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  <xs:element id="nwe_ColstripOwnershipInUnit3And4January12026AcquiredFromAvistaMember" abstract="true" name="ColstripOwnershipInUnit3And4January12026AcquiredFromAvistaMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_ColstripAcquisitionAndRequestsForCostRecoveryLineItems" abstract="true" name="ColstripAcquisitionAndRequestsForCostRecoveryLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="nwe_TermLoanDue2026EffectiveApril112025Member" abstract="true" name="TermLoanDue2026EffectiveApril112025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_TermLoanDue2026Member" abstract="true" name="TermLoanDue2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_SouthDakotaFirstMortgageBondsDue2036Member" abstract="true" name="SouthDakotaFirstMortgageBondsDue2036Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_SouthDakotaFirstMortgageBondsDue2026Member" abstract="true" name="SouthDakotaFirstMortgageBondsDue2026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_NWCorpTermLoanDue2027Member" abstract="true" name="NWCorpTermLoanDue2027Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_MaximumRatioOfIndebtednessToNetCapitalThresholdPercentage" abstract="false" name="MaximumRatioOfIndebtednessToNetCapitalThresholdPercentage" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nwe_RegulatedElectricSegmentMember" abstract="true" name="RegulatedElectricSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_RegulatedNaturalGasMember" abstract="true" name="RegulatedNaturalGasMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_RegulatedElectricAndNaturalGasSegmentsMember" abstract="true" name="RegulatedElectricAndNaturalGasSegmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_ElectricDomesticRegulatedMember" abstract="true" name="ElectricDomesticRegulatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_GasDomesticRegulatedMember" abstract="true" name="GasDomesticRegulatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_RegulatoryAmortizationMember" abstract="true" name="RegulatoryAmortizationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_TotalRevenueMember" abstract="true" name="TotalRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_ResidentialCustomersMember" abstract="true" name="ResidentialCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_CommercialCustomersMember" abstract="true" name="CommercialCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_IndustrialCustomersMember" abstract="true" name="IndustrialCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_OtherCustomersMember" abstract="true" name="OtherCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_TotalcustomerrevenueMember" abstract="true" name="TotalcustomerrevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_TransmissionCustomersMember" abstract="true" name="TransmissionCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_OtherTariffBasedRevenueMember" abstract="true" name="OtherTariffBasedRevenueMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nwe_OtherEnergySalesRevenue" abstract="false" name="OtherEnergySalesRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nwe_AverageSharesUsedInComputingBasicAndDilutedEarningsPerShareTable" abstract="true" name="AverageSharesUsedInComputingBasicAndDilutedEarningsPerShareTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="nwe_MinimumExpectedFutureEmployerPensionContributionsRemainderofFiscalYear" abstract="false" name="MinimumExpectedFutureEmployerPensionContributionsRemainderofFiscalYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
