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  <xs:import namespace="http://fasb.org/us-types/2014-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2014/elts/us-types-2014-01-31.xsd"/>
  <xs:import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd"/>
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  <xs:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
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  <xs:element name="ForeignExchangeGainLossAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_ForeignExchangeGainLossAbstract"/>
  <xs:element name="ForeignCurrencyDenominatedCertificatesOfDepositAndCashAccountsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_ForeignCurrencyDenominatedCertificatesOfDepositAndCashAccountsAbstract"/>
  <xs:element name="RevenuesByMajorCustomersAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_RevenuesByMajorCustomersAbstract"/>
  <xs:element name="MarketableSecuritiesThatMatureWithinOneYearAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_MarketableSecuritiesThatMatureWithinOneYearAbstract"/>
  <xs:element name="BalanceSheetDetailAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_BalanceSheetDetailAbstract"/>
  <xs:element name="CustomerAdvancesAndDepositsDisclosureTextBlockAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_CustomerAdvancesAndDepositsDisclosureTextBlockAbstract"/>
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  <xs:element name="OceanPowerTechnologiesIncStockholdersEquityAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_OceanPowerTechnologiesIncStockholdersEquityAbstract"/>
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  <xs:element name="CashFlowsFromInvestingActivitiesAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_CashFlowsFromInvestingActivitiesAbstract"/>
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  <xs:element name="RelatedPartyTransactionTermOfAgreement" type="xbrli:durationItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_RelatedPartyTransactionTermOfAgreement"/>
  <xs:element name="RelatedPartyTransactionMonthlyConsultingFee" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item" id="optt_RelatedPartyTransactionMonthlyConsultingFee"/>
  <xs:element name="RelatedPartyTransactionDailyConsultingFee" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item" id="optt_RelatedPartyTransactionDailyConsultingFee"/>
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  <xs:element name="DeferredCreditsPayableMarketDiscountRate" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item" id="optt_DeferredCreditsPayableMarketDiscountRate"/>
  <xs:element name="DeferredCreditsPayableMarketLiquidatedDamagesRate" type="num:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" substitutionGroup="xbrli:item" id="optt_DeferredCreditsPayableMarketLiquidatedDamagesRate"/>
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  <xs:element name="ProposedCostOfBuilding" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" nillable="true" substitutionGroup="xbrli:item" id="optt_ProposedCostOfBuilding"/>
  <xs:element name="ATMFacilityMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_ATMFacilityMember"/>
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  <xs:element name="AustralianRenewableEnergyAgencyMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_AustralianRenewableEnergyAgencyMember"/>
  <xs:element name="BarclaysBankAgreementMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_BarclaysBankAgreementMember"/>
  <xs:element name="BarclaysBankMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_BarclaysBankMember"/>
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  <xs:element name="EuropeanUnionWaverPortProjectMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_EuropeanUnionWaverPortProjectMember"/>
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  <xs:element name="FormerExecutiveViceChairmanMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_FormerExecutiveViceChairmanMember"/>
  <xs:element name="GrantFundingMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_GrantFundingMember"/>
  <xs:element name="IbermarMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_IbermarMember"/>
  <xs:element name="IncludingNon-employeeCompensationMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_IncludingNon-employeeCompensationMember"/>
  <xs:element name="InterimChiefExecutiveOfficerMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_InterimChiefExecutiveOfficerMember"/>
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  <xs:element name="MitsuiEngineeringAndShipBuildingMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_MitsuiEngineeringAndShipBuildingMember"/>
  <xs:element name="NJBPUAgreementMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_NJBPUAgreementMember"/>
  <xs:element name="NewJerseyBoardofPublicUtilitiesMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_NewJerseyBoardofPublicUtilitiesMember"/>
  <xs:element name="NonEmployeeDirectorsMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_NonEmployeeDirectorsMember"/>
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  <xs:element name="ShortTermMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_ShortTermMember"/>
  <xs:element name="SpanishTaxAuthoritiesMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_SpanishTaxAuthoritiesMember"/>
  <xs:element name="StockIncentivePlan2006Member" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_StockIncentivePlan2006Member"/>
  <xs:element name="StockPlan2001Member" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_StockPlan2001Member"/>
  <xs:element name="ThreeLettersOfCreditMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_ThreeLettersOfCreditMember"/>
  <xs:element name="UKGovernmentsTechnologyStrategyBoardMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_UKGovernmentsTechnologyStrategyBoardMember"/>
  <xs:element name="USDepartmentofEnergyMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_USDepartmentofEnergyMember"/>
  <xs:element name="USTreasuryobligationsMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_USTreasuryobligationsMember"/>
  <xs:element name="UnderwritingAgreementMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_UnderwritingAgreementMember"/>
  <xs:element name="UnrestrictedMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_UnrestrictedMember"/>
  <xs:element name="UponTerminationAgreementMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_UponTerminationAgreementMember"/>
  <xs:element name="VictorianWavePartnersPtyLtdMember" type="nonnum:domainItemType" abstract="false" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_VictorianWavePartnersPtyLtdMember"/>
  <xs:element name="DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" substitutionGroup="xbrli:item" id="optt_DocumentAndEntityInformationAbstract"/>
</xs:schema>
