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  <xsd:element abstract="true" id="nwe_AccumulatedOtherComprehensiveIncomeTable" name="AccumulatedOtherComprehensiveIncomeTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_AccumulatedOtherComprehensiveIncomeTableTextBlock" name="AccumulatedOtherComprehensiveIncomeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_AcquisitionsAbstract" name="AcquisitionsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_AmortizationOfDebtIssueCostsDiscountAndDeferredHedgeGain" name="AmortizationOfDebtIssueCostsDiscountAndDeferredHedgeGain" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_AverageSharesUsedInComputingBasicAndDilutedEarningsPerShareTable" name="AverageSharesUsedInComputingBasicAndDilutedEarningsPerShareTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_BigStoneGeneratingFacilityMember" name="BigStoneGeneratingFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_CashPaidAbstract" name="CashPaidAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_ColstripUnit4Member" name="ColstripUnit4Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_CommonStockAverageSharePrice" name="CommonStockAverageSharePrice" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_Commonstockaggregategrosssalespricemaximum" name="Commonstockaggregategrosssalespricemaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_CondensedConsolidatedBalanceSheetParentheticalAbstract" name="CondensedConsolidatedBalanceSheetParentheticalAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_CondensedConsolidatedStatementsOfOtherComprehensiveIncomeAbstract" name="CondensedConsolidatedStatementsOfOtherComprehensiveIncomeAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_CostOfDomesticRegulatedElectricAndCostOfNaturalGasPurchases" name="CostOfDomesticRegulatedElectricAndCostOfNaturalGasPurchases" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_CoyoteGeneratingFacilityMember" name="CoyoteGeneratingFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_DaveGatesGeneratingStationMember" name="DaveGatesGeneratingStationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_DemandSideManagementLostRevenueExpectedRecovery" name="DemandSideManagementLostRevenueExpectedRecovery" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_ElectricDomesticRegulatedMember" name="ElectricDomesticRegulatedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_EnvironmentalObligationEstimatedCapitalExpenditures" name="EnvironmentalObligationEstimatedCapitalExpenditures" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="nwe_EnvironmentalRemediationObligationMaximum" name="EnvironmentalRemediationObligationMaximum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="nwe_EnvironmentalRemediationObligationMinimum" name="EnvironmentalRemediationObligationMinimum" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="nwe_EnvironmentalRemediationObligationToBeIncurredDuringNext5Years" name="EnvironmentalRemediationObligationToBeIncurredDuringNext5Years" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_EquityDistributionAgreementMember" name="EquityDistributionAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_EstimatedAggregateGrossContractualPayments" name="EstimatedAggregateGrossContractualPayments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="nwe_Estimatedconveyancepriceofhydroelectricfacility" name="Estimatedconveyancepriceofhydroelectricfacility" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="nwe_Estimatedreferencepricelessconveyanceprice" name="Estimatedreferencepricelessconveyanceprice" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_FinancingActivitiesAbstract" name="FinancingActivitiesAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_GasDomesticRegulatedMember" name="GasDomesticRegulatedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_GoodwillAbstract" name="GoodwillAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_IncomeTaxReconciliationAcceleratedTaxDepreciationFlowThroughAdjustment" name="IncomeTaxReconciliationAcceleratedTaxDepreciationFlowThroughAdjustment" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_KerrProjectMember" name="KerrProjectMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_ManufacturedGasPlantsMember" name="ManufacturedGasPlantsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_Megawattsofgeneration" name="Megawattsofgeneration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_MontanaNaturalGasProductionAssetsMember" name="MontanaNaturalGasProductionAssetsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_NOxEmissionsPerMillionBtuAsCalculatedOnA30dayRollingBasis" name="NOxEmissionsPerMillionBtuAsCalculatedOnA30dayRollingBasis" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_Neal4GeneratingFacilityMember" name="Neal4GeneratingFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_NumberOfCustomers" name="NumberOfCustomers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_NumberOfDaysForBridgeLoanTerm" name="NumberOfDaysForBridgeLoanTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_NumberOfMegawattsOfQualifyingFacility" name="NumberOfMegawattsOfQualifyingFacility" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_NumberOfYearsForEnvironmentalRemediationObligationToBeIncurred" name="NumberOfYearsForEnvironmentalRemediationObligationToBeIncurred" nillable="true" substitutionGroup="xbrli:item" type="us-types:durationStringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_OperationsAndBasisOfConsolidationTable" name="OperationsAndBasisOfConsolidationTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_OwnedAverageLoadServingRequirement" name="OwnedAverageLoadServingRequirement" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_PhysicalPurchaseAndSaleOfGasAndElectricityAtFixedPrices" name="PhysicalPurchaseAndSaleOfGasAndElectricityAtFixedPrices" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_PropertyPlantandEquipmentAcquisitionsAbstract" name="PropertyPlantandEquipmentAcquisitionsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_PublicUtilitiesCapitalStructurePercentageOfDebt" name="PublicUtilitiesCapitalStructurePercentageOfDebt" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_PublicUtilitiesCapitalizedStructurePercentageOfEquity" name="PublicUtilitiesCapitalizedStructurePercentageOfEquity" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_PublicUtilitiesEstimatedRateBaseHydroElectric" name="PublicUtilitiesEstimatedRateBaseHydroElectric" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="nwe_PublicUtilitiesRequestedRateBaseHydroElectric" name="PublicUtilitiesRequestedRateBaseHydroElectric" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="nwe_PublicUtilitiesRequestedReturnOnEquityForBaseRate" name="PublicUtilitiesRequestedReturnOnEquityForBaseRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="instant" />
  <xsd:element id="nwe_RabbiTrustInvestmentFairValueDisclosure" name="RabbiTrustInvestmentFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="nwe_RegulatoryMattersAxis" name="RegulatoryMattersAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_RegulatoryMattersDomain" name="RegulatoryMattersDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="nwe_RestrictedCashFairValueDisclosure" name="RestrictedCashFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant" />
  <xsd:element id="nwe_RevenueofAcquireesinceAcquisitionDateActual" name="RevenueofAcquireesinceAcquisitionDateActual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_ScheduleOfEnvironmentalLiabilitiesAndRegulationTable" name="ScheduleOfEnvironmentalLiabilitiesAndRegulationTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_ScheduleOfRegulatedOperationsTable" name="ScheduleOfRegulatedOperationsTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_SiteContingecyBySiteAxis" name="SiteContingecyBySiteAxis" nillable="true" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="nwe_SiteDomain" name="SiteDomain" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>


