseObligationsMember_0ADAFCA09BCF537FBB3E5AA176FF2B38" xlink:type="arc" />
    <link:label id="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_CE05BB0242950BF00FCC3CC84133852D_verboseLabel_en-US" xlink:label="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_25EFDCAF6B4B547F86B9B17FCC8A9653" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Customer equipment finance notes payable</link:label>
    <link:label id="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_CE05BB0242950BF00FCC3CC84133852D_label_en-US" xlink:label="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_25EFDCAF6B4B547F86B9B17FCC8A9653" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Customer Equipment Finance Notes Payable [Member]</link:label>
    <link:label id="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_CE05BB0242950BF00FCC3CC84133852D_documentation_en-US" xlink:label="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_25EFDCAF6B4B547F86B9B17FCC8A9653" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Customer equipment finance notes payable.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_CustomerEquipmentFinanceNotesPayableMember" xlink:label="loc_oesx_CustomerEquipmentFinanceNotesPayableMember_25EFDCAF6B4B547F86B9B17FCC8A9653" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_CustomerEquipmentFinanceNotesPayableMember_25EFDCAF6B4B547F86B9B17FCC8A9653" xlink:to="lab_oesx_CustomerEquipmentFinanceNotesPayableMember_25EFDCAF6B4B547F86B9B17FCC8A9653" xlink:type="arc" />
    <link:label id="lab_oesx_OtherLongTermDebtMember_2670720B162179F4700B3CC8413381D8_verboseLabel_en-US" xlink:label="lab_oesx_OtherLongTermDebtMember_18E64D91B06C5FBE9C08F4BA7B080AFB" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other long-term debt</link:label>
    <link:label id="lab_oesx_OtherLongTermDebtMember_2670720B162179F4700B3CC8413381D8_label_en-US" xlink:label="lab_oesx_OtherLongTermDebtMember_18E64D91B06C5FBE9C08F4BA7B080AFB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Long Term Debt [Member]</link:label>
    <link:label id="lab_oesx_OtherLongTermDebtMember_2670720B162179F4700B3CC8413381D8_documentation_en-US" xlink:label="lab_oesx_OtherLongTermDebtMember_18E64D91B06C5FBE9C08F4BA7B080AFB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other long term debt.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_OtherLongTermDebtMember" xlink:label="loc_oesx_OtherLongTermDebtMember_18E64D91B06C5FBE9C08F4BA7B080AFB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_OtherLongTermDebtMember_18E64D91B06C5FBE9C08F4BA7B080AFB" xlink:to="lab_oesx_OtherLongTermDebtMember_18E64D91B06C5FBE9C08F4BA7B080AFB" xlink:type="arc" />
    <link:label id="lab_us-gaap_ExtinguishmentOfDebtLineItems_558337E95DBC472313F03CC841339334_terseLabel_en-US" xlink:label="lab_us-gaap_ExtinguishmentOfDebtLineItems_4B91A819829A5B9585B4A826CFF69A73" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Extinguishment of Debt [Line Items]</link:label>
    <link:label id="lab_us-gaap_ExtinguishmentOfDebtLineItems_558337E95DBC472313F03CC841339334_label_en-US" xlink:label="lab_us-gaap_ExtinguishmentOfDebtLineItems_4B91A819829A5B9585B4A826CFF69A73" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Extinguishment of Debt [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ExtinguishmentOfDebtLineItems" xlink:label="loc_us-gaap_ExtinguishmentOfDebtLineItems_4B91A819829A5B9585B4A826CFF69A73" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExtinguishmentOfDebtLineItems_4B91A819829A5B9585B4A826CFF69A73" xlink:to="lab_us-gaap_ExtinguishmentOfDebtLineItems_4B91A819829A5B9585B4A826CFF69A73" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_F25960BB5791FE356C8C3CC84133A651_verboseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_9A2B469D150C56F39741EF2CC15C28F7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt</link:label>
    <link:label id="lab_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_F25960BB5791FE356C8C3CC84133A651_label_en-US" xlink:label="lab_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_9A2B469D150C56F39741EF2CC15C28F7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, by Current and Noncurrent [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract" xlink:label="loc_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_9A2B469D150C56F39741EF2CC15C28F7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_9A2B469D150C56F39741EF2CC15C28F7" xlink:to="lab_us-gaap_LongTermDebtByCurrentAndNoncurrentAbstract_9A2B469D150C56F39741EF2CC15C28F7" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebt_DE67589BAD34875B5ACC3CC841334F8B_totalLabel_en-US" xlink:label="lab_us-gaap_LongTermDebt_23F4AFB313D2550EAC24457E9C2DF658" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total long-term debt</link:label>
    <link:label id="lab_us-gaap_LongTermDebt_DE67589BAD34875B5ACC3CC841334F8B_label_en-US" xlink:label="lab_us-gaap_LongTermDebt_23F4AFB313D2550EAC24457E9C2DF658" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt_23F4AFB313D2550EAC24457E9C2DF658" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebt_23F4AFB313D2550EAC24457E9C2DF658" xlink:to="lab_us-gaap_LongTermDebt_23F4AFB313D2550EAC24457E9C2DF658" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtCurrent_0B6CA888FAF94D99C3A03CC841334AAF_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_22146F78F18A5FDA9DE8D6AF1FC62626" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Less current maturities</link:label>
    <link:label id="lab_us-gaap_LongTermDebtCurrent_0B6CA888FAF94D99C3A03CC841334AAF_label_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_22146F78F18A5FDA9DE8D6AF1FC62626" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Current Maturities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_22146F78F18A5FDA9DE8D6AF1FC62626" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtCurrent_22146F78F18A5FDA9DE8D6AF1FC62626" xlink:to="lab_us-gaap_LongTermDebtCurrent_22146F78F18A5FDA9DE8D6AF1FC62626" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtNoncurrent_E5610450F5709DD652903CC841346F86_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtNoncurrent_761B4EB8A4A5501AAE0CDC3E01745CEB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt, less current maturities</link:label>
    <link:label id="lab_us-gaap_LongTermDebtNoncurrent_E5610450F5709DD652903CC841346F86_label_en-US" xlink:label="lab_us-gaap_LongTermDebtNoncurrent_761B4EB8A4A5501AAE0CDC3E01745CEB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Excluding Current Maturities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent_761B4EB8A4A5501AAE0CDC3E01745CEB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtNoncurrent_761B4EB8A4A5501AAE0CDC3E01745CEB" xlink:to="lab_us-gaap_LongTermDebtNoncurrent_761B4EB8A4A5501AAE0CDC3E01745CEB" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_BF32F321314170BCA9E1A6C142357F09_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_161D5E555917550CA2C97DD4B9A0648A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_161D5E555917550CA2C97DD4B9A0648A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_161D5E555917550CA2C97DD4B9A0648A" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract_161D5E555917550CA2C97DD4B9A0648A" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_F8B063B67505B4757072A6C142356994_verboseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9F6D3F9C262256EEBFF53264BDD8DE18" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">COMMITMENTS AND CONTINGENCIES</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_F8B063B67505B4757072A6C142356994_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9F6D3F9C262256EEBFF53264BDD8DE18" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9F6D3F9C262256EEBFF53264BDD8DE18" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9F6D3F9C262256EEBFF53264BDD8DE18" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_9F6D3F9C262256EEBFF53264BDD8DE18" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7_label_en-US" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7" xlink:to="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_4C3B3041A0C98F19E6E1901A905586D7" xlink:type="arc" />
    <link:label id="lab_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100_terseLabel_en-US" xlink:label="lab_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Type [Axis]</link:label>
    <link:label id="lab_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100_label_en-US" xlink:label="lab_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Award Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100" xlink:to="lab_us-gaap_AwardTypeAxis_A4300780DAC0D57FB313901A9055F100" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Award Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Award [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1076FDF16276D61632D2901A905594C9" xlink:type="arc" />
    <link:label id="lab_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6_terseLabel_en-US" xlink:label="lab_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Range [Axis]</link:label>
    <link:label id="lab_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6_label_en-US" xlink:label="lab_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Range [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RangeAxis" xlink:label="loc_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6" xlink:to="lab_us-gaap_RangeAxis_D0F9D67699B421B58078901A9055D4B6" xlink:type="arc" />
    <link:label id="lab_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0_terseLabel_en-US" xlink:label="lab_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Range [Domain]</link:label>
    <link:label id="lab_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0_label_en-US" xlink:label="lab_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Range [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RangeMember" xlink:label="loc_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0" xlink:to="lab_us-gaap_RangeMember_91F27FF00AF7C6DB5B60901A9055EFB0" xlink:type="arc" />
    <link:label id="lab_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4_verboseLabel_en-US" xlink:label="lab_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Minimum</link:label>
    <link:label id="lab_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4_label_en-US" xlink:label="lab_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_MinimumMember" xlink:label="loc_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4" xlink:to="lab_us-gaap_MinimumMember_940E1670922C16611BCB901A90551EA4" xlink:type="arc" />
    <link:label id="lab_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE_verboseLabel_en-US" xlink:label="lab_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Maximum</link:label>
    <link:label id="lab_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE_label_en-US" xlink:label="lab_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_MaximumMember" xlink:label="loc_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE" xlink:to="lab_us-gaap_MaximumMember_7A4E2AD49AEA73AE54D4901A9055E6CE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7FC777DD8145530BCEFF901A90566351" xlink:type="arc" />
    <link:label id="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7_verboseLabel_en-US" xlink:label="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of restricted shares granted to key employees</link:label>
    <link:label id="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7_label_en-US" xlink:label="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restricted Shares Issued to Key Employees [Abstract]</link:label>
    <link:label id="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7_documentation_en-US" xlink:label="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restricted shares issued to key employees.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_RestrictedSharesIssuedToKeyEmployeesAbstract" xlink:label="loc_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7" xlink:to="lab_oesx_RestrictedSharesIssuedToKeyEmployeesAbstract_5DAEE926F15C9E339CF4901A9056E5F7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Balance at March 31, 2016 (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_E9C8B3EAF13658C423E7901A905699C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares issued (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_2C1AC6A8BA563B2F1651901A9056FE38" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Shares vested (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod_255B1540C2F9CDE419D8901A9056CC86" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Shares forfeited (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsForfeitedInPeriod_AABB71BBECECC20C883C901A90566141" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_24585428C6982308A719901A9056FFD1_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_24585428C6982308A719901A9056FFD1" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Shares outstanding at September 30, 2016 (shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_24585428C6982308A719901A9056FFD1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_24585428C6982308A719901A9056FFD1" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber_24585428C6982308A719901A9056FFD1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average per share price on grant date (usd per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_A31990FD4EE8A2CC40F2901A90577CA8" xlink:type="arc" />
    <link:label id="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_EF52E75FE38FE258969DA6C144E10BED_label_en-US" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_BC1E4DDAE65556FEA7431D174774B4F0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_BC1E4DDAE65556FEA7431D174774B4F0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_BC1E4DDAE65556FEA7431D174774B4F0" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract_BC1E4DDAE65556FEA7431D174774B4F0" xlink:type="arc" />
    <link:label id="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_36E13A790BC8670EC000A6C144E1C1BC_verboseLabel_en-US" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_C2D660540E135128B0CC90E5CCCD4B45" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">DESCRIPTION OF BUSINESS</link:label>
    <link:label id="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_36E13A790BC8670EC000A6C144E1C1BC_label_en-US" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_C2D660540E135128B0CC90E5CCCD4B45" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_C2D660540E135128B0CC90E5CCCD4B45" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_C2D660540E135128B0CC90E5CCCD4B45" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock_C2D660540E135128B0CC90E5CCCD4B45" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk [Table]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskTable" xlink:label="loc_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619" xlink:to="lab_us-gaap_ConcentrationRiskTable_9042D65F798F216EB18FE2AC19653619" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB_terseLabel_en-US" xlink:label="lab_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segments [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB_label_en-US" xlink:label="lab_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segments [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB" xlink:to="lab_us-gaap_StatementBusinessSegmentsAxis_68A5FA744DD5D5276464E2AC19652BFB" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segments [Domain]</link:label>
    <link:label id="lab_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0_label_en-US" xlink:label="lab_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segments [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0" xlink:to="lab_us-gaap_SegmentDomain_F11F6823C5E09D48B48BE2AC196506A0" xlink:type="arc" />
    <link:label id="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D_terseLabel_en-US" xlink:label="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Orion Engineered Systems</link:label>
    <link:label id="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D_label_en-US" xlink:label="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Engineered Systems [Member]</link:label>
    <link:label id="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D_documentation_en-US" xlink:label="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Engineered Systems Member</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EngineeredSystemsMember" xlink:label="loc_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D" xlink:to="lab_oesx_EngineeredSystemsMember_D77C3E0F4821786D7004E2AC1966B75D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016" xlink:to="lab_us-gaap_ConcentrationRiskByBenchmarkAxis_C2FA1EA32CAEAC325345E2AC19662016" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Domain]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Benchmark [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444" xlink:to="lab_us-gaap_ConcentrationRiskBenchmarkDomain_682FDE432F05A26FF4C0E2AC1966D444" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostOfSalesMember_F2415713967120C37983E2AC196692E5_terseLabel_en-US" xlink:label="lab_us-gaap_CostOfSalesMember_F2415713967120C37983E2AC196692E5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cost of Sales</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CostOfSalesMember" xlink:label="loc_us-gaap_CostOfSalesMember_F2415713967120C37983E2AC196692E5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfSalesMember_F2415713967120C37983E2AC196692E5" xlink:to="lab_us-gaap_CostOfSalesMember_F2415713967120C37983E2AC196692E5" xlink:type="arc" />
    <link:label id="lab_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA_terseLabel_en-US" xlink:label="lab_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales Revenue, Services, Net</link:label>
    <link:label id="lab_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA_label_en-US" xlink:label="lab_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales Revenue, Services, Net [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SalesRevenueServicesNetMember" xlink:label="loc_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA" xlink:to="lab_us-gaap_SalesRevenueServicesNetMember_30EDACEFC7FA5711FAEEE2AC19666AFA" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts Receivable</link:label>
    <link:label id="lab_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B_label_en-US" xlink:label="lab_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivable [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsReceivableMember" xlink:label="loc_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B" xlink:to="lab_us-gaap_AccountsReceivableMember_B16F9371AE1E43E2E34AE2AC1966019B" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D" xlink:to="lab_us-gaap_ConcentrationRiskByTypeAxis_1DE89C3FE285D185E819E2AC1966A83D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85" xlink:to="lab_us-gaap_ConcentrationRiskTypeDomain_7EEBEADE7B0D89932FD3E2AC1967BA85" xlink:type="arc" />
    <link:label id="lab_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8_terseLabel_en-US" xlink:label="lab_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Supplier Concentration Risk</link:label>
    <link:label id="lab_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8_label_en-US" xlink:label="lab_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Supplier Concentration Risk [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SupplierConcentrationRiskMember" xlink:label="loc_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8" xlink:to="lab_us-gaap_SupplierConcentrationRiskMember_8C7E8BA42373B2A57EDDE2AC1967FEE8" xlink:type="arc" />
    <link:label id="lab_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF_terseLabel_en-US" xlink:label="lab_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Customer Concentration Risk</link:label>
    <link:label id="lab_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF_label_en-US" xlink:label="lab_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Customer Concentration Risk [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF" xlink:to="lab_us-gaap_CustomerConcentrationRiskMember_9AEC3360D301A5054E49E2AC1967F7EF" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration Risk [Line Items]</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="loc_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF" xlink:to="lab_us-gaap_ConcentrationRiskLineItems_61B3D656A1CF6B4D7227E2AC196743FF" xlink:type="arc" />
    <link:label id="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1_terseLabel_en-US" xlink:label="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of financial institutions (financial institution)</link:label>
    <link:label id="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1_label_en-US" xlink:label="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Financial Institutions</link:label>
    <link:label id="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1_documentation_en-US" xlink:label="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of Financial Institutions</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_NumberofFinancialInstitutions" xlink:label="loc_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1" xlink:to="lab_oesx_NumberofFinancialInstitutions_128ECC0E833EC56B9FFFE2AC196738C1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32_terseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration risk, percentage</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk, Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32" xlink:to="lab_us-gaap_ConcentrationRiskPercentage1_84BD53E871AD3F87155DE2AC1967FF32" xlink:type="arc" />
    <link:label id="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE_terseLabel_en-US" xlink:label="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration risk, number of entities involved in risk calculation</link:label>
    <link:label id="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE_label_en-US" xlink:label="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk, Number of Entities Involved in Risk Calculation</link:label>
    <link:label id="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE_documentation_en-US" xlink:label="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Concentration Risk, Number of Entities Involved in Risk Calculation</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation" xlink:label="loc_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE" xlink:to="lab_oesx_ConcentrationRiskNumberOfEntitiesInvolvedInRiskCalculation_4B6E52F82FABC1C350ADE2AC1967C2BE" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_D2C644FD42CD432F8A6C3CC8421FAE90_verboseLabel_en-US" xlink:label="lab_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_C5F46C996A275D68BF99C80DEE4C3BB1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Inventories</link:label>
    <link:label id="lab_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_D2C644FD42CD432F8A6C3CC8421FAE90_label_en-US" xlink:label="lab_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_C5F46C996A275D68BF99C80DEE4C3BB1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Net, Items Net of Reserve Alternative [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract" xlink:label="loc_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_C5F46C996A275D68BF99C80DEE4C3BB1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_C5F46C996A275D68BF99C80DEE4C3BB1" xlink:to="lab_us-gaap_InventoryNetItemsNetOfReserveAlternativeAbstract_C5F46C996A275D68BF99C80DEE4C3BB1" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryRawMaterialsAndSupplies_270EC5515EE929B731B53D35E3307E5D_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryRawMaterialsAndSupplies_DA80EE54361C54A490E0158C8D487818" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Raw material and components, cost</link:label>
    <link:label id="lab_us-gaap_InventoryRawMaterialsAndSupplies_270EC5515EE929B731B53D35E3307E5D_label_en-US" xlink:label="lab_us-gaap_InventoryRawMaterialsAndSupplies_DA80EE54361C54A490E0158C8D487818" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Raw Materials and Supplies, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryRawMaterialsAndSupplies" xlink:label="loc_us-gaap_InventoryRawMaterialsAndSupplies_DA80EE54361C54A490E0158C8D487818" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryRawMaterialsAndSupplies_DA80EE54361C54A490E0158C8D487818" xlink:to="lab_us-gaap_InventoryRawMaterialsAndSupplies_DA80EE54361C54A490E0158C8D487818" xlink:type="arc" />
    <link:label id="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_2ADBDEB29611E0AEE92F3D35E58D5DF2_negatedTerseLabel_en-US" xlink:label="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_ACA3F55A122754B68725B7214D40C8B3" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Raw material and components, obsolescence reserve</link:label>
    <link:label id="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_2ADBDEB29611E0AEE92F3D35E58D5DF2_label_en-US" xlink:label="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_ACA3F55A122754B68725B7214D40C8B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Raw Materials and Supplies, Valuation Reserves</link:label>
    <link:label id="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_2ADBDEB29611E0AEE92F3D35E58D5DF2_documentation_en-US" xlink:label="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_ACA3F55A122754B68725B7214D40C8B3" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inventory, Raw Materials and Supplies, Valuation Reserves</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_InventoryRawMaterialsandSuppliesValuationReserves" xlink:label="loc_oesx_InventoryRawMaterialsandSuppliesValuationReserves_ACA3F55A122754B68725B7214D40C8B3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_InventoryRawMaterialsandSuppliesValuationReserves_ACA3F55A122754B68725B7214D40C8B3" xlink:to="lab_oesx_InventoryRawMaterialsandSuppliesValuationReserves_ACA3F55A122754B68725B7214D40C8B3" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_D86AED7C79B17594A3A63D35E8F21F1C_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_5945060789A65686AD90FF2AB521EF36" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Raw material and components, net</link:label>
    <link:label id="lab_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_D86AED7C79B17594A3A63D35E8F21F1C_label_en-US" xlink:label="lab_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_5945060789A65686AD90FF2AB521EF36" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Raw Materials and Supplies, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves" xlink:label="loc_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_5945060789A65686AD90FF2AB521EF36" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_5945060789A65686AD90FF2AB521EF36" xlink:to="lab_us-gaap_InventoryRawMaterialsAndSuppliesNetOfReserves_5945060789A65686AD90FF2AB521EF36" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryWorkInProcess_92AB662216C0565829EE3D35E949167A_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryWorkInProcess_E8763BAA7E145A9BB0DD53D547245077" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Work in process, cost</link:label>
    <link:label id="lab_us-gaap_InventoryWorkInProcess_92AB662216C0565829EE3D35E949167A_label_en-US" xlink:label="lab_us-gaap_InventoryWorkInProcess_E8763BAA7E145A9BB0DD53D547245077" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Work in Process, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryWorkInProcess" xlink:label="loc_us-gaap_InventoryWorkInProcess_E8763BAA7E145A9BB0DD53D547245077" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryWorkInProcess_E8763BAA7E145A9BB0DD53D547245077" xlink:to="lab_us-gaap_InventoryWorkInProcess_E8763BAA7E145A9BB0DD53D547245077" xlink:type="arc" />
    <link:label id="lab_oesx_InventoryWorkinProcessValuationReserves_1335C490AD63552D82983D35EAE64C32_negatedTerseLabel_en-US" xlink:label="lab_oesx_InventoryWorkinProcessValuationReserves_F92E0932C65156A49B03FDF929AB6F81" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Work in process, obsolescence reserve</link:label>
    <link:label id="lab_oesx_InventoryWorkinProcessValuationReserves_1335C490AD63552D82983D35EAE64C32_label_en-US" xlink:label="lab_oesx_InventoryWorkinProcessValuationReserves_F92E0932C65156A49B03FDF929AB6F81" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Work in Process, Valuation Reserves</link:label>
    <link:label id="lab_oesx_InventoryWorkinProcessValuationReserves_1335C490AD63552D82983D35EAE64C32_documentation_en-US" xlink:label="lab_oesx_InventoryWorkinProcessValuationReserves_F92E0932C65156A49B03FDF929AB6F81" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inventory, Work in Process, Valuation Reserves</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_InventoryWorkinProcessValuationReserves" xlink:label="loc_oesx_InventoryWorkinProcessValuationReserves_F92E0932C65156A49B03FDF929AB6F81" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_InventoryWorkinProcessValuationReserves_F92E0932C65156A49B03FDF929AB6F81" xlink:to="lab_oesx_InventoryWorkinProcessValuationReserves_F92E0932C65156A49B03FDF929AB6F81" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryWorkInProcessNetOfReserves_B19F0B69F3205DABDD8E3CC8421FFA07_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryWorkInProcessNetOfReserves_8AE46D708FC954D995EF22BBF81B8DDA" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Work in process, net</link:label>
    <link:label id="lab_us-gaap_InventoryWorkInProcessNetOfReserves_B19F0B69F3205DABDD8E3CC8421FFA07_label_en-US" xlink:label="lab_us-gaap_InventoryWorkInProcessNetOfReserves_8AE46D708FC954D995EF22BBF81B8DDA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Work in Process, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryWorkInProcessNetOfReserves" xlink:label="loc_us-gaap_InventoryWorkInProcessNetOfReserves_8AE46D708FC954D995EF22BBF81B8DDA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryWorkInProcessNetOfReserves_8AE46D708FC954D995EF22BBF81B8DDA" xlink:to="lab_us-gaap_InventoryWorkInProcessNetOfReserves_8AE46D708FC954D995EF22BBF81B8DDA" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryFinishedGoods_C9D9A95A3C74E0488F5B3D35ECCBA3E3_terseLabel_en-US" xlink:label="lab_us-gaap_InventoryFinishedGoods_58547D6B503753239E59616241653221" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finished goods, cost</link:label>
    <link:label id="lab_us-gaap_InventoryFinishedGoods_C9D9A95A3C74E0488F5B3D35ECCBA3E3_label_en-US" xlink:label="lab_us-gaap_InventoryFinishedGoods_58547D6B503753239E59616241653221" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Finished Goods, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryFinishedGoods" xlink:label="loc_us-gaap_InventoryFinishedGoods_58547D6B503753239E59616241653221" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryFinishedGoods_58547D6B503753239E59616241653221" xlink:to="lab_us-gaap_InventoryFinishedGoods_58547D6B503753239E59616241653221" xlink:type="arc" />
    <link:label id="lab_oesx_InventoryFinishedGoodsValuationReserves_312E1F4C7F54BF2AE48A3D35EDBA01F8_negatedTerseLabel_en-US" xlink:label="lab_oesx_InventoryFinishedGoodsValuationReserves_D923FF2A0E795B3686BA0A6A296449AA" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Finished goods, obsolescence reserve</link:label>
    <link:label id="lab_oesx_InventoryFinishedGoodsValuationReserves_312E1F4C7F54BF2AE48A3D35EDBA01F8_label_en-US" xlink:label="lab_oesx_InventoryFinishedGoodsValuationReserves_D923FF2A0E795B3686BA0A6A296449AA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Finished Goods, Valuation Reserves</link:label>
    <link:label id="lab_oesx_InventoryFinishedGoodsValuationReserves_312E1F4C7F54BF2AE48A3D35EDBA01F8_documentation_en-US" xlink:label="lab_oesx_InventoryFinishedGoodsValuationReserves_D923FF2A0E795B3686BA0A6A296449AA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inventory, Finished Goods, Valuation Reserves</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_InventoryFinishedGoodsValuationReserves" xlink:label="loc_oesx_InventoryFinishedGoodsValuationReserves_D923FF2A0E795B3686BA0A6A296449AA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_InventoryFinishedGoodsValuationReserves_D923FF2A0E795B3686BA0A6A296449AA" xlink:to="lab_oesx_InventoryFinishedGoodsValuationReserves_D923FF2A0E795B3686BA0A6A296449AA" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_B4DC605A2A8A6B89711E3CC8421FC615_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_38682407342D5AB3A849F6484B32CC47" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Finished goods, net</link:label>
    <link:label id="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_B4DC605A2A8A6B89711E3CC8421FC615_label_en-US" xlink:label="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_38682407342D5AB3A849F6484B32CC47" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Finished Goods, Net of Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:label="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_38682407342D5AB3A849F6484B32CC47" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryFinishedGoodsNetOfReserves_38682407342D5AB3A849F6484B32CC47" xlink:to="lab_us-gaap_InventoryFinishedGoodsNetOfReserves_38682407342D5AB3A849F6484B32CC47" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryGross_6928321E09D0B5084C3F3D35EF7A5288_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryGross_3E0563A93D035B2DB6922D55A584DA8C" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Cost</link:label>
    <link:label id="lab_us-gaap_InventoryGross_6928321E09D0B5084C3F3D35EF7A5288_label_en-US" xlink:label="lab_us-gaap_InventoryGross_3E0563A93D035B2DB6922D55A584DA8C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryGross" xlink:label="loc_us-gaap_InventoryGross_3E0563A93D035B2DB6922D55A584DA8C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryGross_3E0563A93D035B2DB6922D55A584DA8C" xlink:to="lab_us-gaap_InventoryGross_3E0563A93D035B2DB6922D55A584DA8C" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryValuationReserves_BD3B52B8E203FA4D0E343D35F11018A6_negatedTotalLabel_en-US" xlink:label="lab_us-gaap_InventoryValuationReserves_77F5B5732D8B505AA4BC18ED70808896" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:type="resource" xml:lang="en-US">Obsolescence reserve</link:label>
    <link:label id="lab_us-gaap_InventoryValuationReserves_BD3B52B8E203FA4D0E343D35F11018A6_label_en-US" xlink:label="lab_us-gaap_InventoryValuationReserves_77F5B5732D8B505AA4BC18ED70808896" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory Valuation Reserves</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryValuationReserves" xlink:label="loc_us-gaap_InventoryValuationReserves_77F5B5732D8B505AA4BC18ED70808896" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryValuationReserves_77F5B5732D8B505AA4BC18ED70808896" xlink:to="lab_us-gaap_InventoryValuationReserves_77F5B5732D8B505AA4BC18ED70808896" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryNet_57039B238CDECB33DDA73CC8421F33EC_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryNet_17EF5A324F6B58ED9D516A16450CB391" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net</link:label>
    <link:label id="lab_us-gaap_InventoryNet_57039B238CDECB33DDA73CC8421F33EC_label_en-US" xlink:label="lab_us-gaap_InventoryNet_17EF5A324F6B58ED9D516A16450CB391" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_17EF5A324F6B58ED9D516A16450CB391" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryNet_17EF5A324F6B58ED9D516A16450CB391" xlink:to="lab_us-gaap_InventoryNet_17EF5A324F6B58ED9D516A16450CB391" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Purchase Commitment [Table]</link:label>
    <link:label id="lab_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1_label_en-US" xlink:label="lab_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Purchase Commitment [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermPurchaseCommitmentTable" xlink:label="loc_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1" xlink:to="lab_us-gaap_LongTermPurchaseCommitmentTable_4B4E00D86B268BC3F548FC5D33D3B3B1" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Description [Axis]</link:label>
    <link:label id="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Description [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SaleLeasebackTransactionDescriptionAxis" xlink:label="loc_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4" xlink:to="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_8F22DFE88A87DE11BF6AFC5D33D3AAB4" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SaleLeasebackTransactionNameDomain" xlink:label="loc_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580" xlink:to="lab_us-gaap_SaleLeasebackTransactionNameDomain_650E68ABC0DE674D7513FC5D33D3E580" xlink:type="arc" />
    <link:label id="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1_terseLabel_en-US" xlink:label="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Agreement with Tramontina U.S. Cookware, Inc.</link:label>
    <link:label id="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1_label_en-US" xlink:label="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Agreement with Tramontina U.S. Cookware, Inc. [Member]</link:label>
    <link:label id="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1_documentation_en-US" xlink:label="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Agreement with Tramontina U.S. Cookware, Inc. [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AgreementwithTramontinaU.S.CookwareInc.Member" xlink:label="loc_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1" xlink:to="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_8E0BB07AFE9C599440E9FC5D33D30DF1" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Purchase Commitment [Line Items]</link:label>
    <link:label id="lab_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250_label_en-US" xlink:label="lab_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Purchase Commitment [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermPurchaseCommitmentLineItems" xlink:label="loc_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250" xlink:to="lab_us-gaap_LongTermPurchaseCommitmentLineItems_166EB18E79CB520C3708FC5D33D37250" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B_verboseLabel_en-US" xlink:label="lab_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Rent expense under operating leases</link:label>
    <link:label id="lab_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B_label_en-US" xlink:label="lab_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Rent Expense, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingLeasesRentExpenseNet" xlink:label="loc_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B" xlink:to="lab_us-gaap_OperatingLeasesRentExpenseNet_D91D1C9013836BFA29B4FC5D33D3B77B" xlink:type="arc" />
    <link:label id="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0_terseLabel_en-US" xlink:label="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Term of operating lease</link:label>
    <link:label id="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0_label_en-US" xlink:label="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Lessor Leasing Arrangements, Operating Leases, Term of Contract</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract" xlink:label="loc_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0" xlink:to="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesTermOfContract_A31B7CFF84B0435659D5FC5D33D374D0" xlink:type="arc" />
    <link:label id="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570_terseLabel_en-US" xlink:label="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of lease term extensions (extension option)</link:label>
    <link:label id="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570_label_en-US" xlink:label="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Lessor Leasing Arrangements, Operating Leases, Number of Extension Options</link:label>
    <link:label id="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570_documentation_en-US" xlink:label="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Lessor Leasing Arrangements, Operating Leases, Number of Extension Options</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions" xlink:label="loc_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570" xlink:to="lab_oesx_LessorLeasingArrangementsOperatingLeasesNumberofExtensionOptions_764189CF753723B33549FC5D33D37570" xlink:type="arc" />
    <link:label id="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594_terseLabel_en-US" xlink:label="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Renewal term of operating lease</link:label>
    <link:label id="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594_label_en-US" xlink:label="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Lessor Leasing Arrangements, Operating Leases, Renewal Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm" xlink:label="loc_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594" xlink:to="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_A89BA4E569A184FE368AFC5D33D3C594" xlink:type="arc" />
    <link:label id="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048_terseLabel_en-US" xlink:label="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Monthly rental payments receivable</link:label>
    <link:label id="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048_label_en-US" xlink:label="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Monthly Rental Payments Receivable</link:label>
    <link:label id="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048_documentation_en-US" xlink:label="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Operating Leases, Monthly Rental Payments Receivable</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_OperatingLeasesMonthlyRentalPaymentsReceivable" xlink:label="loc_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048" xlink:to="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_4E72E7243FBA8376397CFC5D33D36048" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash purchase price of sale leaseback</link:label>
    <link:label id="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Net Proceeds, Investing Activities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities" xlink:label="loc_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F" xlink:to="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_8F14F1285C89562091B8FC5D33D3006F" xlink:type="arc" />
    <link:label id="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24_terseLabel_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Area of leased building (sqft)</link:label>
    <link:label id="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24_label_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Area of Leased Property</link:label>
    <link:label id="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24_documentation_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Area of Leased Property</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_SaleLeasebackTransactionAreaofLeasedProperty" xlink:label="loc_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24" xlink:to="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_6D8922FE350350773A5AFC5D33D3DE24" xlink:type="arc" />
    <link:label id="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144_terseLabel_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Building lease term</link:label>
    <link:label id="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144_label_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Lease Term</link:label>
    <link:label id="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144_documentation_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Lease Term</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_SaleLeasebackTransactionLeaseTerm" xlink:label="loc_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144" xlink:to="lab_oesx_SaleLeasebackTransactionLeaseTerm_C6ACFEB5ABFFCF2710B1FC5D33D3B144" xlink:type="arc" />
    <link:label id="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982_terseLabel_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Rent expense per square feet</link:label>
    <link:label id="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982_label_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Rent Expense Per Square Foot</link:label>
    <link:label id="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982_documentation_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Rent Expense Per Square Foot</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_SaleLeasebackTransactionRentExpensePerSquareFoot" xlink:label="loc_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982" xlink:to="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_414E9B371043164FEF08FC5D33D3B982" xlink:type="arc" />
    <link:label id="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Monthly rental payment</link:label>
    <link:label id="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Monthly Rental Payments</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SaleLeasebackTransactionMonthlyRentalPayments" xlink:label="loc_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3" xlink:to="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_7471BD1E7425312FA923FC5D33D4D3E3" xlink:type="arc" />
    <link:label id="lab_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of plaintiff's claims dismissed (claim)</link:label>
    <link:label id="lab_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C_label_en-US" xlink:label="lab_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loss Contingency, Claims Dismissed, Number</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LossContingencyClaimsDismissedNumber" xlink:label="loc_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C" xlink:to="lab_us-gaap_LossContingencyClaimsDismissedNumber_1135E4CD2EF275EBC16BFC5D33D40A2C" xlink:type="arc" />
    <link:label id="lab_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Amount of settlement</link:label>
    <link:label id="lab_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2_label_en-US" xlink:label="lab_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Litigation Settlement, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LitigationSettlementAmount" xlink:label="loc_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2" xlink:to="lab_us-gaap_LitigationSettlementAmount_B76EF1CB0355AAEA209DFC5D33D4EEB2" xlink:type="arc" />
    <link:label id="lab_us-gaap_BuildingAndBuildingImprovementsMember_2BA102A063C5FC4C421A4B8153C07CAC_terseLabel_en-US" xlink:label="lab_us-gaap_BuildingAndBuildingImprovementsMember_A22EA8D1A57A5570A2B4BF9E730E3CC7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Buildings and building improvements</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_BuildingAndBuildingImprovementsMember" xlink:label="loc_us-gaap_BuildingAndBuildingImprovementsMember_A22EA8D1A57A5570A2B4BF9E730E3CC7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BuildingAndBuildingImprovementsMember_A22EA8D1A57A5570A2B4BF9E730E3CC7" xlink:to="lab_us-gaap_BuildingAndBuildingImprovementsMember_A22EA8D1A57A5570A2B4BF9E730E3CC7" xlink:type="arc" />
    <link:label id="lab_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_F007FA15B2E30815B6704B8153C08FA5_verboseLabel_en-US" xlink:label="lab_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_24A2F86842375BAD94EBE915DB45FC38" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Leasehold improvements</link:label>
    <link:label id="lab_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_F007FA15B2E30815B6704B8153C08FA5_label_en-US" xlink:label="lab_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_24A2F86842375BAD94EBE915DB45FC38" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Leaseholds and Leasehold Improvements [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LeaseholdsAndLeaseholdImprovementsMember" xlink:label="loc_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_24A2F86842375BAD94EBE915DB45FC38" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_24A2F86842375BAD94EBE915DB45FC38" xlink:to="lab_us-gaap_LeaseholdsAndLeaseholdImprovementsMember_24A2F86842375BAD94EBE915DB45FC38" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquipmentLeasedToOtherPartyMember_A06075759A40AB4DCA924B8153C09059_terseLabel_en-US" xlink:label="lab_us-gaap_EquipmentLeasedToOtherPartyMember_7085F26EC90D5BD695CF2AB26F40E748" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equipment leased to customers under Power Purchase Agreements</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EquipmentLeasedToOtherPartyMember" xlink:label="loc_us-gaap_EquipmentLeasedToOtherPartyMember_7085F26EC90D5BD695CF2AB26F40E748" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquipmentLeasedToOtherPartyMember_7085F26EC90D5BD695CF2AB26F40E748" xlink:to="lab_us-gaap_EquipmentLeasedToOtherPartyMember_7085F26EC90D5BD695CF2AB26F40E748" xlink:type="arc" />
    <link:label id="lab_us-gaap_EquipmentMember_39A79D6035FB22422C044B8153C027B6_verboseLabel_en-US" xlink:label="lab_us-gaap_EquipmentMember_52B75A1C95FC5AF29FB095DF53A2F677" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Plant equipment</link:label>
    <link:label id="lab_us-gaap_EquipmentMember_39A79D6035FB22422C044B8153C027B6_label_en-US" xlink:label="lab_us-gaap_EquipmentMember_52B75A1C95FC5AF29FB095DF53A2F677" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equipment [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EquipmentMember" xlink:label="loc_us-gaap_EquipmentMember_52B75A1C95FC5AF29FB095DF53A2F677" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquipmentMember_52B75A1C95FC5AF29FB095DF53A2F677" xlink:to="lab_us-gaap_EquipmentMember_52B75A1C95FC5AF29FB095DF53A2F677" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_7B0E2385F5B21A6DE86F4B8153C5A9EA_terseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_941A76827C4C595BAFC7BD87CDCD7349" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Depreciation using the straight-line method</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNetAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNetAbstract_941A76827C4C595BAFC7BD87CDCD7349" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNetAbstract_941A76827C4C595BAFC7BD87CDCD7349" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNetAbstract_941A76827C4C595BAFC7BD87CDCD7349" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_829E9171186D803702564B8153C6FCC5_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_E7D5BA850BE957D7B2C6D9E2826E11CD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Property, plant and equipment, useful life (years)</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_829E9171186D803702564B8153C6FCC5_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_E7D5BA850BE957D7B2C6D9E2826E11CD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Useful Life</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_E7D5BA850BE957D7B2C6D9E2826E11CD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_E7D5BA850BE957D7B2C6D9E2826E11CD" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife_E7D5BA850BE957D7B2C6D9E2826E11CD" xlink:type="arc" />
    <link:label id="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_41FA760B87AEEF1B88C44B8153C61C0D_verboseLabel_en-US" xlink:label="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_2DEA495FF6625B34BA111415EDC2C62C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Property, plant and equipment estimated useful life</link:label>
    <link:label id="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_41FA760B87AEEF1B88C44B8153C61C0D_label_en-US" xlink:label="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_2DEA495FF6625B34BA111415EDC2C62C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property Plant And Equipment Estimated Useful Life</link:label>
    <link:label id="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_41FA760B87AEEF1B88C44B8153C61C0D_documentation_en-US" xlink:label="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_2DEA495FF6625B34BA111415EDC2C62C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Property plant and equipment estimated useful life.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_PropertyPlantAndEquipmentEstimatedUsefulLife" xlink:label="loc_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_2DEA495FF6625B34BA111415EDC2C62C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_2DEA495FF6625B34BA111415EDC2C62C" xlink:to="lab_oesx_PropertyPlantAndEquipmentEstimatedUsefulLife_2DEA495FF6625B34BA111415EDC2C62C" xlink:type="arc" />
    <link:label id="lab_oesx_DocumentAndEntityInformationAbstract_37AA21F5BFA6EE977E86A6C1439B5D43_label_en-US" xlink:label="lab_oesx_DocumentAndEntityInformationAbstract_4B0645D433FC53B19F3AF424391C2A19" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document and Entity Information [Abstract]</link:label>
    <link:label id="lab_oesx_DocumentAndEntityInformationAbstract_37AA21F5BFA6EE977E86A6C1439B5D43_documentation_en-US" xlink:label="lab_oesx_DocumentAndEntityInformationAbstract_4B0645D433FC53B19F3AF424391C2A19" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Document and entity information.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_DocumentAndEntityInformationAbstract" xlink:label="loc_oesx_DocumentAndEntityInformationAbstract_4B0645D433FC53B19F3AF424391C2A19" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_DocumentAndEntityInformationAbstract_4B0645D433FC53B19F3AF424391C2A19" xlink:to="lab_oesx_DocumentAndEntityInformationAbstract_4B0645D433FC53B19F3AF424391C2A19" xlink:type="arc" />
    <link:label id="lab_dei_EntityRegistrantName_26093667029DDE826A73A6C1439B3402_verboseLabel_en-US" xlink:label="lab_dei_EntityRegistrantName_E34B20AEAE035FD9B39753535C0FAE1E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:label id="lab_dei_EntityRegistrantName_26093667029DDE826A73A6C1439B3402_label_en-US" xlink:label="lab_dei_EntityRegistrantName_E34B20AEAE035FD9B39753535C0FAE1E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Registrant Name</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName_E34B20AEAE035FD9B39753535C0FAE1E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityRegistrantName_E34B20AEAE035FD9B39753535C0FAE1E" xlink:to="lab_dei_EntityRegistrantName_E34B20AEAE035FD9B39753535C0FAE1E" xlink:type="arc" />
    <link:label id="lab_dei_EntityCentralIndexKey_8EE61B1DAB973D482254A6C1439B2B0F_verboseLabel_en-US" xlink:label="lab_dei_EntityCentralIndexKey_C2CA6EC6B00053999686946324F522A8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:label id="lab_dei_EntityCentralIndexKey_8EE61B1DAB973D482254A6C1439B2B0F_label_en-US" xlink:label="lab_dei_EntityCentralIndexKey_C2CA6EC6B00053999686946324F522A8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Central Index Key</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey_C2CA6EC6B00053999686946324F522A8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCentralIndexKey_C2CA6EC6B00053999686946324F522A8" xlink:to="lab_dei_EntityCentralIndexKey_C2CA6EC6B00053999686946324F522A8" xlink:type="arc" />
    <link:label id="lab_dei_DocumentType_EC02713FA88B903DA4BFA6C1439B73B8_verboseLabel_en-US" xlink:label="lab_dei_DocumentType_0B0776492F8A5E57ACA653418176CAED" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:label id="lab_dei_DocumentType_EC02713FA88B903DA4BFA6C1439B73B8_label_en-US" xlink:label="lab_dei_DocumentType_0B0776492F8A5E57ACA653418176CAED" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Type</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType_0B0776492F8A5E57ACA653418176CAED" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentType_0B0776492F8A5E57ACA653418176CAED" xlink:to="lab_dei_DocumentType_0B0776492F8A5E57ACA653418176CAED" xlink:type="arc" />
    <link:label id="lab_dei_DocumentPeriodEndDate_90267B3048F1CD1CFF53A6C1439CC41A_verboseLabel_en-US" xlink:label="lab_dei_DocumentPeriodEndDate_FAB40CD59E7E53678ED5CE15E662DEB2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Document Period End Date</link:label>
    <link:label id="lab_dei_DocumentPeriodEndDate_90267B3048F1CD1CFF53A6C1439CC41A_label_en-US" xlink:label="lab_dei_DocumentPeriodEndDate_FAB40CD59E7E53678ED5CE15E662DEB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Period End Date</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="loc_dei_DocumentPeriodEndDate_FAB40CD59E7E53678ED5CE15E662DEB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentPeriodEndDate_FAB40CD59E7E53678ED5CE15E662DEB2" xlink:to="lab_dei_DocumentPeriodEndDate_FAB40CD59E7E53678ED5CE15E662DEB2" xlink:type="arc" />
    <link:label id="lab_dei_AmendmentFlag_FCBEB2DE4E6F6EDDDDC8A6C1439C57F9_verboseLabel_en-US" xlink:label="lab_dei_AmendmentFlag_1C292C8D65CD535BA1CC46FD7FF74309" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:label id="lab_dei_AmendmentFlag_FCBEB2DE4E6F6EDDDDC8A6C1439C57F9_label_en-US" xlink:label="lab_dei_AmendmentFlag_1C292C8D65CD535BA1CC46FD7FF74309" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amendment Flag</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag_1C292C8D65CD535BA1CC46FD7FF74309" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AmendmentFlag_1C292C8D65CD535BA1CC46FD7FF74309" xlink:to="lab_dei_AmendmentFlag_1C292C8D65CD535BA1CC46FD7FF74309" xlink:type="arc" />
    <link:label id="lab_dei_DocumentFiscalYearFocus_714B310129375E7AC481A6C1439C1725_verboseLabel_en-US" xlink:label="lab_dei_DocumentFiscalYearFocus_0DDB16693A4B525B89CAD8FABF00BD08" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Document Fiscal Year Focus</link:label>
    <link:label id="lab_dei_DocumentFiscalYearFocus_714B310129375E7AC481A6C1439C1725_label_en-US" xlink:label="lab_dei_DocumentFiscalYearFocus_0DDB16693A4B525B89CAD8FABF00BD08" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Fiscal Year Focus</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalYearFocus" xlink:label="loc_dei_DocumentFiscalYearFocus_0DDB16693A4B525B89CAD8FABF00BD08" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFiscalYearFocus_0DDB16693A4B525B89CAD8FABF00BD08" xlink:to="lab_dei_DocumentFiscalYearFocus_0DDB16693A4B525B89CAD8FABF00BD08" xlink:type="arc" />
    <link:label id="lab_dei_DocumentFiscalPeriodFocus_E108674E4EECC9276F08A6C1439C06F0_verboseLabel_en-US" xlink:label="lab_dei_DocumentFiscalPeriodFocus_250A272416B15B99ADAC367834087386" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Document Fiscal Period Focus</link:label>
    <link:label id="lab_dei_DocumentFiscalPeriodFocus_E108674E4EECC9276F08A6C1439C06F0_label_en-US" xlink:label="lab_dei_DocumentFiscalPeriodFocus_250A272416B15B99ADAC367834087386" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Document Fiscal Period Focus</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="loc_dei_DocumentFiscalPeriodFocus_250A272416B15B99ADAC367834087386" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentFiscalPeriodFocus_250A272416B15B99ADAC367834087386" xlink:to="lab_dei_DocumentFiscalPeriodFocus_250A272416B15B99ADAC367834087386" xlink:type="arc" />
    <link:label id="lab_dei_CurrentFiscalYearEndDate_1BB55D1A55008D211D93A6C1439C4F9C_verboseLabel_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate_7493AAA3CABB5F73B7EB79B342AC1AC5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:label id="lab_dei_CurrentFiscalYearEndDate_1BB55D1A55008D211D93A6C1439C4F9C_label_en-US" xlink:label="lab_dei_CurrentFiscalYearEndDate_7493AAA3CABB5F73B7EB79B342AC1AC5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Fiscal Year End Date</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="loc_dei_CurrentFiscalYearEndDate_7493AAA3CABB5F73B7EB79B342AC1AC5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CurrentFiscalYearEndDate_7493AAA3CABB5F73B7EB79B342AC1AC5" xlink:to="lab_dei_CurrentFiscalYearEndDate_7493AAA3CABB5F73B7EB79B342AC1AC5" xlink:type="arc" />
    <link:label id="lab_dei_EntityFilerCategory_5DDF686A0439C56C59A1A6C1439CD39F_verboseLabel_en-US" xlink:label="lab_dei_EntityFilerCategory_7732AEC251E953B184132180812EF315" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Entity Filer Category</link:label>
    <link:label id="lab_dei_EntityFilerCategory_5DDF686A0439C56C59A1A6C1439CD39F_label_en-US" xlink:label="lab_dei_EntityFilerCategory_7732AEC251E953B184132180812EF315" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Filer Category</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory_7732AEC251E953B184132180812EF315" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityFilerCategory_7732AEC251E953B184132180812EF315" xlink:to="lab_dei_EntityFilerCategory_7732AEC251E953B184132180812EF315" xlink:type="arc" />
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_985419DBE3DA9E703EA5A6C1439C6D3E_verboseLabel_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding_971BB69D93935329A189B94EF89BBC21" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:label id="lab_dei_EntityCommonStockSharesOutstanding_985419DBE3DA9E703EA5A6C1439C6D3E_label_en-US" xlink:label="lab_dei_EntityCommonStockSharesOutstanding_971BB69D93935329A189B94EF89BBC21" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="loc_dei_EntityCommonStockSharesOutstanding_971BB69D93935329A189B94EF89BBC21" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCommonStockSharesOutstanding_971BB69D93935329A189B94EF89BBC21" xlink:to="lab_dei_EntityCommonStockSharesOutstanding_971BB69D93935329A189B94EF89BBC21" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxDisclosureAbstract_6F083AA91378950FFF7EE7AF7EBE8655_label_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureAbstract_6F083AA91378950FFF7EE7AF7EBE8655" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract_6F083AA91378950FFF7EE7AF7EBE8655" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract_6F083AA91378950FFF7EE7AF7EBE8655" xlink:to="lab_us-gaap_IncomeTaxDisclosureAbstract_6F083AA91378950FFF7EE7AF7EBE8655" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards [Table]</link:label>
    <link:label id="lab_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1_label_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingLossCarryforwardsTable" xlink:label="loc_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1" xlink:to="lab_us-gaap_OperatingLossCarryforwardsTable_8C442BC9543B5E80A6FFE7AF7EC008D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Axis]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3_label_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeTaxAuthorityAxis" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3" xlink:to="lab_us-gaap_IncomeTaxAuthorityAxis_DAC12D3D6C5C579950F0E7AF7EC11DF3" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4_terseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Domain]</link:label>
    <link:label id="lab_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4_label_en-US" xlink:label="lab_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Authority [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4" xlink:to="lab_us-gaap_IncomeTaxAuthorityDomain_18BD53918DF1B5385E7AE7AF7EC194C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D_verboseLabel_en-US" xlink:label="lab_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Federal</link:label>
    <link:label id="lab_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D_label_en-US" xlink:label="lab_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Domestic Tax Authority [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DomesticCountryMember" xlink:label="loc_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D" xlink:to="lab_us-gaap_DomesticCountryMember_E9767D73EEE9860DD7F1E7AF7EC1E83D" xlink:type="arc" />
    <link:label id="lab_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD_verboseLabel_en-US" xlink:label="lab_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">State</link:label>
    <link:label id="lab_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD_label_en-US" xlink:label="lab_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">State and Local Jurisdiction [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StateAndLocalJurisdictionMember" xlink:label="loc_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD" xlink:to="lab_us-gaap_StateAndLocalJurisdictionMember_58A2E512F4803F69A823E7AF7EC221BD" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards [Line Items]</link:label>
    <link:label id="lab_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13_label_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingLossCarryforwardsLineItems" xlink:label="loc_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13" xlink:to="lab_us-gaap_OperatingLossCarryforwardsLineItems_78E2FB4D8E1A065A8EECE7AF7EC20F13" xlink:type="arc" />
    <link:label id="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E_verboseLabel_en-US" xlink:label="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Income Taxes (Textual) [Abstract]</link:label>
    <link:label id="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E_label_en-US" xlink:label="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax (Textual) [Abstract]</link:label>
    <link:label id="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E_documentation_en-US" xlink:label="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Income tax textual.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_IncomeTaxTextualAbstract" xlink:label="loc_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E" xlink:to="lab_oesx_IncomeTaxTextualAbstract_12EF97DE3E812446BDB4E7AF7EC25A4E" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79_verboseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Estimated effective income tax rate</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations_76DDDC8415369DDF6141E7AF7EC25B79" xlink:type="arc" />
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6_terseLabel_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase in tax rate</link:label>
    <link:label id="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6_label_en-US" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationOtherReconcilingItemsPercent_10B465DB7F216A44729FE7AF7EC225A6" xlink:type="arc" />
    <link:label id="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25_terseLabel_en-US" xlink:label="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net tax rate</link:label>
    <link:label id="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25_label_en-US" xlink:label="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Net of Discrete Tax Items, Percent</link:label>
    <link:label id="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25_documentation_en-US" xlink:label="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Net of Discrete Tax Items, Percent</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent" xlink:label="loc_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25" xlink:to="lab_oesx_EffectiveIncomeTaxRateReconciliationNetofDiscreteTaxItemsPercent_C88637D71F1680FDA4F5E7AF7EC28A25" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC_verboseLabel_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Operating loss carryforwards</link:label>
    <link:label id="lab_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC_label_en-US" xlink:label="lab_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="loc_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC" xlink:to="lab_us-gaap_OperatingLossCarryforwards_1F526E3795D2958E52DCE7AF7EC320CC" xlink:type="arc" />
    <link:label id="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8_verboseLabel_en-US" xlink:label="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Exercise of NQSOs</link:label>
    <link:label id="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8_label_en-US" xlink:label="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Loss Carryforwards Associated with Exercise of Non Qualified Stock Options</link:label>
    <link:label id="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8_documentation_en-US" xlink:label="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Exercise of non qualified stock options.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions" xlink:label="loc_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8" xlink:to="lab_oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions_A172E6C30ABDC0EDF6A6E7AF7EC3A4F8" xlink:type="arc" />
    <link:label id="lab_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB_verboseLabel_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Tax credit carryforwards</link:label>
    <link:label id="lab_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB_label_en-US" xlink:label="lab_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Tax Credit Carryforward, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_TaxCreditCarryforwardAmount" xlink:label="loc_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB" xlink:to="lab_us-gaap_TaxCreditCarryforwardAmount_CB90B2CFB94671A58DD9E7AF7EC3CDEB" xlink:type="arc" />
    <link:label id="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B_verboseLabel_en-US" xlink:label="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Valuation allowance</link:label>
    <link:label id="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B_label_en-US" xlink:label="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B" xlink:to="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount_82D04D2C7AF7C7B14219E7AF7EC3854B" xlink:type="arc" />
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2_verboseLabel_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized tax benefits</link:label>
    <link:label id="lab_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2_label_en-US" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2" xlink:to="lab_us-gaap_UnrecognizedTaxBenefits_8E29264748FCBC914833E7AF7EC3E0C2" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_AC1C2F83C1B5A283A76C3CC842003525_terseLabel_en-US" xlink:label="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_FBF1398703D95759900B8D323803400F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets Held under Capital Leases</link:label>
    <link:label id="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_AC1C2F83C1B5A283A76C3CC842003525_label_en-US" xlink:label="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_FBF1398703D95759900B8D323803400F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets Held under Capital Leases [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AssetsHeldUnderCapitalLeasesMember" xlink:label="loc_us-gaap_AssetsHeldUnderCapitalLeasesMember_FBF1398703D95759900B8D323803400F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsHeldUnderCapitalLeasesMember_FBF1398703D95759900B8D323803400F" xlink:to="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_FBF1398703D95759900B8D323803400F" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableGrossCurrent_0DE2050E2E477987310246AFDD088DED_terseLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableGrossCurrent_867C27727A8D516D9BA2DD9BDCD13CFB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable, gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsReceivableGrossCurrent" xlink:label="loc_us-gaap_AccountsReceivableGrossCurrent_867C27727A8D516D9BA2DD9BDCD13CFB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableGrossCurrent_867C27727A8D516D9BA2DD9BDCD13CFB" xlink:to="lab_us-gaap_AccountsReceivableGrossCurrent_867C27727A8D516D9BA2DD9BDCD13CFB" xlink:type="arc" />
    <link:label id="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_6879847D84927E39B49A46AFDD09930E_negatedLabel_en-US" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_1FD477E6163155EB97CC7159A839F223" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Allowance for doubtful accounts</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_1FD477E6163155EB97CC7159A839F223" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_1FD477E6163155EB97CC7159A839F223" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent_1FD477E6163155EB97CC7159A839F223" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventsAbstract_D7EC39711166DE6DDB4FA6C1411155A7_label_en-US" xlink:label="lab_us-gaap_SubsequentEventsAbstract_C84EC57C7B665CE4805D69A1064FCFF8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract_C84EC57C7B665CE4805D69A1064FCFF8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsAbstract_C84EC57C7B665CE4805D69A1064FCFF8" xlink:to="lab_us-gaap_SubsequentEventsAbstract_C84EC57C7B665CE4805D69A1064FCFF8" xlink:type="arc" />
    <link:label id="lab_us-gaap_SubsequentEventsTextBlock_14A200D8D702B2C5947DA6C141112DF5_terseLabel_en-US" xlink:label="lab_us-gaap_SubsequentEventsTextBlock_5E87E9D229ED5723B62BB7A9D6CB77DE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">SUBSEQUENT EVENTS</link:label>
    <link:label id="lab_us-gaap_SubsequentEventsTextBlock_14A200D8D702B2C5947DA6C141112DF5_label_en-US" xlink:label="lab_us-gaap_SubsequentEventsTextBlock_5E87E9D229ED5723B62BB7A9D6CB77DE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock_5E87E9D229ED5723B62BB7A9D6CB77DE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsTextBlock_5E87E9D229ED5723B62BB7A9D6CB77DE" xlink:to="lab_us-gaap_SubsequentEventsTextBlock_5E87E9D229ED5723B62BB7A9D6CB77DE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE" xlink:to="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_C736ED720A145CFEC109D840B563D2FE" xlink:type="arc" />
    <link:label id="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C_terseLabel_en-US" xlink:label="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Orion U.S. Markets</link:label>
    <link:label id="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C_label_en-US" xlink:label="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Energy Management [Member]</link:label>
    <link:label id="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C_documentation_en-US" xlink:label="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Energy Management Member.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EnergyManagementMember" xlink:label="loc_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C" xlink:to="lab_oesx_EnergyManagementMember_F2AC2992851E83B8319BD840B564717C" xlink:type="arc" />
    <link:label id="lab_oesx_EngineeredSystemsMember_CF5A913EBA1819D0E4EDD840B5643AF3_verboseLabel_en-US" xlink:label="lab_oesx_EngineeredSystemsMember_CF5A913EBA1819D0E4EDD840B5643AF3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Orion Engineered Systems</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EngineeredSystemsMember" xlink:label="loc_oesx_EngineeredSystemsMember_CF5A913EBA1819D0E4EDD840B5643AF3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EngineeredSystemsMember_CF5A913EBA1819D0E4EDD840B5643AF3" xlink:to="lab_oesx_EngineeredSystemsMember_CF5A913EBA1819D0E4EDD840B5643AF3" xlink:type="arc" />
    <link:label id="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78_verboseLabel_en-US" xlink:label="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Orion Distribution Services</link:label>
    <link:label id="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78_label_en-US" xlink:label="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Distribution Services [Member]</link:label>
    <link:label id="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78_documentation_en-US" xlink:label="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Distribution Services [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_DistributionServicesMember" xlink:label="loc_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78" xlink:to="lab_oesx_DistributionServicesMember_2C27F051C98BCBB9A390D840B564BA78" xlink:type="arc" />
    <link:label id="lab_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4_terseLabel_en-US" xlink:label="lab_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Corporate and Other</link:label>
    <link:label id="lab_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4_label_en-US" xlink:label="lab_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Corporate and Other [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CorporateAndOtherMember" xlink:label="loc_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4" xlink:to="lab_us-gaap_CorporateAndOtherMember_E1A228048C1CA87107C5D840B56403B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3_terseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Segment Reporting Information [Line Items]</link:label>
    <link:label id="lab_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3_label_en-US" xlink:label="lab_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Information [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3" xlink:to="lab_us-gaap_SegmentReportingInformationLineItems_E78525D456C9D5036973D840B56422C3" xlink:type="arc" />
    <link:label id="lab_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995_verboseLabel_en-US" xlink:label="lab_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Corporate and Other</link:label>
    <link:label id="lab_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995_label_en-US" xlink:label="lab_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Segment Reporting Information, Revenue for Reportable Segment [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SegmentReportingInformationRevenueAbstract" xlink:label="loc_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995" xlink:to="lab_us-gaap_SegmentReportingInformationRevenueAbstract_A5AC2C589AC9D98E8128D840B5645995" xlink:type="arc" />
    <link:label id="lab_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03_verboseLabel_en-US" xlink:label="lab_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Revenues</link:label>
    <link:label id="lab_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03_label_en-US" xlink:label="lab_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenues</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03" xlink:to="lab_us-gaap_Revenues_036C95BBDAAE7B0265DED840B564AA03" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709_terseLabel_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Operating Income (Loss)</link:label>
    <link:label id="lab_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709_label_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Income (Loss)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709" xlink:to="lab_us-gaap_OperatingIncomeLoss_A0B2E1357836E80B7A65D840B564E709" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementOfFinancialPositionAbstract_35CE2FF686971ADDE7E82689A0EA9A31_label_en-US" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract_35CE2FF686971ADDE7E82689A0EA9A31" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Financial Position [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract_35CE2FF686971ADDE7E82689A0EA9A31" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract_35CE2FF686971ADDE7E82689A0EA9A31" xlink:to="lab_us-gaap_StatementOfFinancialPositionAbstract_35CE2FF686971ADDE7E82689A0EA9A31" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61_verboseLabel_en-US" xlink:label="lab_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:label id="lab_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61_label_en-US" xlink:label="lab_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61" xlink:to="lab_us-gaap_AssetsAbstract_0CC6E387072A24E9D9852689A0EA0F61" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_DADE603B3E69B54A2ECC2689A0EA19F3_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_DADE603B3E69B54A2ECC2689A0EA19F3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash and cash equivalents</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_DADE603B3E69B54A2ECC2689A0EA19F3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue_DADE603B3E69B54A2ECC2689A0EA19F3" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue_DADE603B3E69B54A2ECC2689A0EA19F3" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableNetCurrent_106963C7DC6AC6772E7B2689A0EA8B93_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent_106963C7DC6AC6772E7B2689A0EA8B93" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent_106963C7DC6AC6772E7B2689A0EA8B93" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableNetCurrent_106963C7DC6AC6772E7B2689A0EA8B93" xlink:to="lab_us-gaap_AccountsReceivableNetCurrent_106963C7DC6AC6772E7B2689A0EA8B93" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryNet_B0085B07ED14BD930E9A2689A0EA420C_verboseLabel_en-US" xlink:label="lab_us-gaap_InventoryNet_B0085B07ED14BD930E9A2689A0EA420C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Inventories, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet_B0085B07ED14BD930E9A2689A0EA420C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryNet_B0085B07ED14BD930E9A2689A0EA420C" xlink:to="lab_us-gaap_InventoryNet_B0085B07ED14BD930E9A2689A0EA420C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred contract costs</link:label>
    <link:label id="lab_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551_label_en-US" xlink:label="lab_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Costs, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredCostsCurrent" xlink:label="loc_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551" xlink:to="lab_us-gaap_DeferredCostsCurrent_BE2554396012BF75315F2689A0EA3551" xlink:type="arc" />
    <link:label id="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_95D809BAC65EAE8DAAC52689A0EA62FF_verboseLabel_en-US" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_95D809BAC65EAE8DAAC52689A0EA62FF" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_95D809BAC65EAE8DAAC52689A0EA62FF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_95D809BAC65EAE8DAAC52689A0EA62FF" xlink:to="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent_95D809BAC65EAE8DAAC52689A0EA62FF" xlink:type="arc" />
    <link:label id="lab_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181_totalLabel_en-US" xlink:label="lab_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total current assets</link:label>
    <link:label id="lab_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181_label_en-US" xlink:label="lab_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181" xlink:to="lab_us-gaap_AssetsCurrent_9469B306EED704B802242689A0EA3181" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentNet_549994D650F4915D6EEC2689A0EB71D7_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet_549994D650F4915D6EEC2689A0EB71D7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Property and equipment, net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet_549994D650F4915D6EEC2689A0EB71D7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet_549994D650F4915D6EEC2689A0EB71D7" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet_549994D650F4915D6EEC2689A0EB71D7" xlink:type="arc" />
    <link:label id="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5_verboseLabel_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other intangible assets, net</link:label>
    <link:label id="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5_label_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Intangible Assets, Net (Excluding Goodwill)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5" xlink:to="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_13BA8C8702880F84429C2689A0EB93F5" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Long-term accounts receivable</link:label>
    <link:label id="lab_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3_label_en-US" xlink:label="lab_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivable, Net, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsReceivableNetNoncurrent" xlink:label="loc_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3" xlink:to="lab_us-gaap_AccountsReceivableNetNoncurrent_89C6AE3DF3882047D2F22689A0EB6EE3" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other long-term assets</link:label>
    <link:label id="lab_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE_label_en-US" xlink:label="lab_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Assets, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE" xlink:to="lab_us-gaap_OtherAssetsNoncurrent_7E5B9D1B2A04B43888832689A0EB6BBE" xlink:type="arc" />
    <link:label id="lab_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235_totalLabel_en-US" xlink:label="lab_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total assets</link:label>
    <link:label id="lab_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235_label_en-US" xlink:label="lab_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235" xlink:to="lab_us-gaap_Assets_F20E2D5EB95F848E19CF2689A0EBD235" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0_verboseLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Liabilities and Shareholders&#8217; Equity</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities and Equity [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract_89D0F48B57DB1AB62D172689A0EB8CF0" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84_verboseLabel_en-US" xlink:label="lab_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts payable</link:label>
    <link:label id="lab_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84_label_en-US" xlink:label="lab_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Payable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84" xlink:to="lab_us-gaap_AccountsPayableCurrent_4F7515BD51772836DCAA2689A0EB2D84" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272_verboseLabel_en-US" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued expenses and other</link:label>
    <link:label id="lab_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272_label_en-US" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272" xlink:to="lab_us-gaap_AccruedLiabilitiesCurrent_FE3BDF72E0A641D987972689A0EB1272" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred revenue, current</link:label>
    <link:label id="lab_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B_label_en-US" xlink:label="lab_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Revenue, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="loc_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B" xlink:to="lab_us-gaap_DeferredRevenueCurrent_999AF995B0CC6BA8101F2689A0EB940B" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermDebtCurrent_D593897ACCBF9C12D9BA2689A0EBCAFC_verboseLabel_en-US" xlink:label="lab_us-gaap_LongTermDebtCurrent_D593897ACCBF9C12D9BA2689A0EBCAFC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Current maturities of long-term debt and capital leases</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent_D593897ACCBF9C12D9BA2689A0EBCAFC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtCurrent_D593897ACCBF9C12D9BA2689A0EBCAFC" xlink:to="lab_us-gaap_LongTermDebtCurrent_D593897ACCBF9C12D9BA2689A0EBCAFC" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812_totalLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total current liabilities</link:label>
    <link:label id="lab_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812_label_en-US" xlink:label="lab_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812" xlink:to="lab_us-gaap_LiabilitiesCurrent_BAA97C945D371AC1CC122689A0EB2812" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Revolving credit facility</link:label>
    <link:label id="lab_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30_label_en-US" xlink:label="lab_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Line of Credit, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongTermLineOfCredit" xlink:label="loc_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30" xlink:to="lab_us-gaap_LongTermLineOfCredit_7F16932CE516A623BAA92689A0EB6A30" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC_terseLabel_en-US" xlink:label="lab_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt and capital leases, less current maturities</link:label>
    <link:label id="lab_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC_label_en-US" xlink:label="lab_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Long-term Debt, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherLongTermDebtNoncurrent" xlink:label="loc_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC" xlink:to="lab_us-gaap_OtherLongTermDebtNoncurrent_A708A6B36C89748CBB712689A0EBFEFC" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred revenue, long-term</link:label>
    <link:label id="lab_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985_label_en-US" xlink:label="lab_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Revenue, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredRevenueNoncurrent" xlink:label="loc_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985" xlink:to="lab_us-gaap_DeferredRevenueNoncurrent_16CBE2AAE2937725641A2689A0EB3985" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404_verboseLabel_en-US" xlink:label="lab_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other long-term liabilities</link:label>
    <link:label id="lab_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404_label_en-US" xlink:label="lab_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Liabilities, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404" xlink:to="lab_us-gaap_OtherLiabilitiesNoncurrent_F3E45DDEF8726C87619E2689A0EB7404" xlink:type="arc" />
    <link:label id="lab_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049_totalLabel_en-US" xlink:label="lab_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total liabilities</link:label>
    <link:label id="lab_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049_label_en-US" xlink:label="lab_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049" xlink:to="lab_us-gaap_Liabilities_CCCDF762343402F13CFA2689A0EB3049" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA_verboseLabel_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Commitments and contingencies</link:label>
    <link:label id="lab_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA_label_en-US" xlink:label="lab_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="loc_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA" xlink:to="lab_us-gaap_CommitmentsAndContingencies_A2E9D79CCF5D3F2043F92689A0EBEDDA" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243_verboseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shareholders&#8217; equity:</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Attributable to Parent [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockholdersEquityAbstract" xlink:label="loc_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243" xlink:to="lab_us-gaap_StockholdersEquityAbstract_5FE3995CEE5BF2CF12F02689A0ECE243" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, $0.01 par value: Shares authorized: 30,000,000 at September 30, 2016 and March 31, 2016; no shares issued and outstanding at September 30, 2016 and March 31, 2016</link:label>
    <link:label id="lab_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C_label_en-US" xlink:label="lab_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Value, Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PreferredStockValue" xlink:label="loc_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C" xlink:to="lab_us-gaap_PreferredStockValue_9E8A5AD5966E3D2270982689A0ECAB9C" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, no par value: Shares authorized: 200,000,000 at September 30, 2016 and March 31, 2016; shares issued: 37,641,409 at September 30, 2016 and 37,192,559 at March 31, 2016; shares outstanding: 28,214,852 at September 30, 2016 and 27,767,138 at March 31, 2016</link:label>
    <link:label id="lab_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7_label_en-US" xlink:label="lab_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Value, Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7" xlink:to="lab_us-gaap_CommonStockValue_F6AFB0F19D7F9032F78B2689A0ECEFC7" xlink:type="arc" />
    <link:label id="lab_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2_verboseLabel_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Additional paid-in capital</link:label>
    <link:label id="lab_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2_label_en-US" xlink:label="lab_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Additional Paid in Capital</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2" xlink:to="lab_us-gaap_AdditionalPaidInCapital_89ED47FB7125632E07812689A0EC75E2" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C_negatedLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Treasury stock, common shares: 9,426,557 at September 30, 2016 and 9,425,421 at March 31, 2016</link:label>
    <link:label id="lab_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C_label_en-US" xlink:label="lab_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock, Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_TreasuryStockValue" xlink:label="loc_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C" xlink:to="lab_us-gaap_TreasuryStockValue_30355DF73F607B9140482689A0ECC17C" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14_negatedLabel_en-US" xlink:label="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Shareholder notes receivable</link:label>
    <link:label id="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14_label_en-US" xlink:label="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivable from Shareholders or Affiliates for Issuance of Capital Stock</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock" xlink:label="loc_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14" xlink:to="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_59745C2F679C8BB9825E2689A0ECFC14" xlink:type="arc" />
    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B_verboseLabel_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Retained deficit</link:label>
    <link:label id="lab_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B_label_en-US" xlink:label="lab_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retained Earnings (Accumulated Deficit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RetainedEarningsAccumulatedDeficit" xlink:label="loc_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B" xlink:to="lab_us-gaap_RetainedEarningsAccumulatedDeficit_00E6B4CA40F80957C4122689A0ECD65B" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D_totalLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total shareholders&#8217; equity</link:label>
    <link:label id="lab_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D_label_en-US" xlink:label="lab_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Attributable to Parent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D" xlink:to="lab_us-gaap_StockholdersEquity_817218A99E1E973F702F2689A0ECD76D" xlink:type="arc" />
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF_totalLabel_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total liabilities and shareholders&#8217; equity</link:label>
    <link:label id="lab_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF_label_en-US" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities and Equity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquity_3605CC5A0446E1DC19712689A0EC64CF" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredFinanceCostsNoncurrentNet_E213994876A8F2179FC63D5374F0328B_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredFinanceCostsNoncurrentNet_5230A9C629445361A8377497834F1405" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred financing costs</link:label>
    <link:label id="lab_us-gaap_DeferredFinanceCostsNoncurrentNet_E213994876A8F2179FC63D5374F0328B_label_en-US" xlink:label="lab_us-gaap_DeferredFinanceCostsNoncurrentNet_5230A9C629445361A8377497834F1405" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Issuance Costs, Noncurrent, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredFinanceCostsNoncurrentNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNoncurrentNet_5230A9C629445361A8377497834F1405" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredFinanceCostsNoncurrentNet_5230A9C629445361A8377497834F1405" xlink:to="lab_us-gaap_DeferredFinanceCostsNoncurrentNet_5230A9C629445361A8377497834F1405" xlink:type="arc" />
    <link:label id="lab_us-gaap_SecurityDeposit_CE825A31F43247F4E9FD3D5378FF7C33_terseLabel_en-US" xlink:label="lab_us-gaap_SecurityDeposit_AB209A0977D652EEAA14255F341E1A0C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Security deposits</link:label>
    <link:label id="lab_us-gaap_SecurityDeposit_CE825A31F43247F4E9FD3D5378FF7C33_label_en-US" xlink:label="lab_us-gaap_SecurityDeposit_AB209A0977D652EEAA14255F341E1A0C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Security Deposit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SecurityDeposit" xlink:label="loc_us-gaap_SecurityDeposit_AB209A0977D652EEAA14255F341E1A0C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SecurityDeposit_AB209A0977D652EEAA14255F341E1A0C" xlink:to="lab_us-gaap_SecurityDeposit_AB209A0977D652EEAA14255F341E1A0C" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherAssetsMiscellaneousNoncurrent_AB392149741BE199CEE73D53B18B16DE_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAssetsMiscellaneousNoncurrent_7EAC57AD5E985E949FEE7758CB49F9F5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other</link:label>
    <link:label id="lab_us-gaap_OtherAssetsMiscellaneousNoncurrent_AB392149741BE199CEE73D53B18B16DE_label_en-US" xlink:label="lab_us-gaap_OtherAssetsMiscellaneousNoncurrent_7EAC57AD5E985E949FEE7758CB49F9F5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Assets, Miscellaneous, Noncurrent</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherAssetsMiscellaneousNoncurrent" xlink:label="loc_us-gaap_OtherAssetsMiscellaneousNoncurrent_7EAC57AD5E985E949FEE7758CB49F9F5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssetsMiscellaneousNoncurrent_7EAC57AD5E985E949FEE7758CB49F9F5" xlink:to="lab_us-gaap_OtherAssetsMiscellaneousNoncurrent_7EAC57AD5E985E949FEE7758CB49F9F5" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherAssetsNoncurrent_E895FCB072539EFE30463D53B5BC114A_totalLabel_en-US" xlink:label="lab_us-gaap_OtherAssetsNoncurrent_5164C128AACB50069E274D226A761869" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent_5164C128AACB50069E274D226A761869" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssetsNoncurrent_5164C128AACB50069E274D226A761869" xlink:to="lab_us-gaap_OtherAssetsNoncurrent_5164C128AACB50069E274D226A761869" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxDisclosureTextBlock_584D9ADECF13A8D35B9A46D3FA3F1B5A_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock_4A3818BB76D5548298D7FF1144B7C033" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">INCOME TAXES</link:label>
    <link:label id="lab_us-gaap_IncomeTaxDisclosureTextBlock_584D9ADECF13A8D35B9A46D3FA3F1B5A_label_en-US" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock_4A3818BB76D5548298D7FF1144B7C033" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="loc_us-gaap_IncomeTaxDisclosureTextBlock_4A3818BB76D5548298D7FF1144B7C033" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureTextBlock_4A3818BB76D5548298D7FF1144B7C033" xlink:to="lab_us-gaap_IncomeTaxDisclosureTextBlock_4A3818BB76D5548298D7FF1144B7C033" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_87C22661E537922CC073A6C144599493_verboseLabel_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_756656060417587BA53D4AF15007F967" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SHAREHOLDERS' EQUITY</link:label>
    <link:label id="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_87C22661E537922CC073A6C144599493_label_en-US" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_756656060417587BA53D4AF15007F967" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Note Disclosure [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock_756656060417587BA53D4AF15007F967" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock_756656060417587BA53D4AF15007F967" xlink:to="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock_756656060417587BA53D4AF15007F967" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Line of Credit Facility [Table]</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityTable" xlink:label="loc_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F" xlink:to="lab_us-gaap_LineOfCreditFacilityTable_AE275D74D1BA74CA703220CB322CC10F" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentAxis" xlink:label="loc_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8" xlink:to="lab_us-gaap_DebtInstrumentAxis_A25507981F38D12B797120CB322C74D8" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentNameDomain" xlink:label="loc_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF" xlink:to="lab_us-gaap_DebtInstrumentNameDomain_90DB2BEC2D0952BBCFAC20CB322CE7DF" xlink:type="arc" />
    <link:label id="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502_terseLabel_en-US" xlink:label="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Agreement</link:label>
    <link:label id="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502_label_en-US" xlink:label="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Agreement [Member]</link:label>
    <link:label id="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502_documentation_en-US" xlink:label="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Credit Agreement</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_CreditAgreementMember" xlink:label="loc_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502" xlink:to="lab_oesx_CreditAgreementMember_7CE5546358612AB6F9CE20CB322C5502" xlink:type="arc" />
    <link:label id="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380_terseLabel_en-US" xlink:label="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">December 2014 OTA Finance Program</link:label>
    <link:label id="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380_label_en-US" xlink:label="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">December 2014 OTA Finance Program [Member]</link:label>
    <link:label id="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380_documentation_en-US" xlink:label="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">December 2014 OTA Finance Program [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_December2014OTAFinanceProgramMember" xlink:label="loc_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380" xlink:to="lab_oesx_December2014OTAFinanceProgramMember_84D34AA4F44FD15D07BD20CB322C4380" xlink:type="arc" />
    <link:label id="lab_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6_label_en-US" xlink:label="lab_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6" xlink:to="lab_us-gaap_CreditFacilityAxis_354C6DE1674C13E91A1420CB322CFDC6" xlink:type="arc" />
    <link:label id="lab_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F_terseLabel_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:label id="lab_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F_label_en-US" xlink:label="lab_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Credit Facility [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F" xlink:to="lab_us-gaap_CreditFacilityDomain_1434312D57024C3D44ED20CB322C649F" xlink:type="arc" />
    <link:label id="lab_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5_terseLabel_en-US" xlink:label="lab_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Letter of Credit</link:label>
    <link:label id="lab_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5_label_en-US" xlink:label="lab_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Letter of Credit [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LetterOfCreditMember" xlink:label="loc_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5" xlink:to="lab_us-gaap_LetterOfCreditMember_38197F1E4187091038FC20CB322D88C5" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Lender Name [Axis]</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Lender Name [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityAxis" xlink:label="loc_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282" xlink:to="lab_us-gaap_LineOfCreditFacilityAxis_D5186891D3FF8E60CCAE20CB322D1282" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Lender [Domain]</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Lender [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityLenderDomain" xlink:label="loc_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8" xlink:to="lab_us-gaap_LineOfCreditFacilityLenderDomain_B8E24C79C815B2F418BE20CB322D63F8" xlink:type="arc" />
    <link:label id="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4_terseLabel_en-US" xlink:label="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Wells Fargo Bank, National Association</link:label>
    <link:label id="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4_label_en-US" xlink:label="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Wells Fargo Bank, National Association [Member]</link:label>
    <link:label id="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4_documentation_en-US" xlink:label="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Wells Fargo Bank, National Association [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_WellsFargoBankNationalAssociationMember" xlink:label="loc_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4" xlink:to="lab_oesx_WellsFargoBankNationalAssociationMember_9BDFF6AA1E25F53A153720CB322D52C4" xlink:type="arc" />
    <link:label id="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59_terseLabel_en-US" xlink:label="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">De Lage Landen Financial Services, Inc.</link:label>
    <link:label id="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59_label_en-US" xlink:label="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">De Lage Landen Financial Services, Inc. [Member]</link:label>
    <link:label id="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59_documentation_en-US" xlink:label="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">De Lage Landen Financial Services, Inc. [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_DeLageLandenFinancialServicesInc.Member" xlink:label="loc_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59" xlink:to="lab_oesx_DeLageLandenFinancialServicesInc.Member_C8FC8B0A6247D36283CB20CB322D4C59" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
    <link:label id="lab_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873_label_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873" xlink:to="lab_us-gaap_LongtermDebtTypeAxis_2520A03BD4B75A6570E020CB322D1873" xlink:type="arc" />
    <link:label id="lab_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C_terseLabel_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Domain]</link:label>
    <link:label id="lab_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C_label_en-US" xlink:label="lab_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Type [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C" xlink:to="lab_us-gaap_LongtermDebtTypeDomain_52F5132104A5E0C7C69520CB322D906C" xlink:type="arc" />
    <link:label id="lab_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A_terseLabel_en-US" xlink:label="lab_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Secured Debt</link:label>
    <link:label id="lab_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A_label_en-US" xlink:label="lab_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Secured Debt [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SecuredDebtMember" xlink:label="loc_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A" xlink:to="lab_us-gaap_SecuredDebtMember_4899D70FA838FDE67C9220CB322DEC4A" xlink:type="arc" />
    <link:label id="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA_terseLabel_en-US" xlink:label="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">June 2011 OTA Finance Program</link:label>
    <link:label id="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA_label_en-US" xlink:label="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">June 2011 OTA Finance Program [Member]</link:label>
    <link:label id="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA_documentation_en-US" xlink:label="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">June 2011 OTA Finance Program [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_June2011OtaFinanceProgramMember" xlink:label="loc_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA" xlink:to="lab_oesx_June2011OtaFinanceProgramMember_81FA2DF6E608A4B70EEA20CB322D0FFA" xlink:type="arc" />
    <link:label id="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12_terseLabel_en-US" xlink:label="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Agreement with Wisconsin Department of Commerce</link:label>
    <link:label id="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12_label_en-US" xlink:label="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Agreement with Wisconsin Department of Commerce [Member]</link:label>
    <link:label id="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12_documentation_en-US" xlink:label="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Agreement with Wisconsin Department of Commerce [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AgreementWithWisconsinDepartmentOfCommerceMember" xlink:label="loc_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12" xlink:to="lab_oesx_AgreementWithWisconsinDepartmentOfCommerceMember_FEB6137E6457BCEAFF5B20CB322D8E12" xlink:type="arc" />
    <link:label id="lab_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18_terseLabel_en-US" xlink:label="lab_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Variable Rate [Axis]</link:label>
    <link:label id="lab_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18_label_en-US" xlink:label="lab_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Variable Rate [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18" xlink:to="lab_us-gaap_VariableRateAxis_CFD2F08C4D8ECFF9683C20CB322D8A18" xlink:type="arc" />
    <link:label id="lab_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD_terseLabel_en-US" xlink:label="lab_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Variable Rate [Domain]</link:label>
    <link:label id="lab_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD_label_en-US" xlink:label="lab_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Variable Rate [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD" xlink:to="lab_us-gaap_VariableRateDomain_521A728DB040C09D828A20CB322D8AAD" xlink:type="arc" />
    <link:label id="lab_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4_terseLabel_en-US" xlink:label="lab_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">London Interbank Offered Rate (LIBOR)</link:label>
    <link:label id="lab_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4_label_en-US" xlink:label="lab_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">London Interbank Offered Rate (LIBOR) [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LondonInterbankOfferedRateLIBORMember" xlink:label="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4" xlink:to="lab_us-gaap_LondonInterbankOfferedRateLIBORMember_11234D2A27CB0615958720CB322D97C4" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Line of Credit Facility [Line Items]</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityLineItems" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F" xlink:to="lab_us-gaap_LineOfCreditFacilityLineItems_4D43192988240C45D04320CB322E7C3F" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit facility current limit</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Current Borrowing Capacity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043" xlink:to="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_27DB9A0887550ABB3EF620CB322E0043" xlink:type="arc" />
    <link:label id="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343_terseLabel_en-US" xlink:label="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Potential maximum borrowing</link:label>
    <link:label id="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343_label_en-US" xlink:label="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Potential Maximum Borrowing Capacity</link:label>
    <link:label id="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343_documentation_en-US" xlink:label="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Potential Maximum Borrowing Capacity</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity" xlink:label="loc_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343" xlink:to="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_6DD08A900144606AC89820CDCC61D343" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit facility, maximum limit</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Maximum Borrowing Capacity</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2" xlink:to="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_3CB3F950CF57C30FE31D20CB322E8DB2" xlink:type="arc" />
    <link:label id="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203_terseLabel_en-US" xlink:label="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit facility, minimum indebtedness ratio</link:label>
    <link:label id="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203_label_en-US" xlink:label="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Covenant Terms, Minimum Indebtedness Ratio</link:label>
    <link:label id="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203_documentation_en-US" xlink:label="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Covenant Terms, Minimum Indebtedness Ratio</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio" xlink:label="loc_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203" xlink:to="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_77D7E2B9FA561676BBDF20CB322E2203" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basis spread on variable rate (percent)</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Basis Spread on Variable Rate</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD" xlink:to="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_DB09025886F1B514CF6620CB322E8DDD" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest payment</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Periodic Payment, Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentPeriodicPaymentInterest" xlink:label="loc_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF" xlink:to="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_C0C8B9439ACC0BC39C7520CB322EE6FF" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest rate (percent)</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Interest Rate, Effective Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentInterestRateEffectivePercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9" xlink:to="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_8A985CBB78D135F0AC3220CB322E3DE9" xlink:type="arc" />
    <link:label id="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Unused commitment fee (percent)</link:label>
    <link:label id="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Unused Capacity, Commitment Fee Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501" xlink:to="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_23BC519A9E6961B4EEDB20CB322E6501" xlink:type="arc" />
    <link:label id="lab_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2_terseLabel_en-US" xlink:label="lab_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Letters of credit outstanding</link:label>
    <link:label id="lab_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2_label_en-US" xlink:label="lab_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Letters of Credit Outstanding, Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LettersOfCreditOutstandingAmount" xlink:label="loc_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2" xlink:to="lab_us-gaap_LettersOfCreditOutstandingAmount_99C83A63B09EE8C70C1E20CB322E94C2" xlink:type="arc" />
    <link:label id="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF_terseLabel_en-US" xlink:label="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Credit facility, additional borrowing capacity</link:label>
    <link:label id="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF_label_en-US" xlink:label="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Additional Borrowing Capacity</link:label>
    <link:label id="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF_documentation_en-US" xlink:label="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Line of Credit Facility, Additional Borrowing Capacity</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_LineofCreditFacilityAdditionalBorrowingCapacity" xlink:label="loc_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF" xlink:to="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_34412737EDE11CB94EC420CB322E93FF" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Face amount of debt</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Face Amount</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737" xlink:to="lab_us-gaap_DebtInstrumentFaceAmount_02AAF01F40F3F41A9D8420CB322EF737" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Lease interest rate (percent)</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Interest Rate, Stated Percentage</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23" xlink:to="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage_9594D1431FBB5CB72EC620CB322EBF23" xlink:type="arc" />
    <link:label id="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B_terseLabel_en-US" xlink:label="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of lease agreement (lease agreement)</link:label>
    <link:label id="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B_label_en-US" xlink:label="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Lease Agreements</link:label>
    <link:label id="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B_documentation_en-US" xlink:label="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of Lease Agreements</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_NumberofLeaseAgreements" xlink:label="loc_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B" xlink:to="lab_oesx_NumberofLeaseAgreements_9EF167E2047A48255D5F20CB322E705B" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Lease agreement, principal amount</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Long-term Debt, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2" xlink:to="lab_us-gaap_DebtInstrumentCarryingAmount_CFE082D78384E213FA5420CB322E71B2" xlink:type="arc" />
    <link:label id="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6_terseLabel_en-US" xlink:label="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net equipment lease obligation buyout option</link:label>
    <link:label id="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6_label_en-US" xlink:label="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Buyout Option</link:label>
    <link:label id="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6_documentation_en-US" xlink:label="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt Instrument, Buyout Option</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_DebtInstrumentBuyoutOption" xlink:label="loc_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6" xlink:to="lab_oesx_DebtInstrumentBuyoutOption_11ACA08935B5533912B120CB322E2BE6" xlink:type="arc" />
    <link:label id="lab_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1_terseLabel_en-US" xlink:label="lab_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Principal amount of secured debt</link:label>
    <link:label id="lab_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1_label_en-US" xlink:label="lab_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Secured Debt</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SecuredDebt" xlink:label="loc_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1" xlink:to="lab_us-gaap_SecuredDebt_D1C465FDFD1A7A28243320CB322FC1C1" xlink:type="arc" />
    <link:label id="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0_terseLabel_en-US" xlink:label="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of contracts for collateral (contract)</link:label>
    <link:label id="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0_label_en-US" xlink:label="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Number Of Contracts For Collateral</link:label>
    <link:label id="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0_documentation_en-US" xlink:label="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Debt Instrument, Number of Customer Contracts</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_DebtInstrumentNumberOfContractsForCollateral" xlink:label="loc_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0" xlink:to="lab_oesx_DebtInstrumentNumberOfContractsForCollateral_C0FC0E863E8D35F179AA20CB322F1DC0" xlink:type="arc" />
    <link:label id="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838_terseLabel_en-US" xlink:label="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Period of time without interest accruing or principal payments due</link:label>
    <link:label id="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838_label_en-US" xlink:label="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Period of Time without Interest Accruing or Principal Payments Due</link:label>
    <link:label id="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838_documentation_en-US" xlink:label="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Period of Time without Interest Accruing or Principal Payments Due</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue" xlink:label="loc_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838" xlink:to="lab_oesx_PeriodOfTimeWithoutInterestAccruingOrPrincipalPaymentsDue_5796F1481F916C53C5A020CB322F7838" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Periodic payment</link:label>
    <link:label id="lab_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Instrument, Periodic Payment</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DebtInstrumentPeriodicPayment" xlink:label="loc_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66" xlink:to="lab_us-gaap_DebtInstrumentPeriodicPayment_ADDB7B76375491BEDAC820CB322FBF66" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Stock by Class [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D_label_en-US" xlink:label="lab_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Stock by Class [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D" xlink:to="lab_us-gaap_ScheduleOfStockByClassTable_F9BEEAFB5934EEE62BC7FC7E27367E1D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26_terseLabel_en-US" xlink:label="lab_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Stock [Line Items]</link:label>
    <link:label id="lab_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26_label_en-US" xlink:label="lab_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26" xlink:to="lab_us-gaap_ClassOfStockLineItems_D8812AE6A0865E2A5008FC7E27460E26" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B_verboseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shares Issued Under ESPP Plan (shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, Employee Stock Purchase Plans</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_1E790830E1A71F85AAE3FC5D33CC8A8B" xlink:type="arc" />
    <link:label id="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A_verboseLabel_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Closing Market Price (usd per share)</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A_label_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Stock Purchase Plan Closing Market Price Of Shares Purchased</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A_documentation_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee stock purchase plans weighted averages purchase price of shares purchased.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased" xlink:label="loc_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A" xlink:to="lab_oesx_EmployeeStockPurchasePlanClosingMarketPriceOfSharesPurchased_FB0C3692C5727573EF05FC5D33CC435A" xlink:type="arc" />
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01_verboseLabel_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shares Issued Under Loan Program (shares)</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01_label_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Stock Purchase Plans Debt Structure Shares Issued</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01_documentation_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee stock purchase plans debt structure shares issued.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued" xlink:label="loc_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01" xlink:to="lab_oesx_EmployeeStockPurchasePlansDebtStructureSharesIssued_283C050697C2718CA64CFC5D33CCBA01" xlink:type="arc" />
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D_verboseLabel_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Dollar Value of Loans Issued</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D_label_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Stock Purchase Plans Debt Structure Direct Loan Amount</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D_documentation_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee stock purchase plans debt structure direct loan amount.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount" xlink:label="loc_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D" xlink:to="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanAmount_1BE2FDB6DC201786CB39FC5D33CCDA4D" xlink:type="arc" />
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95_verboseLabel_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Repayment of Loans</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95_label_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Stock Purchase Plans Debt Structure Direct Loan Repayment Amount</link:label>
    <link:label id="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95_documentation_en-US" xlink:label="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Employee stock purchase plans debt structure direct loan repayment amount.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount" xlink:label="loc_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95" xlink:to="lab_oesx_EmployeeStockPurchasePlansDebtStructureDirectLoanRepaymentAmount_230E89AB46EC668BADD1FC5D33CC1D95" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_268723395CF696B591D3FC5D33CCEC95_terseLabel_en-US" xlink:label="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_268723395CF696B591D3FC5D33CCEC95" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loans issued to non-executive employees outstanding</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock" xlink:label="loc_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_268723395CF696B591D3FC5D33CCEC95" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_268723395CF696B591D3FC5D33CCEC95" xlink:to="lab_us-gaap_ReceivableFromShareholdersOrAffiliatesForIssuanceOfCapitalStock_268723395CF696B591D3FC5D33CCEC95" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_5A69B02F62CB90C9FD653CC84277CD15_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_C4CD3350F1815344ADD7C4E0B501D696" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Schedule of accounts receivable</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_5A69B02F62CB90C9FD653CC84277CD15_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_C4CD3350F1815344ADD7C4E0B501D696" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_C4CD3350F1815344ADD7C4E0B501D696" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_C4CD3350F1815344ADD7C4E0B501D696" xlink:to="lab_us-gaap_ScheduleOfAccountsNotesLoansAndFinancingReceivableTextBlock_C4CD3350F1815344ADD7C4E0B501D696" xlink:type="arc" />
    <link:label id="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_FD18CD877AA0CDE0AA6C3CC8427734F0_verboseLabel_en-US" xlink:label="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_3662EB8FB4ED5C70ADFEDCF546AE0556" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Schedule of financing receivables</link:label>
    <link:label id="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_FD18CD877AA0CDE0AA6C3CC8427734F0_label_en-US" xlink:label="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_3662EB8FB4ED5C70ADFEDCF546AE0556" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financing Receivable Credit Quality Indicators [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock" xlink:label="loc_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_3662EB8FB4ED5C70ADFEDCF546AE0556" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_3662EB8FB4ED5C70ADFEDCF546AE0556" xlink:to="lab_us-gaap_FinancingReceivableCreditQualityIndicatorsTableTextBlock_3662EB8FB4ED5C70ADFEDCF546AE0556" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_11D29CCCCEA25E7143453CC84277D62D_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_CA4ED95555CA5574984CE6AEC921F57D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Inventories</link:label>
    <link:label id="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_11D29CCCCEA25E7143453CC84277D62D_label_en-US" xlink:label="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_CA4ED95555CA5574984CE6AEC921F57D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Inventory, Current [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_CA4ED95555CA5574984CE6AEC921F57D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_CA4ED95555CA5574984CE6AEC921F57D" xlink:to="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock_CA4ED95555CA5574984CE6AEC921F57D" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_97DD0AAAC8ED81BC168F3D428D51E6EA_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_EBA4AD6E60AD54BE9CE1C2DD4B336E5D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
    <link:label id="lab_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_97DD0AAAC8ED81BC168F3D428D51E6EA_label_en-US" xlink:label="lab_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_EBA4AD6E60AD54BE9CE1C2DD4B336E5D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock" xlink:label="loc_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_EBA4AD6E60AD54BE9CE1C2DD4B336E5D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_EBA4AD6E60AD54BE9CE1C2DD4B336E5D" xlink:to="lab_us-gaap_DeferredCostsCapitalizedPrepaidAndOtherAssetsDisclosureTextBlock_EBA4AD6E60AD54BE9CE1C2DD4B336E5D" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_016D6F7FCD85839FC5BA3CC842771709_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_C17C286B8B5C50A6812C0B0A51AD03CE" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Property and equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_016D6F7FCD85839FC5BA3CC842771709_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_C17C286B8B5C50A6812C0B0A51AD03CE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_C17C286B8B5C50A6812C0B0A51AD03CE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTextBlock_C17C286B8B5C50A6812C0B0A51AD03CE" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTextBlock_C17C286B8B5C50A6812C0B0A51AD03CE" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_E176F817958A0616C7233CC84277D41E_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_4573C67014D15DA08AE5D179C90A3948" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of equipment under capital leases</link:label>
    <link:label id="lab_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_E176F817958A0616C7233CC84277D41E_label_en-US" xlink:label="lab_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_4573C67014D15DA08AE5D179C90A3948" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Capital Leased Assets [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_4573C67014D15DA08AE5D179C90A3948" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_4573C67014D15DA08AE5D179C90A3948" xlink:to="lab_us-gaap_ScheduleOfCapitalLeasedAsssetsTableTextBlock_4573C67014D15DA08AE5D179C90A3948" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_2F2E1D9E982E4A89AE773CC84277099B_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_A5473F65E98E5D35899F8472E394B5A3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of intangible assets</link:label>
    <link:label id="lab_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_2F2E1D9E982E4A89AE773CC84277099B_label_en-US" xlink:label="lab_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_A5473F65E98E5D35899F8472E394B5A3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Intangible Assets and Goodwill [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_A5473F65E98E5D35899F8472E394B5A3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_A5473F65E98E5D35899F8472E394B5A3" xlink:to="lab_us-gaap_ScheduleOfIntangibleAssetsAndGoodwillTableTextBlock_A5473F65E98E5D35899F8472E394B5A3" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_A8729A9ED42585D4420E3D54ADB7D8D2_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_069C67AE994551A7BB7D4E5517EF21D1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of other long-term assets</link:label>
    <link:label id="lab_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_A8729A9ED42585D4420E3D54ADB7D8D2_label_en-US" xlink:label="lab_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_069C67AE994551A7BB7D4E5517EF21D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Other Assets, Noncurrent [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock" xlink:label="loc_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_069C67AE994551A7BB7D4E5517EF21D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_069C67AE994551A7BB7D4E5517EF21D1" xlink:to="lab_us-gaap_ScheduleOfOtherAssetsNoncurrentTextBlock_069C67AE994551A7BB7D4E5517EF21D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_0EFF74EE9FD594FDB6303D5A85FFC304_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_611F2A0A0D09558C945EC62FFDAED5EA" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of accrued expenses and other</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_0EFF74EE9FD594FDB6303D5A85FFC304_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_611F2A0A0D09558C945EC62FFDAED5EA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Accrued Liabilities [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_611F2A0A0D09558C945EC62FFDAED5EA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_611F2A0A0D09558C945EC62FFDAED5EA" xlink:to="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock_611F2A0A0D09558C945EC62FFDAED5EA" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A8A3482E8772F44430993CC84277D97F_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A2F341DC69ED5DC5BF1B3D732C55BAF1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Changes in warranty accrual</link:label>
    <link:label id="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A8A3482E8772F44430993CC84277D97F_label_en-US" xlink:label="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A2F341DC69ED5DC5BF1B3D732C55BAF1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Product Warranty Liability [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A2F341DC69ED5DC5BF1B3D732C55BAF1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A2F341DC69ED5DC5BF1B3D732C55BAF1" xlink:to="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock_A2F341DC69ED5DC5BF1B3D732C55BAF1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_58EF496B4ED6AFFA2CBA3CC84277E8B7_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_9310CC982CEE56668B66E4393BAAFCD0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Summary of the effect of net income per common share</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_58EF496B4ED6AFFA2CBA3CC84277E8B7_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_9310CC982CEE56668B66E4393BAAFCD0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_9310CC982CEE56668B66E4393BAAFCD0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_9310CC982CEE56668B66E4393BAAFCD0" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_9310CC982CEE56668B66E4393BAAFCD0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_E3219D5519A14B9184043CC84277A411_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_5B7214F4F499566881256BEDE7377E9B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of potentially dilutive securities</link:label>
    <link:label id="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_E3219D5519A14B9184043CC84277A411_label_en-US" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_5B7214F4F499566881256BEDE7377E9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_5B7214F4F499566881256BEDE7377E9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_5B7214F4F499566881256BEDE7377E9B" xlink:to="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock_5B7214F4F499566881256BEDE7377E9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE_terseLabel_en-US" xlink:label="lab_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Plan Name [Axis]</link:label>
    <link:label id="lab_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE_label_en-US" xlink:label="lab_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Plan Name [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE" xlink:to="lab_us-gaap_PlanNameAxis_FFB5264E5E00C4224296272271CE7ABE" xlink:type="arc" />
    <link:label id="lab_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C_terseLabel_en-US" xlink:label="lab_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Plan Name [Domain]</link:label>
    <link:label id="lab_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C_label_en-US" xlink:label="lab_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Plan Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C" xlink:to="lab_us-gaap_PlanNameDomain_C55DF3ED26204F041A48272271CE041C" xlink:type="arc" />
    <link:label id="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE_terseLabel_en-US" xlink:label="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2016 Omnibus Incentive Plan</link:label>
    <link:label id="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE_label_en-US" xlink:label="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">2016 Omnibus Incentive Plan [Member]</link:label>
    <link:label id="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE_documentation_en-US" xlink:label="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">2016 Omnibus Incentive Plan [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_A2016OmnibusIncentivePlanMember" xlink:label="loc_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE" xlink:to="lab_oesx_A2016OmnibusIncentivePlanMember_3A47EF55227983E28281272271CEB0AE" xlink:type="arc" />
    <link:label id="lab_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43_terseLabel_en-US" xlink:label="lab_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Stock [Axis]</link:label>
    <link:label id="lab_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43_label_en-US" xlink:label="lab_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StatementClassOfStockAxis" xlink:label="loc_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43" xlink:to="lab_us-gaap_StatementClassOfStockAxis_D76ED9A3A35CB3B4AFFC272271CF1F43" xlink:type="arc" />
    <link:label id="lab_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A_terseLabel_en-US" xlink:label="lab_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Stock [Domain]</link:label>
    <link:label id="lab_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A_label_en-US" xlink:label="lab_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ClassOfStockDomain" xlink:label="loc_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A" xlink:to="lab_us-gaap_ClassOfStockDomain_D157E4A17FB268896655272271CF298A" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common Stock</link:label>
    <link:label id="lab_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770_label_en-US" xlink:label="lab_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770" xlink:to="lab_us-gaap_CommonStockMember_E0B40FB4F1E1BAA38B62272271CF7770" xlink:type="arc" />
    <link:label id="lab_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635_terseLabel_en-US" xlink:label="lab_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Title of Individual [Axis]</link:label>
    <link:label id="lab_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635_label_en-US" xlink:label="lab_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Title of Individual [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_TitleOfIndividualAxis" xlink:label="loc_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635" xlink:to="lab_us-gaap_TitleOfIndividualAxis_BAE518E62A092CB019FC272271CF4635" xlink:type="arc" />
    <link:label id="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8_terseLabel_en-US" xlink:label="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Relationship to Entity [Domain]</link:label>
    <link:label id="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8_label_en-US" xlink:label="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Relationship to Entity [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8" xlink:to="lab_us-gaap_TitleOfIndividualWithRelationshipToEntityDomain_1098A46035E3AF02B560272271CFB3F8" xlink:type="arc" />
    <link:label id="lab_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720_terseLabel_en-US" xlink:label="lab_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Executive</link:label>
    <link:label id="lab_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720_label_en-US" xlink:label="lab_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Executive Officer [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ExecutiveOfficerMember" xlink:label="loc_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720" xlink:to="lab_us-gaap_ExecutiveOfficerMember_DF0AB0E0083951AC6496272271CF6720" xlink:type="arc" />
    <link:label id="lab_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7_terseLabel_en-US" xlink:label="lab_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Director</link:label>
    <link:label id="lab_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7_label_en-US" xlink:label="lab_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Director [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DirectorMember" xlink:label="loc_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7" xlink:to="lab_us-gaap_DirectorMember_E6CD93AC550C77C0A7DB272271CF30D7" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A_verboseLabel_en-US" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Reserved shares for issuance to key employees (shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A_label_en-US" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A" xlink:to="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_B500EBBE33E264EC2567272271D5AA7A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares of stock based compensation issued during the period (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod_FD4B474CBDA5B5FEE5AE272271D5EDE8" xlink:type="arc" />
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1_terseLabel_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Price per share (usd per share)</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1_label_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Per Share Price</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1_documentation_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share Based Compensation Arrangement By Share Based Payment Award Per Share Price</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice" xlink:label="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1" xlink:to="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice_5F6FB6D9526E274E7BCE272438D518F1" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83_terseLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock issued and sold (shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, Share-based Compensation, Gross</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensationGross_3124412B5F5D797D743A272271D5CA83" xlink:type="arc" />
    <link:label id="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0_terseLabel_en-US" xlink:label="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of recently retired members of the board of directors (director)</link:label>
    <link:label id="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0_label_en-US" xlink:label="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Recently Retired Members of the Board</link:label>
    <link:label id="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0_documentation_en-US" xlink:label="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of Recently Retired Members of the Board</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_NumberofRecentlyRetiredMembersoftheBoard" xlink:label="loc_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0" xlink:to="lab_oesx_NumberofRecentlyRetiredMembersoftheBoard_A79AFA2414D5784FB2D4272271D5BAB0" xlink:type="arc" />
    <link:label id="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB_terseLabel_en-US" xlink:label="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Closing common stock price (usd per share)</link:label>
    <link:label id="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB_label_en-US" xlink:label="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Of Closing Common Stock Price</link:label>
    <link:label id="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB_documentation_en-US" xlink:label="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Fair value of closing common stock price.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_FairValueOfClosingCommonStockPrice" xlink:label="loc_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB" xlink:to="lab_oesx_FairValueOfClosingCommonStockPrice_26DF1C59741E5B0A2F4D272271D595BB" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53_verboseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Compensation cost related to non-vested common stock-based compensation</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_C12ACD269112AEF9BA91272271D5DD53" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average expected term</link:label>
    <link:label id="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90_label_en-US" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_B278F25A579DCCBFA60B272271D56C90" xlink:type="arc" />
    <link:label id="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB_terseLabel_en-US" xlink:label="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred stock-based compensation related to grants of restricted shares, period of recognition</link:label>
    <link:label id="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB_label_en-US" xlink:label="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement With Individual Compensation Expense Period of Recognition</link:label>
    <link:label id="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB_documentation_en-US" xlink:label="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred compensation arrangement with individual compensation expense period of recognition.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition" xlink:label="loc_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB" xlink:to="lab_oesx_DeferredCompensationArrangementWithIndividualCompensationExpensePeriodOfRecognition_84A65CD54ACAA2490357272271D5BBDB" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7_terseLabel_en-US" xlink:label="lab_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred stock-based compensation related to grants of restricted shares</link:label>
    <link:label id="lab_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7_label_en-US" xlink:label="lab_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Compensation Arrangement with Individual, Compensation Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense" xlink:label="loc_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7" xlink:to="lab_us-gaap_DeferredCompensationArrangementWithIndividualCompensationExpense_81A1A7E6B63910E5578C272271D5A7E7" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_DB930C5F42F86EF73D28A6C144279531_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_019DB8F6E6A050D99FAB24F2049DF1C7" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Segment reporting information</link:label>
    <link:label id="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_DB930C5F42F86EF73D28A6C144279531_label_en-US" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_019DB8F6E6A050D99FAB24F2049DF1C7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_019DB8F6E6A050D99FAB24F2049DF1C7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_019DB8F6E6A050D99FAB24F2049DF1C7" xlink:to="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_019DB8F6E6A050D99FAB24F2049DF1C7" xlink:type="arc" />
    <link:label id="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_B1D43F355DF9CC545EA43D577D263105_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_F7647AA38AB4531D9DE558BAAD218E71" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Compensation and benefits</link:label>
    <link:label id="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_B1D43F355DF9CC545EA43D577D263105_label_en-US" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_F7647AA38AB4531D9DE558BAAD218E71" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Employee-related Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_F7647AA38AB4531D9DE558BAAD218E71" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent_F7647AA38AB4531D9DE558BAAD218E71" xlink:to="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_F7647AA38AB4531D9DE558BAAD218E71" xlink:type="arc" />
    <link:label id="lab_us-gaap_SalesAndExciseTaxPayableCurrent_9657A7ABCF94F281E4E73D57817F7B11_terseLabel_en-US" xlink:label="lab_us-gaap_SalesAndExciseTaxPayableCurrent_2957089EFC0B5AF69E10947AA3F9E3BB" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sales tax</link:label>
    <link:label id="lab_us-gaap_SalesAndExciseTaxPayableCurrent_9657A7ABCF94F281E4E73D57817F7B11_label_en-US" xlink:label="lab_us-gaap_SalesAndExciseTaxPayableCurrent_2957089EFC0B5AF69E10947AA3F9E3BB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales and Excise Tax Payable, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SalesAndExciseTaxPayableCurrent" xlink:label="loc_us-gaap_SalesAndExciseTaxPayableCurrent_2957089EFC0B5AF69E10947AA3F9E3BB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SalesAndExciseTaxPayableCurrent_2957089EFC0B5AF69E10947AA3F9E3BB" xlink:to="lab_us-gaap_SalesAndExciseTaxPayableCurrent_2957089EFC0B5AF69E10947AA3F9E3BB" xlink:type="arc" />
    <link:label id="lab_oesx_AccruedContractCostsCurrent_FDCB55C89B4CC5916C8B3D578604C0B7_terseLabel_en-US" xlink:label="lab_oesx_AccruedContractCostsCurrent_E9042E6BA68D550A9B3FB5C61218BFBE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Contract costs</link:label>
    <link:label id="lab_oesx_AccruedContractCostsCurrent_FDCB55C89B4CC5916C8B3D578604C0B7_label_en-US" xlink:label="lab_oesx_AccruedContractCostsCurrent_E9042E6BA68D550A9B3FB5C61218BFBE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Contract Costs, Current</link:label>
    <link:label id="lab_oesx_AccruedContractCostsCurrent_FDCB55C89B4CC5916C8B3D578604C0B7_documentation_en-US" xlink:label="lab_oesx_AccruedContractCostsCurrent_E9042E6BA68D550A9B3FB5C61218BFBE" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accrued Contract Costs, Current</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AccruedContractCostsCurrent" xlink:label="loc_oesx_AccruedContractCostsCurrent_E9042E6BA68D550A9B3FB5C61218BFBE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AccruedContractCostsCurrent_E9042E6BA68D550A9B3FB5C61218BFBE" xlink:to="lab_oesx_AccruedContractCostsCurrent_E9042E6BA68D550A9B3FB5C61218BFBE" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedProfessionalFeesCurrent_EBBD98984AF5AFA2BB2C3D578ACBB555_terseLabel_en-US" xlink:label="lab_us-gaap_AccruedProfessionalFeesCurrent_11436B4B1D9C5C9A9732EF26A8F977C1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Legal and professional fees</link:label>
    <link:label id="lab_us-gaap_AccruedProfessionalFeesCurrent_EBBD98984AF5AFA2BB2C3D578ACBB555_label_en-US" xlink:label="lab_us-gaap_AccruedProfessionalFeesCurrent_11436B4B1D9C5C9A9732EF26A8F977C1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Professional Fees, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccruedProfessionalFeesCurrent" xlink:label="loc_us-gaap_AccruedProfessionalFeesCurrent_11436B4B1D9C5C9A9732EF26A8F977C1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedProfessionalFeesCurrent_11436B4B1D9C5C9A9732EF26A8F977C1" xlink:to="lab_us-gaap_AccruedProfessionalFeesCurrent_11436B4B1D9C5C9A9732EF26A8F977C1" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_AFE8F459AC0F4E0784473D578FA42CE1_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_BB5B9BE19FCF592C90A3BCAB24977A33" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Warranty</link:label>
    <link:label id="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_AFE8F459AC0F4E0784473D578FA42CE1_label_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_BB5B9BE19FCF592C90A3BCAB24977A33" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product Warranty Accrual, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyAccrualClassifiedCurrent" xlink:label="loc_us-gaap_ProductWarrantyAccrualClassifiedCurrent_BB5B9BE19FCF592C90A3BCAB24977A33" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrualClassifiedCurrent_BB5B9BE19FCF592C90A3BCAB24977A33" xlink:to="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_BB5B9BE19FCF592C90A3BCAB24977A33" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherAccruedLiabilitiesCurrent_8160DE16D4DFE2E613CF3D57948795F7_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAccruedLiabilitiesCurrent_F2ADF523AD065A6BBC797B895970AFDE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other accruals</link:label>
    <link:label id="lab_us-gaap_OtherAccruedLiabilitiesCurrent_8160DE16D4DFE2E613CF3D57948795F7_label_en-US" xlink:label="lab_us-gaap_OtherAccruedLiabilitiesCurrent_F2ADF523AD065A6BBC797B895970AFDE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Accrued Liabilities, Current</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent_F2ADF523AD065A6BBC797B895970AFDE" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAccruedLiabilitiesCurrent_F2ADF523AD065A6BBC797B895970AFDE" xlink:to="lab_us-gaap_OtherAccruedLiabilitiesCurrent_F2ADF523AD065A6BBC797B895970AFDE" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedLiabilitiesCurrent_B1D75789BAA43AF9AD2B3D57993A7DF6_totalLabel_en-US" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent_BC00FED1C61A5C229104C3FD4C8BB469" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent_BC00FED1C61A5C229104C3FD4C8BB469" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent_BC00FED1C61A5C229104C3FD4C8BB469" xlink:to="lab_us-gaap_AccruedLiabilitiesCurrent_BC00FED1C61A5C229104C3FD4C8BB469" xlink:type="arc" />
    <link:label id="lab_us-gaap_LossContingencyAccrualAtCarryingValue_AE51B2ECE67A99287F403D5971AF91CF_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingencyAccrualAtCarryingValue_E9A9C859D66254C9B8FEAC578D4BB072" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loss contingency</link:label>
    <link:label id="lab_us-gaap_LossContingencyAccrualAtCarryingValue_AE51B2ECE67A99287F403D5971AF91CF_label_en-US" xlink:label="lab_us-gaap_LossContingencyAccrualAtCarryingValue_E9A9C859D66254C9B8FEAC578D4BB072" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Loss Contingency Accrual</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LossContingencyAccrualAtCarryingValue" xlink:label="loc_us-gaap_LossContingencyAccrualAtCarryingValue_E9A9C859D66254C9B8FEAC578D4BB072" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingencyAccrualAtCarryingValue_E9A9C859D66254C9B8FEAC578D4BB072" xlink:to="lab_us-gaap_LossContingencyAccrualAtCarryingValue_E9A9C859D66254C9B8FEAC578D4BB072" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfDebtTableTextBlock_AA95CA52888A389CD67FA6C1460F5A08_verboseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfDebtTableTextBlock_5A7C2391719E5D389F940599E52A307A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Long-term debt</link:label>
    <link:label id="lab_us-gaap_ScheduleOfDebtTableTextBlock_AA95CA52888A389CD67FA6C1460F5A08_label_en-US" xlink:label="lab_us-gaap_ScheduleOfDebtTableTextBlock_5A7C2391719E5D389F940599E52A307A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Debt [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfDebtTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDebtTableTextBlock_5A7C2391719E5D389F940599E52A307A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDebtTableTextBlock_5A7C2391719E5D389F940599E52A307A" xlink:to="lab_us-gaap_ScheduleOfDebtTableTextBlock_5A7C2391719E5D389F940599E52A307A" xlink:type="arc" />
    <link:label id="lab_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4_verboseLabel_en-US" xlink:label="lab_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Product revenue</link:label>
    <link:label id="lab_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4_label_en-US" xlink:label="lab_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales Revenue, Goods, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SalesRevenueGoodsNet" xlink:label="loc_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4" xlink:to="lab_us-gaap_SalesRevenueGoodsNet_23178646310E4C7B80FEE2B94D8D01A4" xlink:type="arc" />
    <link:label id="lab_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9_verboseLabel_en-US" xlink:label="lab_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Service revenue</link:label>
    <link:label id="lab_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9_label_en-US" xlink:label="lab_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sales Revenue, Services, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SalesRevenueServicesNet" xlink:label="loc_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9" xlink:to="lab_us-gaap_SalesRevenueServicesNet_4B0CC22236F3D92DB224E2B94D8EEDA9" xlink:type="arc" />
    <link:label id="lab_us-gaap_Revenues_9E1710313F3E0E145E65E2B94D8E042D_totalLabel_en-US" xlink:label="lab_us-gaap_Revenues_9E1710313F3E0E145E65E2B94D8E042D" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total revenue</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_Revenues" xlink:label="loc_us-gaap_Revenues_9E1710313F3E0E145E65E2B94D8E042D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Revenues_9E1710313F3E0E145E65E2B94D8E042D" xlink:to="lab_us-gaap_Revenues_9E1710313F3E0E145E65E2B94D8E042D" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8_verboseLabel_en-US" xlink:label="lab_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cost of product revenue</link:label>
    <link:label id="lab_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8_label_en-US" xlink:label="lab_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cost of Goods Sold</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CostOfGoodsSold" xlink:label="loc_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8" xlink:to="lab_us-gaap_CostOfGoodsSold_A2F89C3A747DE9B37035E2B94D8E16B8" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E_verboseLabel_en-US" xlink:label="lab_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cost of service revenue</link:label>
    <link:label id="lab_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E_label_en-US" xlink:label="lab_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cost of Services</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CostOfServices" xlink:label="loc_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E" xlink:to="lab_us-gaap_CostOfServices_90BCDC6E52DA687948BDE2B94D8ED74E" xlink:type="arc" />
    <link:label id="lab_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A_totalLabel_en-US" xlink:label="lab_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total cost of revenue</link:label>
    <link:label id="lab_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A_label_en-US" xlink:label="lab_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cost of Revenue</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CostOfRevenue" xlink:label="loc_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A" xlink:to="lab_us-gaap_CostOfRevenue_E93021E682F113E68804E2B94D8ED24A" xlink:type="arc" />
    <link:label id="lab_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2_totalLabel_en-US" xlink:label="lab_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Gross profit</link:label>
    <link:label id="lab_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2_label_en-US" xlink:label="lab_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Gross Profit</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_GrossProfit" xlink:label="loc_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2" xlink:to="lab_us-gaap_GrossProfit_DB4779BDAD8CF1CAA777E2B94D8E6BD2" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E_verboseLabel_en-US" xlink:label="lab_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Operating expenses:</link:label>
    <link:label id="lab_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E_label_en-US" xlink:label="lab_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Expenses [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E" xlink:to="lab_us-gaap_OperatingExpensesAbstract_6F2D2A1630206FD2B582E2B94D8EA07E" xlink:type="arc" />
    <link:label id="lab_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67_verboseLabel_en-US" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">General and administrative</link:label>
    <link:label id="lab_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67_label_en-US" xlink:label="lab_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">General and Administrative Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_GeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67" xlink:to="lab_us-gaap_GeneralAndAdministrativeExpense_4739D278AF8756D25253E2B94D8EEA67" xlink:type="arc" />
    <link:label id="lab_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205_verboseLabel_en-US" xlink:label="lab_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sales and marketing</link:label>
    <link:label id="lab_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205_label_en-US" xlink:label="lab_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Selling and Marketing Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SellingAndMarketingExpense" xlink:label="loc_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205" xlink:to="lab_us-gaap_SellingAndMarketingExpense_452AE6A0D7B75B452CCDE2B94D8E6205" xlink:type="arc" />
    <link:label id="lab_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6_verboseLabel_en-US" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Research and development</link:label>
    <link:label id="lab_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6_label_en-US" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Research and Development Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6" xlink:to="lab_us-gaap_ResearchAndDevelopmentExpense_35E8F3F1C26C395E0FB0E2B94D8EFBC6" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975_totalLabel_en-US" xlink:label="lab_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total operating expenses</link:label>
    <link:label id="lab_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975_label_en-US" xlink:label="lab_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Expenses</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingExpenses" xlink:label="loc_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975" xlink:to="lab_us-gaap_OperatingExpenses_7E4183F5B52CA27DD635E2B94D8EC975" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingIncomeLoss_24814320B7ABCA0D0151E2B94D8EEE23_totalLabel_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_24814320B7ABCA0D0151E2B94D8EEE23" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Loss from operations</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_24814320B7ABCA0D0151E2B94D8EEE23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss_24814320B7ABCA0D0151E2B94D8EEE23" xlink:to="lab_us-gaap_OperatingIncomeLoss_24814320B7ABCA0D0151E2B94D8EEE23" xlink:type="arc" />
    <link:label id="lab_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9_verboseLabel_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other income (expense):</link:label>
    <link:label id="lab_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9_label_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Nonoperating Income (Expense) [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NonoperatingIncomeExpenseAbstract" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9" xlink:to="lab_us-gaap_NonoperatingIncomeExpenseAbstract_9DBF6B3725269416E37BE2B94D8E46B9" xlink:type="arc" />
    <link:label id="lab_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F_terseLabel_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other income</link:label>
    <link:label id="lab_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F_label_en-US" xlink:label="lab_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Nonoperating Income</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_OtherNonoperatingIncome" xlink:label="loc_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F" xlink:to="lab_us-gaap_OtherNonoperatingIncome_45BC0D425D0C91B79BB4E2B94D8EF92F" xlink:type="arc" />
    <link:label id="lab_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF_negatedLabel_en-US" xlink:label="lab_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Interest expense</link:label>
    <link:label id="lab_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF_label_en-US" xlink:label="lab_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Expense</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF" xlink:to="lab_us-gaap_InterestExpense_9E830838E78B8EDFE773E2B94D8EF5FF" xlink:type="arc" />
    <link:label id="lab_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E_terseLabel_en-US" xlink:label="lab_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest income</link:label>
    <link:label id="lab_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E_label_en-US" xlink:label="lab_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Income, Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InvestmentIncomeInterest" xlink:label="loc_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E" xlink:to="lab_us-gaap_InvestmentIncomeInterest_0B3B294D31438EC9180EE2B94D8E8A5E" xlink:type="arc" />
    <link:label id="lab_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382_totalLabel_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total other income (expense)</link:label>
    <link:label id="lab_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382_label_en-US" xlink:label="lab_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Nonoperating Income (Expense)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NonoperatingIncomeExpense" xlink:label="loc_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382" xlink:to="lab_us-gaap_NonoperatingIncomeExpense_23424A7351D4D5E6DF60E2B94D8E2382" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97_totalLabel_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Loss before income tax</link:label>
    <link:label id="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97_label_en-US" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments_5FC44B39622E2A786D75E2B94D8E5D97" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D_verboseLabel_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Income tax expense (benefit)</link:label>
    <link:label id="lab_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D_label_en-US" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax Expense (Benefit)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D" xlink:to="lab_us-gaap_IncomeTaxExpenseBenefit_7415F8556A35A0DC1BB0E2B94D8E186D" xlink:type="arc" />
    <link:label id="lab_us-gaap_NetIncomeLoss_3BB8EA2E9ECA1EB99C13E2B94D8F9EB8_totalLabel_en-US" xlink:label="lab_us-gaap_NetIncomeLoss_3BB8EA2E9ECA1EB99C13E2B94D8F9EB8" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loss and comprehensive loss</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss_3BB8EA2E9ECA1EB99C13E2B94D8F9EB8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss_3BB8EA2E9ECA1EB99C13E2B94D8F9EB8" xlink:to="lab_us-gaap_NetIncomeLoss_3BB8EA2E9ECA1EB99C13E2B94D8F9EB8" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareBasic_14CAA45791B280E8B438E2B94D8FCD88_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareBasic_14CAA45791B280E8B438E2B94D8FCD88" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Basic net loss per share attributable to common shareholders (in dollars per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerShareBasic" xlink:label="loc_us-gaap_EarningsPerShareBasic_14CAA45791B280E8B438E2B94D8FCD88" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasic_14CAA45791B280E8B438E2B94D8FCD88" xlink:to="lab_us-gaap_EarningsPerShareBasic_14CAA45791B280E8B438E2B94D8FCD88" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerShareDiluted_02D4EFE2F2ECFCE46DDEE2B94D8F7BD6_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerShareDiluted_02D4EFE2F2ECFCE46DDEE2B94D8F7BD6" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Diluted net loss per share (in dollars per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerShareDiluted" xlink:label="loc_us-gaap_EarningsPerShareDiluted_02D4EFE2F2ECFCE46DDEE2B94D8F7BD6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareDiluted_02D4EFE2F2ECFCE46DDEE2B94D8F7BD6" xlink:to="lab_us-gaap_EarningsPerShareDiluted_02D4EFE2F2ECFCE46DDEE2B94D8F7BD6" xlink:type="arc" />
    <link:label id="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_268AB440988DCD922960E2B94D8FB904_verboseLabel_en-US" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_268AB440988DCD922960E2B94D8FB904" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Weighted-average common shares and share equivalents outstanding (in shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:label="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_268AB440988DCD922960E2B94D8FB904" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_268AB440988DCD922960E2B94D8FB904" xlink:to="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_268AB440988DCD922960E2B94D8FB904" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD_terseLabel_en-US" xlink:label="lab_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Products and Services [Axis]</link:label>
    <link:label id="lab_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD_label_en-US" xlink:label="lab_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Products and Services [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductOrServiceAxis" xlink:label="loc_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD" xlink:to="lab_us-gaap_ProductOrServiceAxis_17187740C6DDF782473E202AA3D2A0AD" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57_terseLabel_en-US" xlink:label="lab_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Products and Services [Domain]</link:label>
    <link:label id="lab_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57_label_en-US" xlink:label="lab_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Products and Services [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductsAndServicesDomain" xlink:label="loc_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57" xlink:to="lab_us-gaap_ProductsAndServicesDomain_64B805E9E96AE1689A3D202AA3D34A57" xlink:type="arc" />
    <link:label id="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485_terseLabel_en-US" xlink:label="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">High Intensity Fluorescent Lighting Products</link:label>
    <link:label id="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485_label_en-US" xlink:label="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">High Intensity Fluorescent Lighting Products [Member]</link:label>
    <link:label id="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485_documentation_en-US" xlink:label="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">High Intensity Fluorescent Lighting Products [Member]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_HighIntensityFluorescentLightingProductsMember" xlink:label="loc_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485" xlink:to="lab_oesx_HighIntensityFluorescentLightingProductsMember_7F5DB0ED5245E80B6105202AA3D33485" xlink:type="arc" />
    <link:label id="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C_verboseLabel_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable are due, minimum period (days)</link:label>
    <link:label id="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C_label_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivables Due Minimum Period</link:label>
    <link:label id="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C_documentation_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accounts receivables due minimum period.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AccountsReceivablesDueMinimumPeriod" xlink:label="loc_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C" xlink:to="lab_oesx_AccountsReceivablesDueMinimumPeriod_7E1C0E07BA88423B888F202AA3D3548C" xlink:type="arc" />
    <link:label id="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC_verboseLabel_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable are due, maximum period (days)</link:label>
    <link:label id="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC_label_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounts Receivables Due Maximum Period</link:label>
    <link:label id="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC_documentation_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accounts receivables due maximum period.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AccountsReceivablesDueMaximumPeriod" xlink:label="loc_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC" xlink:to="lab_oesx_AccountsReceivablesDueMaximumPeriod_EC22A7147658FC528D74202AA3D313CC" xlink:type="arc" />
    <link:label id="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698_terseLabel_en-US" xlink:label="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Length of time of inventory usage considered for inventory reserve (months)</link:label>
    <link:label id="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698_label_en-US" xlink:label="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory Reserve, Length of Time of Inventory Usage Considered</link:label>
    <link:label id="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698_documentation_en-US" xlink:label="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Inventory Reserve, Length of Time of Inventory Usage Considered</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered" xlink:label="loc_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698" xlink:to="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_629BAA8998E574CEA2DC202AA3D3C698" xlink:type="arc" />
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC_terseLabel_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization</link:label>
    <link:label id="lab_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC_label_en-US" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Amortization of Intangible Assets</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC" xlink:to="lab_us-gaap_AmortizationOfIntangibleAssets_F1194D6D99DD4FB5D2E2202AA3D30DAC" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Intangible assets, estimated economic useful life (years)</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Asset, Useful Life</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife_755129754DDD38378E8B202AA3D39E23" xlink:type="arc" />
    <link:label id="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17_terseLabel_en-US" xlink:label="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Limited warranty term (years)</link:label>
    <link:label id="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17_label_en-US" xlink:label="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Limited Warranty, Term</link:label>
    <link:label id="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17_documentation_en-US" xlink:label="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Limited Warranty, Term</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_LimitedWarrantyTerm" xlink:label="loc_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17" xlink:to="lab_oesx_LimitedWarrantyTerm_8F0EBDAC3229E7CCB257202AA3D37A17" xlink:type="arc" />
    <link:label id="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243_verboseLabel_en-US" xlink:label="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Power purchase agreement product revenue is recognized term (years)</link:label>
    <link:label id="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243_label_en-US" xlink:label="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Power Purchase Agreement Product Revenue Recognizable Term</link:label>
    <link:label id="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243_documentation_en-US" xlink:label="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Power purchase agreement product revenue recognizable term.</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm" xlink:label="loc_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243" xlink:to="lab_oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm_EB620800E51F067B0FFE202AA3D35243" xlink:type="arc" />
    <link:label id="lab_us-gaap_SignificantAccountingPoliciesTextBlock_252CAECB9A6C1092C6EDA6C1410A71FB_verboseLabel_en-US" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock_588C996F867351D5875CBB2CE279FFF5" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES</link:label>
    <link:label id="lab_us-gaap_SignificantAccountingPoliciesTextBlock_252CAECB9A6C1092C6EDA6C1410A71FB_label_en-US" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock_588C996F867351D5875CBB2CE279FFF5" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Significant Accounting Policies [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_SignificantAccountingPoliciesTextBlock_588C996F867351D5875CBB2CE279FFF5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SignificantAccountingPoliciesTextBlock_588C996F867351D5875CBB2CE279FFF5" xlink:to="lab_us-gaap_SignificantAccountingPoliciesTextBlock_588C996F867351D5875CBB2CE279FFF5" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product Warranty Liability [Table]</link:label>
    <link:label id="lab_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D_label_en-US" xlink:label="lab_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product Warranty Liability [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyLiabilityTable" xlink:label="loc_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D" xlink:to="lab_us-gaap_ProductWarrantyLiabilityTable_DF508803BBAA77968A74214A182BBD1D" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product Warranty Liability [Line Items]</link:label>
    <link:label id="lab_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72_label_en-US" xlink:label="lab_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product Warranty Liability [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyLiabilityLineItems" xlink:label="loc_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72" xlink:to="lab_us-gaap_ProductWarrantyLiabilityLineItems_EBC1F1337B7050A457B3214A182B0D72" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in warranty accrual</link:label>
    <link:label id="lab_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299_label_en-US" xlink:label="lab_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Product Warranties Disclosures [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantiesDisclosuresAbstract" xlink:label="loc_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299" xlink:to="lab_us-gaap_ProductWarrantiesDisclosuresAbstract_2897C36CECE8C57A87E5214A182B7299" xlink:type="arc" />
    <link:label id="lab_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3_terseLabel_en-US" xlink:label="lab_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Movement in Standard Product Warranty Accrual [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3_label_en-US" xlink:label="lab_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Movement in Standard Product Warranty Accrual [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_MovementInStandardProductWarrantyAccrualRollForward" xlink:label="loc_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3" xlink:to="lab_us-gaap_MovementInStandardProductWarrantyAccrualRollForward_A9369E2BE1EBED58A84A214A182B0EA3" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC_periodStartLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Beginning of period</link:label>
    <link:label id="lab_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC_label_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Standard and Extended Product Warranty Accrual</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyAccrual" xlink:label="loc_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC" xlink:to="lab_us-gaap_ProductWarrantyAccrual_1A0AD7212688BE2DAC06214A182BC7DC" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0_verboseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Provision to product cost of revenue</link:label>
    <link:label id="lab_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0_label_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Standard and Extended Product Warranty Accrual, Increase for Warranties Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyAccrualWarrantiesIssued" xlink:label="loc_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0" xlink:to="lab_us-gaap_ProductWarrantyAccrualWarrantiesIssued_B4B7131402E697042B0C214A182CA0C0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Charges</link:label>
    <link:label id="lab_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E_label_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Standard and Extended Product Warranty Accrual, Increase (Decrease) for Preexisting Warranties</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease" xlink:label="loc_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E" xlink:to="lab_us-gaap_ProductWarrantyAccrualPreexistingIncreaseDecrease_8C783A09DCD5AC19D368214A182C689E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrual_BEB2BB3952F6872BD842214A182CDB81_periodEndLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrual_BEB2BB3952F6872BD842214A182CDB81" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">End of period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyAccrual" xlink:label="loc_us-gaap_ProductWarrantyAccrual_BEB2BB3952F6872BD842214A182CDB81" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrual_BEB2BB3952F6872BD842214A182CDB81" xlink:to="lab_us-gaap_ProductWarrantyAccrual_BEB2BB3952F6872BD842214A182CDB81" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrual_6183B5ABA53DE8768F8E214A182BD91A_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrual_6183B5ABA53DE8768F8E214A182BD91A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Product warranty accrual</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ProductWarrantyAccrual" xlink:label="loc_us-gaap_ProductWarrantyAccrual_6183B5ABA53DE8768F8E214A182BD91A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrual_6183B5ABA53DE8768F8E214A182BD91A" xlink:to="lab_us-gaap_ProductWarrantyAccrual_6183B5ABA53DE8768F8E214A182BD91A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_49878E1B1AE3EB5DB0F23D8438FA21DA_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_C07C8D8AFC7A5505B7358B9ECE78A9C0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_49878E1B1AE3EB5DB0F23D8438FA21DA_label_en-US" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_C07C8D8AFC7A5505B7358B9ECE78A9C0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Finite-Lived Intangible Assets [Table]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_C07C8D8AFC7A5505B7358B9ECE78A9C0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_C07C8D8AFC7A5505B7358B9ECE78A9C0" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_C07C8D8AFC7A5505B7358B9ECE78A9C0" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9BDDF54B3E0769DC49573D8438FA7464_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_A1CA548B5C3D5D7192A05EA37CDC3C16" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_9BDDF54B3E0769DC49573D8438FA7464_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_A1CA548B5C3D5D7192A05EA37CDC3C16" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets by Major Class [Axis]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_A1CA548B5C3D5D7192A05EA37CDC3C16" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_A1CA548B5C3D5D7192A05EA37CDC3C16" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_A1CA548B5C3D5D7192A05EA37CDC3C16" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B768B1522E200F670B5D3D8438FA5155_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_84FD60FA5D605068A04F47FB9CC6C360" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_B768B1522E200F670B5D3D8438FA5155_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_84FD60FA5D605068A04F47FB9CC6C360" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Major Class Name [Domain]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_84FD60FA5D605068A04F47FB9CC6C360" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_84FD60FA5D605068A04F47FB9CC6C360" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_84FD60FA5D605068A04F47FB9CC6C360" xlink:type="arc" />
    <link:label id="lab_us-gaap_PatentsMember_866ED1A1DA4E166EEFE83D8438FA01BC_terseLabel_en-US" xlink:label="lab_us-gaap_PatentsMember_F36C77B580E052BCB99C12C357AAFB58" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Patents</link:label>
    <link:label id="lab_us-gaap_PatentsMember_866ED1A1DA4E166EEFE83D8438FA01BC_label_en-US" xlink:label="lab_us-gaap_PatentsMember_F36C77B580E052BCB99C12C357AAFB58" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Patents [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PatentsMember" xlink:label="loc_us-gaap_PatentsMember_F36C77B580E052BCB99C12C357AAFB58" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PatentsMember_F36C77B580E052BCB99C12C357AAFB58" xlink:to="lab_us-gaap_PatentsMember_F36C77B580E052BCB99C12C357AAFB58" xlink:type="arc" />
    <link:label id="lab_us-gaap_LicensingAgreementsMember_CA7DD332092FA1C578EC3D8438FA5324_terseLabel_en-US" xlink:label="lab_us-gaap_LicensingAgreementsMember_97B17B1B53FB55F19B0035C988794F7B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Licenses</link:label>
    <link:label id="lab_us-gaap_LicensingAgreementsMember_CA7DD332092FA1C578EC3D8438FA5324_label_en-US" xlink:label="lab_us-gaap_LicensingAgreementsMember_97B17B1B53FB55F19B0035C988794F7B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Licensing Agreements [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_LicensingAgreementsMember" xlink:label="loc_us-gaap_LicensingAgreementsMember_97B17B1B53FB55F19B0035C988794F7B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LicensingAgreementsMember_97B17B1B53FB55F19B0035C988794F7B" xlink:to="lab_us-gaap_LicensingAgreementsMember_97B17B1B53FB55F19B0035C988794F7B" xlink:type="arc" />
    <link:label id="lab_us-gaap_TrademarksAndTradeNamesMember_ECEE3FFEAB11C02DD4F53D8438FA833B_terseLabel_en-US" xlink:label="lab_us-gaap_TrademarksAndTradeNamesMember_452255C0CF235151B119EE40EFA7AE6B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Trade name and trademarks</link:label>
    <link:label id="lab_us-gaap_TrademarksAndTradeNamesMember_ECEE3FFEAB11C02DD4F53D8438FA833B_label_en-US" xlink:label="lab_us-gaap_TrademarksAndTradeNamesMember_452255C0CF235151B119EE40EFA7AE6B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Trademarks and Trade Names [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_TrademarksAndTradeNamesMember" xlink:label="loc_us-gaap_TrademarksAndTradeNamesMember_452255C0CF235151B119EE40EFA7AE6B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TrademarksAndTradeNamesMember_452255C0CF235151B119EE40EFA7AE6B" xlink:to="lab_us-gaap_TrademarksAndTradeNamesMember_452255C0CF235151B119EE40EFA7AE6B" xlink:type="arc" />
    <link:label id="lab_us-gaap_CustomerRelationshipsMember_BA071A1001D8249AB05C3D8438FB73D1_terseLabel_en-US" xlink:label="lab_us-gaap_CustomerRelationshipsMember_8BAB6E10E59A5BB7987E6585BA5B6D9C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Customer relationships</link:label>
    <link:label id="lab_us-gaap_CustomerRelationshipsMember_BA071A1001D8249AB05C3D8438FB73D1_label_en-US" xlink:label="lab_us-gaap_CustomerRelationshipsMember_8BAB6E10E59A5BB7987E6585BA5B6D9C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Customer Relationships [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="loc_us-gaap_CustomerRelationshipsMember_8BAB6E10E59A5BB7987E6585BA5B6D9C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CustomerRelationshipsMember_8BAB6E10E59A5BB7987E6585BA5B6D9C" xlink:to="lab_us-gaap_CustomerRelationshipsMember_8BAB6E10E59A5BB7987E6585BA5B6D9C" xlink:type="arc" />
    <link:label id="lab_us-gaap_DevelopedTechnologyRightsMember_D73100C0A85C05DE5C783D8438FB2DC9_terseLabel_en-US" xlink:label="lab_us-gaap_DevelopedTechnologyRightsMember_D81B547658F35742A87D52BE7199580B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Developed technology</link:label>
    <link:label id="lab_us-gaap_DevelopedTechnologyRightsMember_D73100C0A85C05DE5C783D8438FB2DC9_label_en-US" xlink:label="lab_us-gaap_DevelopedTechnologyRightsMember_D81B547658F35742A87D52BE7199580B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Developed Technology Rights [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DevelopedTechnologyRightsMember" xlink:label="loc_us-gaap_DevelopedTechnologyRightsMember_D81B547658F35742A87D52BE7199580B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DevelopedTechnologyRightsMember_D81B547658F35742A87D52BE7199580B" xlink:to="lab_us-gaap_DevelopedTechnologyRightsMember_D81B547658F35742A87D52BE7199580B" xlink:type="arc" />
    <link:label id="lab_us-gaap_NoncompeteAgreementsMember_4981BA07C1E7B2FE397A3D8438FB23ED_terseLabel_en-US" xlink:label="lab_us-gaap_NoncompeteAgreementsMember_98E075E0B98759E3B4EB40E8862F42C8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-competition agreement</link:label>
    <link:label id="lab_us-gaap_NoncompeteAgreementsMember_4981BA07C1E7B2FE397A3D8438FB23ED_label_en-US" xlink:label="lab_us-gaap_NoncompeteAgreementsMember_98E075E0B98759E3B4EB40E8862F42C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncompete Agreements [Member]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NoncompeteAgreementsMember" xlink:label="loc_us-gaap_NoncompeteAgreementsMember_98E075E0B98759E3B4EB40E8862F42C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncompeteAgreementsMember_98E075E0B98759E3B4EB40E8862F42C8" xlink:to="lab_us-gaap_NoncompeteAgreementsMember_98E075E0B98759E3B4EB40E8862F42C8" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_FAF79C6022A34EFB52513D8438FB41EA_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_961B9AEBF7555B02961011FB40F884F9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets [Line Items]</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_FAF79C6022A34EFB52513D8438FB41EA_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_961B9AEBF7555B02961011FB40F884F9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_961B9AEBF7555B02961011FB40F884F9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_961B9AEBF7555B02961011FB40F884F9" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems_961B9AEBF7555B02961011FB40F884F9" xlink:type="arc" />
    <link:label id="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_D73268FE8513C209C34B3D8438FBA0B0_terseLabel_en-US" xlink:label="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_1B7A67BB6BFC57B8B185C06CF6E3BB1F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Gross Carrying Amount</link:label>
    <link:label id="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_D73268FE8513C209C34B3D8438FBA0B0_label_en-US" xlink:label="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_1B7A67BB6BFC57B8B185C06CF6E3BB1F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived and Indefinite-Lived Intangible Assets, Gross</link:label>
    <link:label id="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_D73268FE8513C209C34B3D8438FBA0B0_documentation_en-US" xlink:label="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_1B7A67BB6BFC57B8B185C06CF6E3BB1F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Finite-Lived and Indefinite-Lived Intangible Assets, Gross</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross" xlink:label="loc_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_1B7A67BB6BFC57B8B185C06CF6E3BB1F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_1B7A67BB6BFC57B8B185C06CF6E3BB1F" xlink:to="lab_oesx_FiniteLivedandIndefiniteLivedIntangibleAssetsGross_1B7A67BB6BFC57B8B185C06CF6E3BB1F" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_D8F846D421D54B1BACBE3D8438FB4B2C_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_0B8ED118EAE35DB78C4AD6106231DD34" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Amortization</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_D8F846D421D54B1BACBE3D8438FB4B2C_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_0B8ED118EAE35DB78C4AD6106231DD34" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Accumulated Amortization</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_0B8ED118EAE35DB78C4AD6106231DD34" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_0B8ED118EAE35DB78C4AD6106231DD34" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_0B8ED118EAE35DB78C4AD6106231DD34" xlink:type="arc" />
    <link:label id="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_997697E2DCE467D74DCE3D8438FBD032_totalLabel_en-US" xlink:label="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_E6CDE12ECB2D5F7EB140C61C7D695F23" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwill" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_E6CDE12ECB2D5F7EB140C61C7D695F23" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwill_E6CDE12ECB2D5F7EB140C61C7D695F23" xlink:to="lab_us-gaap_IntangibleAssetsNetExcludingGoodwill_E6CDE12ECB2D5F7EB140C61C7D695F23" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_8F798322303DC0AB2B5F3D8438FBED2E_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_932807BA580159EF9B00E18C7BCB9B71" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Estimated Amortization Expense</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_8F798322303DC0AB2B5F3D8438FBED2E_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_932807BA580159EF9B00E18C7BCB9B71" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_932807BA580159EF9B00E18C7BCB9B71" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_932807BA580159EF9B00E18C7BCB9B71" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract_932807BA580159EF9B00E18C7BCB9B71" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_A107C174555E1CAA590C3D8438FB81E3_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_B5AAECD1AC415251B1924E8B06A91F7C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiscal 2017</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_A107C174555E1CAA590C3D8438FB81E3_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_B5AAECD1AC415251B1924E8B06A91F7C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_B5AAECD1AC415251B1924E8B06A91F7C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_B5AAECD1AC415251B1924E8B06A91F7C" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseRemainderOfFiscalYear_B5AAECD1AC415251B1924E8B06A91F7C" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_CBECAB7C5BB99C1683463D8438FBE5C6_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_8419BC2B340953AD8C34F76BD9C7D179" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiscal 2018</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_CBECAB7C5BB99C1683463D8438FBE5C6_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_8419BC2B340953AD8C34F76BD9C7D179" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_8419BC2B340953AD8C34F76BD9C7D179" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_8419BC2B340953AD8C34F76BD9C7D179" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths_8419BC2B340953AD8C34F76BD9C7D179" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_CC3F040235F03F11D84A3D8438FB2668_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_02DB62CE17285B999E574F5945E6D9B4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiscal 2019</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_CC3F040235F03F11D84A3D8438FB2668_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_02DB62CE17285B999E574F5945E6D9B4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Two</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_02DB62CE17285B999E574F5945E6D9B4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_02DB62CE17285B999E574F5945E6D9B4" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_02DB62CE17285B999E574F5945E6D9B4" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_799CD4AA228B521154873D8438FBAB52_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_5BD0F741F3C552BE996B49DC70ADB266" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiscal 2020</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_799CD4AA228B521154873D8438FBAB52_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_5BD0F741F3C552BE996B49DC70ADB266" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Three</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_5BD0F741F3C552BE996B49DC70ADB266" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_5BD0F741F3C552BE996B49DC70ADB266" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree_5BD0F741F3C552BE996B49DC70ADB266" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_DCCC640784830E8DA0BE3D8438FBF9AA_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_21455DE2D4A0580ABA5C23CB44A2C709" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiscal 2021</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_DCCC640784830E8DA0BE3D8438FBF9AA_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_21455DE2D4A0580ABA5C23CB44A2C709" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Four</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_21455DE2D4A0580ABA5C23CB44A2C709" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_21455DE2D4A0580ABA5C23CB44A2C709" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_21455DE2D4A0580ABA5C23CB44A2C709" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_BEDDF581C0B8D48811CB3D8438FBBE11_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_C8BB1BA1F8525B60B279C3A2742AA1C0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fiscal 2022</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_BEDDF581C0B8D48811CB3D8438FBBE11_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_C8BB1BA1F8525B60B279C3A2742AA1C0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, Year Five</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_C8BB1BA1F8525B60B279C3A2742AA1C0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_C8BB1BA1F8525B60B279C3A2742AA1C0" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive_C8BB1BA1F8525B60B279C3A2742AA1C0" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_87EDB89964952F0975B23D8438FB209C_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_D465E65E6AF154CEBBC665AB13028DBD" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Thereafter</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_87EDB89964952F0975B23D8438FB209C_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_D465E65E6AF154CEBBC665AB13028DBD" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Amortization Expense, after Year Five</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_D465E65E6AF154CEBBC665AB13028DBD" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_D465E65E6AF154CEBBC665AB13028DBD" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive_D465E65E6AF154CEBBC665AB13028DBD" xlink:type="arc" />
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_ED73A899E5A1BD415C9A3D8438FB75F5_totalLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet_8B0EC01F3DD15F9CBA634741BBD0D4F3" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_ED73A899E5A1BD415C9A3D8438FB75F5_label_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet_8B0EC01F3DD15F9CBA634741BBD0D4F3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finite-Lived Intangible Assets, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_8B0EC01F3DD15F9CBA634741BBD0D4F3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet_8B0EC01F3DD15F9CBA634741BBD0D4F3" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsNet_8B0EC01F3DD15F9CBA634741BBD0D4F3" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, par value (usd per share)</link:label>
    <link:label id="lab_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74_label_en-US" xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Par or Stated Value Per Share</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74" xlink:to="lab_us-gaap_PreferredStockParOrStatedValuePerShare_BFC5AC805BA950D22E379070FF81CC74" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares authorized (shares)</link:label>
    <link:label id="lab_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7_label_en-US" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Authorized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7" xlink:to="lab_us-gaap_PreferredStockSharesAuthorized_B38519E02DC44ACC46C29070FF8101B7" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares issued (shares)</link:label>
    <link:label id="lab_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B_label_en-US" xlink:label="lab_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="loc_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B" xlink:to="lab_us-gaap_PreferredStockSharesIssued_378DD05894A1D9924CDA9070FF824F9B" xlink:type="arc" />
    <link:label id="lab_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32_terseLabel_en-US" xlink:label="lab_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares outstanding (shares)</link:label>
    <link:label id="lab_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32_label_en-US" xlink:label="lab_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Outstanding</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32" xlink:to="lab_us-gaap_PreferredStockSharesOutstanding_976F3665FF27E790F5729070FF821A32" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, par value (usd per share)</link:label>
    <link:label id="lab_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314_label_en-US" xlink:label="lab_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, No Par Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockNoParValue" xlink:label="loc_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314" xlink:to="lab_us-gaap_CommonStockNoParValue_A4F37F0F8E61CE8D3A799070FF82B314" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares authorized (shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E" xlink:to="lab_us-gaap_CommonStockSharesAuthorized_D124889EFA89494631FB9070FF822A0E" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares issued (shares)</link:label>
    <link:label id="lab_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC_label_en-US" xlink:label="lab_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Issued</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC" xlink:to="lab_us-gaap_CommonStockSharesIssued_FF4DAB89148BA393765F9070FF82C9CC" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E_terseLabel_en-US" xlink:label="lab_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares outstanding (shares)</link:label>
    <link:label id="lab_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E_label_en-US" xlink:label="lab_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Shares, Outstanding</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharesOutstanding" xlink:label="loc_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E" xlink:to="lab_us-gaap_SharesOutstanding_46D315602DF95034241F9070FF82797E" xlink:type="arc" />
    <link:label id="lab_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6_terseLabel_en-US" xlink:label="lab_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Treasury stock, shares (shares)</link:label>
    <link:label id="lab_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6_label_en-US" xlink:label="lab_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Treasury Stock, Shares</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_TreasuryStockShares" xlink:label="loc_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6" xlink:to="lab_us-gaap_TreasuryStockShares_F52B87EE9863C0CF626F9070FF8257C6" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_5863E782824921662AD2A6C1441E0ABF_terseLabel_en-US" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_DA45B4BA5E7F5CF1823FEF019C17C370" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">STOCK OPTIONS AND RESTRICTED SHARES</link:label>
    <link:label id="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_5863E782824921662AD2A6C1441E0ABF_label_en-US" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_DA45B4BA5E7F5CF1823FEF019C17C370" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure of Compensation Related Costs, Share-based Payments [Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_DA45B4BA5E7F5CF1823FEF019C17C370" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_DA45B4BA5E7F5CF1823FEF019C17C370" xlink:to="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock_DA45B4BA5E7F5CF1823FEF019C17C370" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConsolidationPolicyTextBlock_4E9B4C5163B12A9C98643CC8428F0BDB_verboseLabel_en-US" xlink:label="lab_us-gaap_ConsolidationPolicyTextBlock_6002BAE576FE5B97AF447F03909B1199" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Principles of Consolidation</link:label>
    <link:label id="lab_us-gaap_ConsolidationPolicyTextBlock_4E9B4C5163B12A9C98643CC8428F0BDB_label_en-US" xlink:label="lab_us-gaap_ConsolidationPolicyTextBlock_6002BAE576FE5B97AF447F03909B1199" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Consolidation, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConsolidationPolicyTextBlock" xlink:label="loc_us-gaap_ConsolidationPolicyTextBlock_6002BAE576FE5B97AF447F03909B1199" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsolidationPolicyTextBlock_6002BAE576FE5B97AF447F03909B1199" xlink:to="lab_us-gaap_ConsolidationPolicyTextBlock_6002BAE576FE5B97AF447F03909B1199" xlink:type="arc" />
    <link:label id="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_F89841A777F5CA55EE763CC8428F8947_terseLabel_en-US" xlink:label="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_DF5C22C421C85FD2B236685A5D2D65C8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Reclassifications</link:label>
    <link:label id="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_F89841A777F5CA55EE763CC8428F8947_label_en-US" xlink:label="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_DF5C22C421C85FD2B236685A5D2D65C8" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Reclassification, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:label="loc_us-gaap_PriorPeriodReclassificationAdjustmentDescription_DF5C22C421C85FD2B236685A5D2D65C8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PriorPeriodReclassificationAdjustmentDescription_DF5C22C421C85FD2B236685A5D2D65C8" xlink:to="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription_DF5C22C421C85FD2B236685A5D2D65C8" xlink:type="arc" />
    <link:label id="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_F6D9146DC6C74A3C544E3CC8428F7688_verboseLabel_en-US" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_EB7ABC011FB95E6FB4BA01DE64C8217B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Basis of Presentation</link:label>
    <link:label id="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_F6D9146DC6C74A3C544E3CC8428F7688_label_en-US" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_EB7ABC011FB95E6FB4BA01DE64C8217B" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Basis of Accounting, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:label="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_EB7ABC011FB95E6FB4BA01DE64C8217B" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_EB7ABC011FB95E6FB4BA01DE64C8217B" xlink:to="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock_EB7ABC011FB95E6FB4BA01DE64C8217B" xlink:type="arc" />
    <link:label id="lab_us-gaap_UseOfEstimates_324199DEF81FF3B4C3453CC8428F94BE_verboseLabel_en-US" xlink:label="lab_us-gaap_UseOfEstimates_B1BB1C990F79515C97C491938DFA6F64" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Use of Estimates</link:label>
    <link:label id="lab_us-gaap_UseOfEstimates_324199DEF81FF3B4C3453CC8428F94BE_label_en-US" xlink:label="lab_us-gaap_UseOfEstimates_B1BB1C990F79515C97C491938DFA6F64" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Use of Estimates, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_UseOfEstimates" xlink:label="loc_us-gaap_UseOfEstimates_B1BB1C990F79515C97C491938DFA6F64" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UseOfEstimates_B1BB1C990F79515C97C491938DFA6F64" xlink:to="lab_us-gaap_UseOfEstimates_B1BB1C990F79515C97C491938DFA6F64" xlink:type="arc" />
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_8E36DED1B5AC0D4704BE3CC8428F667D_verboseLabel_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_0C9B26C150DB5AE9AECAF167ED1D9FF3" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents</link:label>
    <link:label id="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_8E36DED1B5AC0D4704BE3CC8428F667D_label_en-US" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_0C9B26C150DB5AE9AECAF167ED1D9FF3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock_0C9B26C150DB5AE9AECAF167ED1D9FF3" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock_0C9B26C150DB5AE9AECAF167ED1D9FF3" xlink:to="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock_0C9B26C150DB5AE9AECAF167ED1D9FF3" xlink:type="arc" />
    <link:label id="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy_72098F83E40290930EEB3CC8428F947A_verboseLabel_en-US" xlink:label="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy_A124C441B04E543FAEE5942F8E4EA397" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair Value of Financial Instruments</link:label>
    <link:label id="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy_72098F83E40290930EEB3CC8428F947A_label_en-US" xlink:label="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy_A124C441B04E543FAEE5942F8E4EA397" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value of Financial Instruments, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:label="loc_us-gaap_FairValueOfFinancialInstrumentsPolicy_A124C441B04E543FAEE5942F8E4EA397" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueOfFinancialInstrumentsPolicy_A124C441B04E543FAEE5942F8E4EA397" xlink:to="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy_A124C441B04E543FAEE5942F8E4EA397" xlink:type="arc" />
    <link:label id="lab_us-gaap_ReceivablesPolicyTextBlock_34ADA45FB2D0171F2BD63CC8428F63BA_verboseLabel_en-US" xlink:label="lab_us-gaap_ReceivablesPolicyTextBlock_F97A91BE2457516D9EBC88530D5F9B22" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts Receivable</link:label>
    <link:label id="lab_us-gaap_ReceivablesPolicyTextBlock_34ADA45FB2D0171F2BD63CC8428F63BA_label_en-US" xlink:label="lab_us-gaap_ReceivablesPolicyTextBlock_F97A91BE2457516D9EBC88530D5F9B22" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Receivables, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ReceivablesPolicyTextBlock" xlink:label="loc_us-gaap_ReceivablesPolicyTextBlock_F97A91BE2457516D9EBC88530D5F9B22" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReceivablesPolicyTextBlock_F97A91BE2457516D9EBC88530D5F9B22" xlink:to="lab_us-gaap_ReceivablesPolicyTextBlock_F97A91BE2457516D9EBC88530D5F9B22" xlink:type="arc" />
    <link:label id="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_468889BC2D72B9479D433CC84290E2EE_verboseLabel_en-US" xlink:label="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_B90BAA0F57C856749B2AE32F35DBF1D1" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Financing Receivables</link:label>
    <link:label id="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_468889BC2D72B9479D433CC84290E2EE_label_en-US" xlink:label="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_B90BAA0F57C856749B2AE32F35DBF1D1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Finance, Loans and Leases Receivable, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_FinanceLoansAndLeasesReceivablePolicy" xlink:label="loc_us-gaap_FinanceLoansAndLeasesReceivablePolicy_B90BAA0F57C856749B2AE32F35DBF1D1" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinanceLoansAndLeasesReceivablePolicy_B90BAA0F57C856749B2AE32F35DBF1D1" xlink:to="lab_us-gaap_FinanceLoansAndLeasesReceivablePolicy_B90BAA0F57C856749B2AE32F35DBF1D1" xlink:type="arc" />
    <link:label id="lab_us-gaap_InventoryPolicyTextBlock_5E8DC9C0CC840008311F3CC8429044B2_verboseLabel_en-US" xlink:label="lab_us-gaap_InventoryPolicyTextBlock_B534E7FFAEE059D7BF31A083E23C60AA" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Inventories</link:label>
    <link:label id="lab_us-gaap_InventoryPolicyTextBlock_5E8DC9C0CC840008311F3CC8429044B2_label_en-US" xlink:label="lab_us-gaap_InventoryPolicyTextBlock_B534E7FFAEE059D7BF31A083E23C60AA" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_InventoryPolicyTextBlock" xlink:label="loc_us-gaap_InventoryPolicyTextBlock_B534E7FFAEE059D7BF31A083E23C60AA" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryPolicyTextBlock_B534E7FFAEE059D7BF31A083E23C60AA" xlink:to="lab_us-gaap_InventoryPolicyTextBlock_B534E7FFAEE059D7BF31A083E23C60AA" xlink:type="arc" />
    <link:label id="lab_us-gaap_DeferredChargesPolicyTextBlock_FFED0AA48AF24A3D253A3CC842909CCB_verboseLabel_en-US" xlink:label="lab_us-gaap_DeferredChargesPolicyTextBlock_F60BA3D139625108AD450F8DA71BA340" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Deferred Contract Costs</link:label>
    <link:label id="lab_us-gaap_DeferredChargesPolicyTextBlock_FFED0AA48AF24A3D253A3CC842909CCB_label_en-US" xlink:label="lab_us-gaap_DeferredChargesPolicyTextBlock_F60BA3D139625108AD450F8DA71BA340" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Charges, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_DeferredChargesPolicyTextBlock" xlink:label="loc_us-gaap_DeferredChargesPolicyTextBlock_F60BA3D139625108AD450F8DA71BA340" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredChargesPolicyTextBlock_F60BA3D139625108AD450F8DA71BA340" xlink:to="lab_us-gaap_DeferredChargesPolicyTextBlock_F60BA3D139625108AD450F8DA71BA340" xlink:type="arc" />
    <link:label id="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_1C409E0FC5170A468B7A3CC842909476_verboseLabel_en-US" xlink:label="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_BDAB21F286015B768D587E5FC73422A9" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Prepaid Expenses and Other Current Assets</link:label>
    <link:label id="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_1C409E0FC5170A468B7A3CC842909476_label_en-US" xlink:label="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_BDAB21F286015B768D587E5FC73422A9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expenses And Other Current Assets (Policy Text Block)</link:label>
    <link:label id="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_1C409E0FC5170A468B7A3CC842909476_documentation_en-US" xlink:label="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_BDAB21F286015B768D587E5FC73422A9" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Prepaid Expenses And Other Current Assets Policy</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock" xlink:label="loc_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_BDAB21F286015B768D587E5FC73422A9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_BDAB21F286015B768D587E5FC73422A9" xlink:to="lab_oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock_BDAB21F286015B768D587E5FC73422A9" xlink:type="arc" />
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_46A4BB6CFC9EFD2A39683CC84290DC60_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_6B96A4F24497555FADCFB9182E976A48" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Property and Equipment</link:label>
    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_46A4BB6CFC9EFD2A39683CC84290DC60_label_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_6B96A4F24497555FADCFB9182E976A48" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Property, Plant and Equipment, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_PropertyPlantAndEquipmentPolicyTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_6B96A4F24497555FADCFB9182E976A48" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_6B96A4F24497555FADCFB9182E976A48" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentPolicyTextBlock_6B96A4F24497555FADCFB9182E976A48" xlink:type="arc" />
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_E36921E0B23E86D020E33CC842900AFD_verboseLabel_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_28C7F6A4C2B35ABB877F398882BAEA92" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other Intangible Assets</link:label>
    <link:label id="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_E36921E0B23E86D020E33CC842900AFD_label_en-US" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_28C7F6A4C2B35ABB877F398882BAEA92" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Goodwill and Intangible Assets, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_28C7F6A4C2B35ABB877F398882BAEA92" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_28C7F6A4C2B35ABB877F398882BAEA92" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsPolicyTextBlock_28C7F6A4C2B35ABB877F398882BAEA92" xlink:type="arc" />
    <link:label id="lab_oesx_OtherLongTermAssetsPolicyTextBlock_6E2559D7F16F63D8438D3CC84290529E_verboseLabel_en-US" xlink:label="lab_oesx_OtherLongTermAssetsPolicyTextBlock_73390E7C314F55F8B8BCF57B16F4DF90" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Other Long-Term Assets</link:label>
    <link:label id="lab_oesx_OtherLongTermAssetsPolicyTextBlock_6E2559D7F16F63D8438D3CC84290529E_label_en-US" xlink:label="lab_oesx_OtherLongTermAssetsPolicyTextBlock_73390E7C314F55F8B8BCF57B16F4DF90" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Long Term Assets [Policy Text Block]</link:label>
    <link:label id="lab_oesx_OtherLongTermAssetsPolicyTextBlock_6E2559D7F16F63D8438D3CC84290529E_documentation_en-US" xlink:label="lab_oesx_OtherLongTermAssetsPolicyTextBlock_73390E7C314F55F8B8BCF57B16F4DF90" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Other Long-Term Assets</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_OtherLongTermAssetsPolicyTextBlock" xlink:label="loc_oesx_OtherLongTermAssetsPolicyTextBlock_73390E7C314F55F8B8BCF57B16F4DF90" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_OtherLongTermAssetsPolicyTextBlock_73390E7C314F55F8B8BCF57B16F4DF90" xlink:to="lab_oesx_OtherLongTermAssetsPolicyTextBlock_73390E7C314F55F8B8BCF57B16F4DF90" xlink:type="arc" />
    <link:label id="lab_oesx_AccruedExpensesPolicyTextBlock_1E8110ADAB82DCF54AA03CC842908BB1_verboseLabel_en-US" xlink:label="lab_oesx_AccruedExpensesPolicyTextBlock_9CB98B09D30D54B9A8DB1B3C8363178F" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accrued Expenses and Other</link:label>
    <link:label id="lab_oesx_AccruedExpensesPolicyTextBlock_1E8110ADAB82DCF54AA03CC842908BB1_label_en-US" xlink:label="lab_oesx_AccruedExpensesPolicyTextBlock_9CB98B09D30D54B9A8DB1B3C8363178F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Expenses [Policy Text Block]</link:label>
    <link:label id="lab_oesx_AccruedExpensesPolicyTextBlock_1E8110ADAB82DCF54AA03CC842908BB1_documentation_en-US" xlink:label="lab_oesx_AccruedExpensesPolicyTextBlock_9CB98B09D30D54B9A8DB1B3C8363178F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accrued Expenses, Policy</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_AccruedExpensesPolicyTextBlock" xlink:label="loc_oesx_AccruedExpensesPolicyTextBlock_9CB98B09D30D54B9A8DB1B3C8363178F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AccruedExpensesPolicyTextBlock_9CB98B09D30D54B9A8DB1B3C8363178F" xlink:to="lab_oesx_AccruedExpensesPolicyTextBlock_9CB98B09D30D54B9A8DB1B3C8363178F" xlink:type="arc" />
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_08EF5910CE783E661C523CC842909073_verboseLabel_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock_C2FF7E92415E5BA7B8E58E4A06D3DBD9" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Revenue Recognition</link:label>
    <link:label id="lab_us-gaap_RevenueRecognitionPolicyTextBlock_08EF5910CE783E661C523CC842909073_label_en-US" xlink:label="lab_us-gaap_RevenueRecognitionPolicyTextBlock_C2FF7E92415E5BA7B8E58E4A06D3DBD9" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revenue Recognition, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_RevenueRecognitionPolicyTextBlock" xlink:label="loc_us-gaap_RevenueRecognitionPolicyTextBlock_C2FF7E92415E5BA7B8E58E4A06D3DBD9" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRecognitionPolicyTextBlock_C2FF7E92415E5BA7B8E58E4A06D3DBD9" xlink:to="lab_us-gaap_RevenueRecognitionPolicyTextBlock_C2FF7E92415E5BA7B8E58E4A06D3DBD9" xlink:type="arc" />
    <link:label id="lab_us-gaap_EarningsPerSharePolicyTextBlock_B6B70DF98D232A7CE1DC3CC84290BA40_verboseLabel_en-US" xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock_2CD273A7CA855D9A968F0A957AAE917F" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Net Loss per Common Share</link:label>
    <link:label id="lab_us-gaap_EarningsPerSharePolicyTextBlock_B6B70DF98D232A7CE1DC3CC84290BA40_label_en-US" xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock_2CD273A7CA855D9A968F0A957AAE917F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_EarningsPerSharePolicyTextBlock" xlink:label="loc_us-gaap_EarningsPerSharePolicyTextBlock_2CD273A7CA855D9A968F0A957AAE917F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerSharePolicyTextBlock_2CD273A7CA855D9A968F0A957AAE917F" xlink:to="lab_us-gaap_EarningsPerSharePolicyTextBlock_2CD273A7CA855D9A968F0A957AAE917F" xlink:type="arc" />
    <link:label id="lab_us-gaap_ConcentrationRiskCreditRisk_CACC258C536B006EDEE33CC84290D2EE_verboseLabel_en-US" xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk_0B3E8B466222540286C2B2FD7939EDDB" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Concentration of Credit Risk and Other Risks and Uncertainties</link:label>
    <link:label id="lab_us-gaap_ConcentrationRiskCreditRisk_CACC258C536B006EDEE33CC84290D2EE_label_en-US" xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk_0B3E8B466222540286C2B2FD7939EDDB" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ConcentrationRiskCreditRisk" xlink:label="loc_us-gaap_ConcentrationRiskCreditRisk_0B3E8B466222540286C2B2FD7939EDDB" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskCreditRisk_0B3E8B466222540286C2B2FD7939EDDB" xlink:to="lab_us-gaap_ConcentrationRiskCreditRisk_0B3E8B466222540286C2B2FD7939EDDB" xlink:type="arc" />
    <link:label id="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_8D033926D3E66104FF7B3CC84290F275_verboseLabel_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_EB1110608998579F91F076B4A6F5A75C" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Recent Accounting Pronouncements</link:label>
    <link:label id="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_8D033926D3E66104FF7B3CC84290F275_label_en-US" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_EB1110608998579F91F076B4A6F5A75C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_EB1110608998579F91F076B4A6F5A75C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_EB1110608998579F91F076B4A6F5A75C" xlink:to="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_EB1110608998579F91F076B4A6F5A75C" xlink:type="arc" />
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2_terseLabel_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant [Roll Forward]</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2_label_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant [Roll Forward]</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2_documentation_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant [Roll Forward]</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward" xlink:label="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2" xlink:to="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward_8428D770FBDD6A0AD39921673403F2B2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Shares Available for Grant, Beginning Balance (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_6E9D52F9D523BDD558DB216734030B97" xlink:type="arc" />
    <link:label id="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_EDF6BC7532F912E175DD2167340431D8_terseLabel_en-US" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_EDF6BC7532F912E175DD2167340431D8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares Available for Grant, Shares Reserved Under New Plan (share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_EDF6BC7532F912E175DD2167340431D8" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_EDF6BC7532F912E175DD2167340431D8" xlink:to="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance_EDF6BC7532F912E175DD2167340431D8" xlink:type="arc" />
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C_negatedLabel_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Shares Available for Grant, Granted to Employee (shares)</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C_label_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Shares Issued to Employee</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C_documentation_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Shares Issued to Employee</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee" xlink:label="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C" xlink:to="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee_D78891E83A1614F96B12216734044F6C" xlink:type="arc" />
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841_negatedTerseLabel_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Shares Available for Grant, Granted to Non-Employee (shares)</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841_label_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Shares Issued to Non-Employee</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841_documentation_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Shares Issued to Non-Employee</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee" xlink:label="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841" xlink:to="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee_BC17FCC0BE6C127D8B85216734047841" xlink:type="arc" />
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170_terseLabel_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares Available for Grant, Forfeited (shares)</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170_label_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Forfeited</link:label>
    <link:label id="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170_documentation_en-US" xlink:label="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Forfeited</link:label>
    <link:loc xlink:href="oesx-20160930.xsd#oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited" xlink:label="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170" xlink:to="lab_oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited_11EB440F5D091E19940E21673404C170" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_3CA0AD155A3FDAF279E421673404D732_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_3CA0AD155A3FDAF279E421673404D732" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Shares Available for Grant, Ending Balance (shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_3CA0AD155A3FDAF279E421673404D732" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_3CA0AD155A3FDAF279E421673404D732" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_3CA0AD155A3FDAF279E421673404D732" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingRollForward_DFF86BB8EA7F42ACD303216734049216" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Number of Shares, Beginning Balance (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_0B03464C73EE71B1A5BF21673404CC17" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_259A6FF3EE5A4686F82E21673404E959_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_259A6FF3EE5A4686F82E21673404E959" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of Shares, Granted (shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_259A6FF3EE5A4686F82E21673404E959" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_259A6FF3EE5A4686F82E21673404E959" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross_259A6FF3EE5A4686F82E21673404E959" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080_negatedLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of Shares, Forfeited (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod_E239A235DCA4F1CA5F4621673404F080" xlink:type="arc" />
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6_negatedLabel_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Number of Shares, Exercised (shares)</link:label>
    <link:label id="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6_label_en-US" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_D4285E84C960B43605EF21673404B2F6" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_A060E30A19BD4A51AA1621673404AA9C_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_A060E30A19BD4A51AA1621673404AA9C" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Number of Shares, Ending Balance (shares)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_A060E30A19BD4A51AA1621673404AA9C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_A060E30A19BD4A51AA1621673404AA9C" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber_A060E30A19BD4A51AA1621673404AA9C" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of Shares, Exercisable (shares)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber_79AE00F7159382F5DB9421673404E01A" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePriceRollforward_ECBE10785011137845BF21673404AC13" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96_periodStartLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price, Beginning Balance (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_35A16BAD8AD689834445216734042F96" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price, Granted Stock Options (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice_C6C546CDF5DC977D46712167340462D2" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price, Forfeited (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice_E37972A22B1C1C8FCE0721673404171E" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0_verboseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price, Exercised (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice_BE31A3C6AC43A9BC8A32216734049EC0" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_3A349925ECFA191D41472167340462F5_periodEndLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_3A349925ECFA191D41472167340462F5" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price, Ending Balance (in dollars per share)</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_3A349925ECFA191D41472167340462F5" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_3A349925ECFA191D41472167340462F5" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice_3A349925ECFA191D41472167340462F5" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Exercise Price, Exercisable Ending Balance (in dollars per share)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice_29C623B4237B0EC4587A216734046FE4" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Remaining Contractual Term (in years)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2_3E30C11586D1C8830604216734049278" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954_terseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Remaining Contractual Term, Exercisable (in years)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1_46AA63A773ACE6C1FE0E216734041954" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Aggregate Intrinsic Value, Ending Balance (in dollars)</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue_EFFE7E71A0E3CAF79508216734045799" xlink:type="arc" />
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824_verboseLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Aggregate Intrinsic Value, Exercisable (in dollars)</link:label>
    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2016/elts/us-gaap-2016-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1_9A428357C159B80CE734216734045824" xlink:type="arc" />
  </link:labelLink>
</link:linkbase>





