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  <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_SummaryOfIssuanceOfStockUnderEmployeeStockOwnershipPlanAbstract" name="SummaryOfIssuanceOfStockUnderEmployeeStockOwnershipPlanAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" 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_WellsFargoBankNationalAssociationMember" name="WellsFargoBankNationalAssociationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>





