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  <xs:element id="nspw_PayabletoaffiliatesMember" abstract="true" name="PayabletoaffiliatesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_SeriesDueJune152041Member" abstract="true" name="SeriesDueJune152041Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_RetailDistributionMember" abstract="true" name="RetailDistributionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_InterchangeMember" abstract="true" name="InterchangeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_AlternativeandOtherMember" abstract="true" name="AlternativeandOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_RegulatedElectricMember" abstract="true" name="RegulatedElectricMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_RegulatedNaturalGasMember" abstract="true" name="RegulatedNaturalGasMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_ResidentialCustomersMember" abstract="true" name="ResidentialCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_CommercialandIndustrialCustomersMember" abstract="true" name="CommercialandIndustrialCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_OtherCustomersMember" abstract="true" name="OtherCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_EffectiveIncomeTaxRateReconciliationAFUDCEquityAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationAFUDCEquityAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_EffectiveIncomeTaxRateReconciliationPlantRelatedExcessDeferredTaxesAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationPlantRelatedExcessDeferredTaxesAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_EffectiveIncomeTaxRateReconciliationAFUDCEquityPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationAFUDCEquityPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nspw_EffectiveIncomeTaxRateReconciliationPlantRelatedExcessDeferredTaxesPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationPlantRelatedExcessDeferredTaxesPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nspw_EffectiveIncomeTaxRateReconciliationOtherRegulatoryAdjustmentsPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationOtherRegulatoryAdjustmentsPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="nspw_DefinedBenefitPlanNetBenefitCostCreditRecognizedBeforeRegulatoryAdjustments" abstract="false" name="DefinedBenefitPlanNetBenefitCostCreditRecognizedBeforeRegulatoryAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_DefinedBenefitPlanCostsNotRecognizedDueToRegulation" abstract="false" name="DefinedBenefitPlanCostsNotRecognizedDueToRegulation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_OtherMGPLandfillorDisposalSitesDomain" abstract="true" name="OtherMGPLandfillorDisposalSitesDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_NumberOfIdentifiedMgpSitesUnderCurrentInvestigationAndOrRemediation" abstract="false" name="NumberOfIdentifiedMgpSitesUnderCurrentInvestigationAndOrRemediation" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="nspw_CostOfIdentifiedMGPLandfillOrDisposalSitesUnderCurrentInvestigationAndorRemediation" abstract="false" name="CostOfIdentifiedMGPLandfillOrDisposalSitesUnderCurrentInvestigationAndorRemediation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_RegulatedElectricSegmentMember" abstract="true" name="RegulatedElectricSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_RegulatedNaturalGasSegmentMember" abstract="true" name="RegulatedNaturalGasSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="nspw_RegulatedOperatingRevenueElectric" abstract="false" name="RegulatedOperatingRevenueElectric" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_ElectricFuelandPurchasedPower" abstract="false" name="ElectricFuelandPurchasedPower" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_RevenuesIncludingIntersegmentRevenues" abstract="false" name="RevenuesIncludingIntersegmentRevenues" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="nspw_NumberOfReportableSegmentsDisclosedByDefinitionFlag" abstract="false" name="NumberOfReportableSegmentsDisclosedByDefinitionFlag" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:booleanItemType"/>
</xs:schema>
