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  <xs:element id="next_InvestingActivitiesOtherNoncurrentAssets" abstract="false" name="InvestingActivitiesOtherNoncurrentAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_CostsAssociatedWithRepaymentsOfDebt" abstract="false" name="CostsAssociatedWithRepaymentsOfDebt" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" abstract="false" name="ScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:textBlockItemType"/>
  <xs:element id="next_RioGrandeLiquefiedNaturalGasFacilityMember" abstract="true" name="RioGrandeLiquefiedNaturalGasFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="next_NumberOfLiquefactionTrainsAuthorized" abstract="false" name="NumberOfLiquefactionTrainsAuthorized" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="next_LiquefiedNaturalGasExportAuthorizedMass" abstract="false" name="LiquefiedNaturalGasExportAuthorizedMass" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:massItemType"/>
  <xs:element id="next_NumberOfLiquefactionTrains" abstract="false" name="NumberOfLiquefactionTrains" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="next_NumberOfLiquefactionTrainsUnderDevelopment" abstract="false" name="NumberOfLiquefactionTrainsUnderDevelopment" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="next_DerivativeNotionalAmountIncreaseDecrease" abstract="false" name="DerivativeNotionalAmountIncreaseDecrease" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_RioGrandeMember" abstract="true" name="RioGrandeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_LesseeOperatingLeaseNumberOfConsecutiveRenewalTerm" abstract="false" name="LesseeOperatingLeaseNumberOfConsecutiveRenewalTerm" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="next_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_BusinessAcquisitionDeferredTransactionCostsCurrent" abstract="false" name="BusinessAcquisitionDeferredTransactionCostsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_SeniorSecuredNotesMember" abstract="true" name="SeniorSecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_SeniorSecuredLoansMember" abstract="true" name="SeniorSecuredLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_SeniorSecuredNotesAndLoansMember" abstract="true" name="SeniorSecuredNotesAndLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_CdSeniorWorkingCapitalFacilityMember" abstract="true" name="CdSeniorWorkingCapitalFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_CdCreditFacilityMember" abstract="true" name="CdCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_TcfCreditFacilityMember" abstract="true" name="TcfCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_CorporateCreditFacilityMember" abstract="true" name="CorporateCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="next_A6.72SeniorSecuredLoansMember" abstract="true" name="A6.72SeniorSecuredLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="next_A7.11SeniorSecuredLoansMember" abstract="true" name="A7.11SeniorSecuredLoansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="next_A6.85SeniorSecuredNotesMember" abstract="true" name="A6.85SeniorSecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="next_A6.58SeniorSecuredNotesMember" abstract="true" name="A6.58SeniorSecuredNotesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="next_CdCreditFacilityAndTcfCreditFacilityMember" abstract="true" name="CdCreditFacilityAndTcfCreditFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_DebtInstrumentTermThresholdPastLiquefactionTrainFinalInvestmentDecision" abstract="false" name="DebtInstrumentTermThresholdPastLiquefactionTrainFinalInvestmentDecision" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="next_DebtInstrumentCovenantMinimumPercentageOfProjectedPrincipalAmountOutstandingBeHedged" abstract="false" name="DebtInstrumentCovenantMinimumPercentageOfProjectedPrincipalAmountOutstandingBeHedged" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="next_DebtInstrumentCovenantHistoricalDebtServiceCoverageRatioMinimum" abstract="false" name="DebtInstrumentCovenantHistoricalDebtServiceCoverageRatioMinimum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="next_DebtInstrumentCovenantRepurchasePricePercentage" abstract="false" name="DebtInstrumentCovenantRepurchasePricePercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="next_LongTermDebtMaturityRemainderOfFiscalYearAndYearOne" abstract="false" name="LongTermDebtMaturityRemainderOfFiscalYearAndYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_UnvestedStockMember" abstract="true" name="UnvestedStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_CommonStockWarrantsMember" abstract="true" name="CommonStockWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="next_AccountsPayableAcquisitionOfPropertyPlantAndEquipment" abstract="false" name="AccountsPayableAcquisitionOfPropertyPlantAndEquipment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_AccruedLiabilitiesAcquisitionOfPropertyPlantAndEquipment" abstract="false" name="AccruedLiabilitiesAcquisitionOfPropertyPlantAndEquipment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_NoncashOrPartNoncashSettlementOfWarrantLiabilities" abstract="false" name="NoncashOrPartNoncashSettlementOfWarrantLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_ReclassificationFromOtherNonCurrentAssetsToPropertyPlantAndEquipment" abstract="false" name="ReclassificationFromOtherNonCurrentAssetsToPropertyPlantAndEquipment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_ReclassificationFromOtherNonCurrentAssetsToOperatingLeaseRightOfUseAssets" abstract="false" name="ReclassificationFromOtherNonCurrentAssetsToOperatingLeaseRightOfUseAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="next_AccruedLiabilitiesDebtAndEquityIssuanceCosts" abstract="false" name="AccruedLiabilitiesDebtAndEquityIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
