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  <xsd:element abstract="true" id="oesx_LondonInterbankOfferedRateLiborMember" name="LondonInterbankOfferedRateLiborMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_LongTermInventoriesPolicyTextBlock" name="LongTermInventoriesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_LongTermReceivablesPolicyTextBlock" name="LongTermReceivablesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_LongTermReceivablesPresentValueOfFutureCashFlowsDiscountedRateMaximum" name="LongTermReceivablesPresentValueOfFutureCashFlowsDiscountedRateMaximum" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_LongTermReceivablesPresentValueOfFutureCashFlowsDiscountedRateMinimum" name="LongTermReceivablesPresentValueOfFutureCashFlowsDiscountedRateMinimum" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_MaximumAmountLimitForEmployeeStockPurchasePlanPerEmployee" name="MaximumAmountLimitForEmployeeStockPurchasePlanPerEmployee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="oesx_MinimumSubscriptionPercentage" name="MinimumSubscriptionPercentage" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_NameofMajorSupplierDomain" name="NameofMajorSupplierDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_NonEmployeeDirectorMember" name="NonEmployeeDirectorMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_NoncashOrPartNoncashAcquisitionNoncashContingentConsiderationLiability" name="NoncashOrPartNoncashAcquisitionNoncashContingentConsiderationLiability" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="oesx_NoncashOrPartNoncashAcquisitionNoncashFinancialOrEquityInstrumentConsiderationIssued" name="NoncashOrPartNoncashAcquisitionNoncashFinancialOrEquityInstrumentConsiderationIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_NotPastDueMember" name="NotPastDueMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_October2011Member" name="October2011Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_OneToNinetyDaysMember" name="OneToNinetyDaysMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions" name="OperatingLossCarryforwardsAssociatedWithExerciseOfNonQualifiedStockOptions" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="oesx_OtherLongTermAssetsPolicyTextBlock" name="OtherLongTermAssetsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_OtherLongTermDebtMember" name="OtherLongTermDebtMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_PastDueLeaseNetMember" name="PastDueLeaseNetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_PowerPurchaseAgreementProductRevenueRecognizableTerm" name="PowerPurchaseAgreementProductRevenueRecognizableTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock" name="PrepaidExpensesAndOtherCurrentAssetsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_PropertyPlantAndEquipmentEstimatedUsefulLife" name="PropertyPlantAndEquipmentEstimatedUsefulLife" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ReclassificationsPolicyTextBlock" name="ReclassificationsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_RestrictedSharesIssuedToKeyEmployeesAbstract" name="RestrictedSharesIssuedToKeyEmployeesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_RightIssueSharePrice" name="RightIssueSharePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="oesx_RightsDistributionDateTriggerNumberOfBusinessDaysAfterCommencementOrOfferOfAcquisition" name="RightsDistributionDateTriggerNumberOfBusinessDaysAfterCommencementOrOfferOfAcquisition" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_SalesTypeNetMember" name="SalesTypeNetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_ScheduleOfWarrants" name="ScheduleOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeitureRate" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedForfeitureRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantForfeited" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantRollForward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToEmployee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrantSharesIssuedToNonEmployee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedNumberOfShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedNumberOfShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedNumberOfSharesRollForward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonvestedOptionsForfeitedNumberOfShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedNumberOfShares" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedNumberOfShares" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_ShareBasedCompensationArrangementFairValueAssumptionsExpectedShareBasedPaymentAbstract" name="ShareBasedCompensationArrangementFairValueAssumptionsExpectedShareBasedPaymentAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_ShareBasedCompensationArrangementsByShareBasedPaymentsAwardOptionMaximumLife" name="ShareBasedCompensationArrangementsByShareBasedPaymentsAwardOptionMaximumLife" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_SharePurchaseRightsRedemptionPrice" name="SharePurchaseRightsRedemptionPrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="oesx_SharebasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice" name="SharebasedCompensationArrangementByShareBasedPaymentAwardPerSharePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_SharebasedGoodsandNonemployeeServicesTransactionSecuritiesIssuedValuationPricePerShare" name="SharebasedGoodsandNonemployeeServicesTransactionSecuritiesIssuedValuationPricePerShare" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="oesx_SolarPowerSystemsCompletionPeriodMaximum" name="SolarPowerSystemsCompletionPeriodMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_SolarPowerSystemsCompletionPeriodMinimum" name="SolarPowerSystemsCompletionPeriodMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_StockOptionsRestrictedSharesAndWarrantsTextualAbstract" name="StockOptionsRestrictedSharesAndWarrantsTextualAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="oesx_StockRepurchaseProgramIncreaseInAuthorizedRepurchaseAmount" name="StockRepurchaseProgramIncreaseInAuthorizedRepurchaseAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_SummaryOfIssuanceOfStockUnderEmployeeStockOwnershipPlanAbstract" name="SummaryOfIssuanceOfStockUnderEmployeeStockOwnershipPlanAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_SupplierOneMember" name="SupplierOneMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_SupplierTwoMember" name="SupplierTwoMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_TrademarksandTradeNamesMember" name="TrademarksandTradeNamesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_TwoThousandFourStockAndIncentiveAndAwardPlanMember" name="TwoThousandFourStockAndIncentiveAndAwardPlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_TwoThousandThreeStockOptionMember" name="TwoThousandThreeStockOptionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_VariableRateAxis" name="VariableRateAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="oesx_VariableRateDomain" name="VariableRateDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>





