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    <link:label id="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_D662E03B8E7897DC2472D874D6AB3633_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionDescriptionAxis_D662E03B8E7897DC2472D874D6AB3633" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Description [Axis]</link:label>
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    <link:label id="lab_us-gaap_SaleLeasebackTransactionNameDomain_FF6AE48359FBACC3B6A5D874D6AB05E2_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionNameDomain_FF6AE48359FBACC3B6A5D874D6AB05E2" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Name [Domain]</link:label>
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    <link:label id="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_ACA991115CB07B014220D874D6AC8910_terseLabel_en-US" xlink:label="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_ACA991115CB07B014220D874D6AC8910" 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_ACA991115CB07B014220D874D6AC8910_label_en-US" xlink:label="lab_oesx_AgreementwithTramontinaU.S.CookwareInc.Member_ACA991115CB07B014220D874D6AC8910" 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>
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    <link:label id="lab_us-gaap_ProductsAndServicesDomain_DD59ED8DAC61028F26CAD874D6ACF5B3_terseLabel_en-US" xlink:label="lab_us-gaap_ProductsAndServicesDomain_DD59ED8DAC61028F26CAD874D6ACF5B3" 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_DD59ED8DAC61028F26CAD874D6ACF5B3_label_en-US" xlink:label="lab_us-gaap_ProductsAndServicesDomain_DD59ED8DAC61028F26CAD874D6ACF5B3" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Products and Services [Domain]</link:label>
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    <link:label id="lab_oesx_HighIntensityFluorescentLightingProductsMember_0B8F4304BF5C131BBDA3D874D6AC4A1B_terseLabel_en-US" xlink:label="lab_oesx_HighIntensityFluorescentLightingProductsMember_0B8F4304BF5C131BBDA3D874D6AC4A1B" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">High Intensity Fluorescent Lighting Products</link:label>
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    <link:loc xlink:href="oesx-20161231.xsd#oesx_HighIntensityFluorescentLightingProductsMember" xlink:label="loc_oesx_HighIntensityFluorescentLightingProductsMember_0B8F4304BF5C131BBDA3D874D6AC4A1B" xlink:type="locator" />
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    <link:label id="lab_oesx_AccountsReceivablesDueMinimumPeriod_29E38A1C155BAAD2E720D874D6AC281E_verboseLabel_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMinimumPeriod_29E38A1C155BAAD2E720D874D6AC281E" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Accounts receivable are due, minimum period</link:label>
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    <link:label id="lab_oesx_AccountsReceivablesDueMaximumPeriod_53DD01633A0D7FAC7FDFD874D6AC65D6_documentation_en-US" xlink:label="lab_oesx_AccountsReceivablesDueMaximumPeriod_53DD01633A0D7FAC7FDFD874D6AC65D6" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Accounts receivables due maximum period.</link:label>
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    <link:label id="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_F6665B7AFF85167B9B74D874D6ACA619_terseLabel_en-US" xlink:label="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_F6665B7AFF85167B9B74D874D6ACA619" 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</link:label>
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    <link:label id="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_F6665B7AFF85167B9B74D874D6ACA619_documentation_en-US" xlink:label="lab_oesx_InventoryReserveLengthofTimeofInventoryUsageConsidered_F6665B7AFF85167B9B74D874D6ACA619" 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>
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    <link:label id="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_EFF281405E49EF54651AD874D6AC48BE_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionNetProceedsInvestingActivities_EFF281405E49EF54651AD874D6AC48BE" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash purchase price of sale leaseback</link:label>
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    <link:label id="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_81B4F7913BB7397F6550D874D6AC4661_terseLabel_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionAreaofLeasedProperty_81B4F7913BB7397F6550D874D6AC4661" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Area of leased building (sq ft)</link:label>
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    <link:label id="lab_oesx_SaleLeasebackTransactionLeaseTerm_312DD86CE493E24311F0D874D6ACD033_terseLabel_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionLeaseTerm_312DD86CE493E24311F0D874D6ACD033" 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_312DD86CE493E24311F0D874D6ACD033_label_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionLeaseTerm_312DD86CE493E24311F0D874D6ACD033" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale Leaseback Transaction, Lease Term</link:label>
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    <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_0DE15EE6439FAF778741D874D5DD1E00" xlink:type="locator" />
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    <link:label id="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_74F63CB3F6E6D2CBF58CD874D5DD5F7D_negatedLabel_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_74F63CB3F6E6D2CBF58CD874D5DD5F7D" 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_74F63CB3F6E6D2CBF58CD874D5DD5F7D_label_en-US" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares_74F63CB3F6E6D2CBF58CD874D5DD5F7D" 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>
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    <link:label id="lab_us-gaap_LandImprovementsMember_4E90579F3D4E27C87EB1B7F33D92A1D8_terseLabel_en-US" xlink:label="lab_us-gaap_LandImprovementsMember_4E90579F3D4E27C87EB1B7F33D92A1D8" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Land and land improvements</link:label>
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    <link:label id="lab_us-gaap_BuildingAndBuildingImprovementsMember_FD5B79E3213BD8215085B7F33D92B47D_verboseLabel_en-US" xlink:label="lab_us-gaap_BuildingAndBuildingImprovementsMember_FD5B79E3213BD8215085B7F33D92B47D" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" 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_FD5B79E3213BD8215085B7F33D92B47D" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LeaseholdImprovementsMember_C752DF15F72CD74DC6A2B7F33D92EA1A_verboseLabel_en-US" xlink:label="lab_us-gaap_LeaseholdImprovementsMember_C752DF15F72CD74DC6A2B7F33D92EA1A" 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_C752DF15F72CD74DC6A2B7F33D92EA1A_label_en-US" xlink:label="lab_us-gaap_LeaseholdImprovementsMember_C752DF15F72CD74DC6A2B7F33D92EA1A" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Leasehold Improvements [Member]</link:label>
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    <link:label id="lab_us-gaap_EquipmentLeasedToOtherPartyMember_1051716B90F4055E2595B7F33D92FE18_verboseLabel_en-US" xlink:label="lab_us-gaap_EquipmentLeasedToOtherPartyMember_1051716B90F4055E2595B7F33D92FE18" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Equipment leased to customers</link:label>
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    <link:label id="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_766AB401F2A82A1A6BE8B7F33D92E8CF_verboseLabel_en-US" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentOtherTypesMember_766AB401F2A82A1A6BE8B7F33D92E8CF" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Plant equipment</link:label>
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    <link:label id="lab_us-gaap_ConstructionInProgressMember_650BFC41BC9A911F95B1B7F33D92920B_verboseLabel_en-US" xlink:label="lab_us-gaap_ConstructionInProgressMember_650BFC41BC9A911F95B1B7F33D92920B" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Construction in progress</link:label>
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    <link:label id="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_AC1C2F83C1B5A283A76C3CC842003525_terseLabel_en-US" xlink:label="lab_us-gaap_AssetsHeldUnderCapitalLeasesMember_0DCAE51331B85ACB8A180782621E700A" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets Held under Capital Leases</link:label>
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    <link:label id="lab_oesx_InventoryFinishedGoodsValuationReserves_312E1F4C7F54BF2AE48A3D35EDBA01F8_negatedTerseLabel_en-US" xlink:label="lab_oesx_InventoryFinishedGoodsValuationReserves_8EF05BFBC6C5581586A5CA20128CF27D" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Finished goods, obsolescence reserve</link:label>
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    <link:label id="lab_us-gaap_InventoryNet_57039B238CDECB33DDA73CC8421F33EC_totalLabel_en-US" xlink:label="lab_us-gaap_InventoryNet_982810AE0D1E53B7BE014055101C303E" 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_982810AE0D1E53B7BE014055101C303E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Inventory, Net</link:label>
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    <link:label id="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_BC5954B0F9882FBB3DCED874D6BEE47F_terseLabel_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_BC5954B0F9882FBB3DCED874D6BEE47F" 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_BC5954B0F9882FBB3DCED874D6BEE47F_label_en-US" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract_BC5954B0F9882FBB3DCED874D6BEE47F" 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>
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    <link:label id="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_3043A1B90F25493C0E0FD874D6BE9E83_verboseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_3043A1B90F25493C0E0FD874D6BE9E83" 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_3043A1B90F25493C0E0FD874D6BE9E83_label_en-US" xlink:label="lab_us-gaap_AdjustmentsNoncashItemsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_3043A1B90F25493C0E0FD874D6BE9E83" 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>
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    <link:label id="lab_us-gaap_AdjustmentForAmortization_315AE11E2F26101ED651D874D6BF7DF7_terseLabel_en-US" xlink:label="lab_us-gaap_AdjustmentForAmortization_315AE11E2F26101ED651D874D6BF7DF7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Amortization</link:label>
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    <link:label id="lab_us-gaap_ShareBasedCompensation_F0FFF5AA4D3159B2B6B4D874D6BFA9BC_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensation_F0FFF5AA4D3159B2B6B4D874D6BFA9BC" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation</link:label>
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    <link:label id="lab_us-gaap_LineOfCreditFacilityLineItems_B24A519C86E75C43AFCE1AD51D42A5F5_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityLineItems_B24A519C86E75C43AFCE1AD51D42A5F5" 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_B24A519C86E75C43AFCE1AD51D42A5F5" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_A102A615A82EF959003B1AD51D42235B_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_A102A615A82EF959003B1AD51D42235B" 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_A102A615A82EF959003B1AD51D42235B_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity_A102A615A82EF959003B1AD51D42235B" 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_A102A615A82EF959003B1AD51D42235B" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_5A0419FC64E40124CA211AD51D4217A2_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_5A0419FC64E40124CA211AD51D4217A2" 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_5A0419FC64E40124CA211AD51D4217A2_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_5A0419FC64E40124CA211AD51D4217A2" 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_5A0419FC64E40124CA211AD51D4217A2" xlink:type="locator" />
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    <link:label id="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_EFE19F5CE5EE6E9FFF9A1AD51D4280A8_terseLabel_en-US" xlink:label="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_EFE19F5CE5EE6E9FFF9A1AD51D4280A8" 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_EFE19F5CE5EE6E9FFF9A1AD51D4280A8_label_en-US" xlink:label="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_EFE19F5CE5EE6E9FFF9A1AD51D4280A8" 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_EFE19F5CE5EE6E9FFF9A1AD51D4280A8_documentation_en-US" xlink:label="lab_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_EFE19F5CE5EE6E9FFF9A1AD51D4280A8" 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-20161231.xsd#oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity" xlink:label="loc_oesx_LineofCreditFacilityPotentialMaximumBorrowingCapacity_EFE19F5CE5EE6E9FFF9A1AD51D4280A8" xlink:type="locator" />
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    <link:label id="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_8B02E0FECD6CAF2B2C3D1AD51D43D68E_terseLabel_en-US" xlink:label="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_8B02E0FECD6CAF2B2C3D1AD51D43D68E" 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_8B02E0FECD6CAF2B2C3D1AD51D43D68E_label_en-US" xlink:label="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_8B02E0FECD6CAF2B2C3D1AD51D43D68E" 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_8B02E0FECD6CAF2B2C3D1AD51D43D68E_documentation_en-US" xlink:label="lab_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_8B02E0FECD6CAF2B2C3D1AD51D43D68E" 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-20161231.xsd#oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio" xlink:label="loc_oesx_LineofCreditFacilityCovenantTermsMinimumIndebtednessRatio_8B02E0FECD6CAF2B2C3D1AD51D43D68E" xlink:type="locator" />
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    <link:label id="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0696D5483FC9B0A329F81AD51D43F186_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0696D5483FC9B0A329F81AD51D43F186" 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_0696D5483FC9B0A329F81AD51D43F186_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1_0696D5483FC9B0A329F81AD51D43F186" 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_0696D5483FC9B0A329F81AD51D43F186" xlink:type="locator" />
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    <link:label id="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_EC6833710E94C451CBB21AD51D43DB78_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_EC6833710E94C451CBB21AD51D43DB78" 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_EC6833710E94C451CBB21AD51D43DB78_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentPeriodicPaymentInterest_EC6833710E94C451CBB21AD51D43DB78" 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_EC6833710E94C451CBB21AD51D43DB78" xlink:type="locator" />
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    <link:label id="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_3993D5DEE1B3149437EB1AD51D43D3DA_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_3993D5DEE1B3149437EB1AD51D43D3DA" 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_3993D5DEE1B3149437EB1AD51D43D3DA_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentInterestRateEffectivePercentage_3993D5DEE1B3149437EB1AD51D43D3DA" 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_3993D5DEE1B3149437EB1AD51D43D3DA" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_DA99CB746430E3BE87221AD51D430598_terseLabel_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_DA99CB746430E3BE87221AD51D430598" 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_DA99CB746430E3BE87221AD51D430598_label_en-US" xlink:label="lab_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_DA99CB746430E3BE87221AD51D430598" 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_DA99CB746430E3BE87221AD51D430598" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LettersOfCreditOutstandingAmount_969709BDDAD79D0F26D31AD51D438735_terseLabel_en-US" xlink:label="lab_us-gaap_LettersOfCreditOutstandingAmount_969709BDDAD79D0F26D31AD51D438735" 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_969709BDDAD79D0F26D31AD51D438735_label_en-US" xlink:label="lab_us-gaap_LettersOfCreditOutstandingAmount_969709BDDAD79D0F26D31AD51D438735" 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_969709BDDAD79D0F26D31AD51D438735" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LongTermLineOfCredit_14EE9F07AA81B9DD613F1AD51D43766D_terseLabel_en-US" xlink:label="lab_us-gaap_LongTermLineOfCredit_14EE9F07AA81B9DD613F1AD51D43766D" 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_14EE9F07AA81B9DD613F1AD51D43766D_label_en-US" xlink:label="lab_us-gaap_LongTermLineOfCredit_14EE9F07AA81B9DD613F1AD51D43766D" 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_14EE9F07AA81B9DD613F1AD51D43766D" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermLineOfCredit_14EE9F07AA81B9DD613F1AD51D43766D" xlink:to="lab_us-gaap_LongTermLineOfCredit_14EE9F07AA81B9DD613F1AD51D43766D" xlink:type="arc" />
    <link:label id="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64_terseLabel_en-US" xlink:label="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64" 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_899A4179155D264B768C1AD51D439F64_label_en-US" xlink:label="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64" 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_899A4179155D264B768C1AD51D439F64_documentation_en-US" xlink:label="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64" 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-20161231.xsd#oesx_LineofCreditFacilityAdditionalBorrowingCapacity" xlink:label="loc_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64" xlink:to="lab_oesx_LineofCreditFacilityAdditionalBorrowingCapacity_899A4179155D264B768C1AD51D439F64" xlink:type="arc" />
    <link:label id="lab_us-gaap_DebtInstrumentFaceAmount_9E386850EFA4F7808EC51AD51D432502_terseLabel_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount_9E386850EFA4F7808EC51AD51D432502" 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_9E386850EFA4F7808EC51AD51D432502_label_en-US" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount_9E386850EFA4F7808EC51AD51D432502" 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_9E386850EFA4F7808EC51AD51D432502" xlink:type="locator" />
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    <link:label id="lab_oesx_NotPastDueMember_306264077EFDAE03194F3CC8423668F6_label_en-US" xlink:label="lab_oesx_NotPastDueMember_87FAFC20619153BB824D2CE13C643711" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Not Past Due [Member]</link:label>
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    <link:loc xlink:href="oesx-20161231.xsd#oesx_EngineeredSystemsMember" xlink:label="loc_oesx_EngineeredSystemsMember_0B8028B5E50812285220D874D5CF609F" xlink:type="locator" />
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    <link:loc xlink:href="oesx-20161231.xsd#oesx_DistributionServicesMember" xlink:label="loc_oesx_DistributionServicesMember_7E893DD2D27DC0B92205D874D5CFE68E" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_8E297D833B40614E643AD874D63B132C_terseLabel_en-US" xlink:label="lab_us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_8E297D833B40614E643AD874D63B132C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Renewal term of operating lease</link:label>
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    <link:label id="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_DC4BD8C35CF9EA12DBDAD874D63BBCC6_terseLabel_en-US" xlink:label="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_DC4BD8C35CF9EA12DBDAD874D63BBCC6" 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_DC4BD8C35CF9EA12DBDAD874D63BBCC6_label_en-US" xlink:label="lab_oesx_OperatingLeasesMonthlyRentalPaymentsReceivable_DC4BD8C35CF9EA12DBDAD874D63BBCC6" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Leases, Monthly Rental Payments Receivable</link:label>
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    <link:label id="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_D558C83187664AF82BCBD874D63B31A0_terseLabel_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_D558C83187664AF82BCBD874D63B31A0" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Rent expense per square feet</link:label>
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    <link:label id="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_D558C83187664AF82BCBD874D63B31A0_documentation_en-US" xlink:label="lab_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_D558C83187664AF82BCBD874D63B31A0" 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-20161231.xsd#oesx_SaleLeasebackTransactionRentExpensePerSquareFoot" xlink:label="loc_oesx_SaleLeasebackTransactionRentExpensePerSquareFoot_D558C83187664AF82BCBD874D63B31A0" xlink:type="locator" />
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    <link:label id="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_1246D299C4508FF0059CD874D63B6FB0_terseLabel_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_1246D299C4508FF0059CD874D63B6FB0" 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_1246D299C4508FF0059CD874D63B6FB0_label_en-US" xlink:label="lab_us-gaap_SaleLeasebackTransactionMonthlyRentalPayments_1246D299C4508FF0059CD874D63B6FB0" 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_1246D299C4508FF0059CD874D63B6FB0" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LossContingencyClaimsDismissedNumber_A1362B2C14A05F591895D874D63CB414_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingencyClaimsDismissedNumber_A1362B2C14A05F591895D874D63CB414" 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_A1362B2C14A05F591895D874D63CB414_label_en-US" xlink:label="lab_us-gaap_LossContingencyClaimsDismissedNumber_A1362B2C14A05F591895D874D63CB414" 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_A1362B2C14A05F591895D874D63CB414" xlink:type="locator" />
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    <link:label id="lab_us-gaap_LitigationSettlementAmount_EC1D474D027F3A486E53D874D63C1EC7_negatedTerseLabel_en-US" xlink:label="lab_us-gaap_LitigationSettlementAmount_EC1D474D027F3A486E53D874D63C1EC7" 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_EC1D474D027F3A486E53D874D63C1EC7_label_en-US" xlink:label="lab_us-gaap_LitigationSettlementAmount_EC1D474D027F3A486E53D874D63C1EC7" 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_EC1D474D027F3A486E53D874D63C1EC7" xlink:type="locator" />
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    <link:label id="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_B1D43F355DF9CC545EA43D577D263105_terseLabel_en-US" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent_D314A1612A6258008E6AB57100D38455" 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_D314A1612A6258008E6AB57100D38455" 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_D314A1612A6258008E6AB57100D38455" xlink:type="locator" />
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    <link:label id="lab_us-gaap_SalesAndExciseTaxPayableCurrent_9657A7ABCF94F281E4E73D57817F7B11_terseLabel_en-US" xlink:label="lab_us-gaap_SalesAndExciseTaxPayableCurrent_1D911EF9FA5D590E86DC21D5BF400FDB" 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_1D911EF9FA5D590E86DC21D5BF400FDB" 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_1D911EF9FA5D590E86DC21D5BF400FDB" xlink:type="locator" />
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    <link:label id="lab_oesx_AccruedContractCostsCurrent_FDCB55C89B4CC5916C8B3D578604C0B7_terseLabel_en-US" xlink:label="lab_oesx_AccruedContractCostsCurrent_798716040A705C6C81DB5B720C47842C" 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_798716040A705C6C81DB5B720C47842C" 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_798716040A705C6C81DB5B720C47842C" 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-20161231.xsd#oesx_AccruedContractCostsCurrent" xlink:label="loc_oesx_AccruedContractCostsCurrent_798716040A705C6C81DB5B720C47842C" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_oesx_AccruedContractCostsCurrent_798716040A705C6C81DB5B720C47842C" xlink:to="lab_oesx_AccruedContractCostsCurrent_798716040A705C6C81DB5B720C47842C" xlink:type="arc" />
    <link:label id="lab_us-gaap_AccruedProfessionalFeesCurrent_EBBD98984AF5AFA2BB2C3D578ACBB555_terseLabel_en-US" xlink:label="lab_us-gaap_AccruedProfessionalFeesCurrent_B5C842BA73B1584EAE0694051F454D98" 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_B5C842BA73B1584EAE0694051F454D98" 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_B5C842BA73B1584EAE0694051F454D98" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedProfessionalFeesCurrent_B5C842BA73B1584EAE0694051F454D98" xlink:to="lab_us-gaap_AccruedProfessionalFeesCurrent_B5C842BA73B1584EAE0694051F454D98" xlink:type="arc" />
    <link:label id="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_AFE8F459AC0F4E0784473D578FA42CE1_terseLabel_en-US" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent_A44F99DBE1FB5E959FCE5F607613EAF9" 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_A44F99DBE1FB5E959FCE5F607613EAF9" 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_A44F99DBE1FB5E959FCE5F607613EAF9" xlink:type="locator" />
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    <link:label id="lab_us-gaap_OtherAccruedLiabilitiesCurrent_8160DE16D4DFE2E613CF3D57948795F7_terseLabel_en-US" xlink:label="lab_us-gaap_OtherAccruedLiabilitiesCurrent_9613F6517A3C52E29F4F79A5FFAC2193" 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_9613F6517A3C52E29F4F79A5FFAC2193" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Other Accrued Liabilities, Current</link:label>
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    <link:label id="lab_us-gaap_AccruedLiabilitiesCurrent_B1D75789BAA43AF9AD2B3D57993A7DF6_totalLabel_en-US" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent_B7995290905156F3A0C21897D56912C5" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
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    <link:label id="lab_us-gaap_LossContingencyAccrualAtCarryingValue_AE51B2ECE67A99287F403D5971AF91CF_terseLabel_en-US" xlink:label="lab_us-gaap_LossContingencyAccrualAtCarryingValue_95BBC7869B485B25ABF2FEF0808AE3F2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Loss contingency</link:label>
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    <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_95BBC7869B485B25ABF2FEF0808AE3F2" xlink:type="locator" />
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