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  <xs:element id="mwh_VestedLLCInterestsMember" abstract="true" name="VestedLLCInterestsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_December2025SecuredNoteMember" abstract="true" name="December2025SecuredNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_ConsultingAgreementsMember" abstract="true" name="ConsultingAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_SecondaryOfferingMember" abstract="true" name="SecondaryOfferingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_RobersonWaiteElectricMember" abstract="true" name="RobersonWaiteElectricMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_SDIAcquisitionMember" abstract="true" name="SDIAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_SpartanAcquisitionMember" abstract="true" name="SpartanAcquisitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="mwh_BusinessCombinationDeferredConsiderationLiability" abstract="false" name="BusinessCombinationDeferredConsiderationLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_BusinessCombinationDeferredConsiderationLiabilityTerm" abstract="false" name="BusinessCombinationDeferredConsiderationLiabilityTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="mwh_BusinessCombinationRecognizedAssetAcquiredContractAssets" abstract="false" name="BusinessCombinationRecognizedAssetAcquiredContractAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAsset" abstract="false" name="BusinessCombinationRecognizedAssetAcquiredOperatingLeaseRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_BusinessCombinationRecognizedLiabilityAssumedContractLiabilities" abstract="false" name="BusinessCombinationRecognizedLiabilityAssumedContractLiabilities" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_BusinessCombinationRecognizedLiabilityAssumedLeaseObligationCurrent" abstract="false" name="BusinessCombinationRecognizedLiabilityAssumedLeaseObligationCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_BusinessCombinationRecognizedLiabilityAssumedLeaseObligationNoncurrent" abstract="false" name="BusinessCombinationRecognizedLiabilityAssumedLeaseObligationNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_BusinessCombinationRecognizedAssetAcquiredToLiabilityAssumedExcessLessAndGoodwillNetOfCashAndCashEquivalents" abstract="false" name="BusinessCombinationRecognizedAssetAcquiredToLiabilityAssumedExcessLessAndGoodwillNetOfCashAndCashEquivalents" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_IncreaseDecreaseCapitalizedProjectDevelopmentCostsRollForward" abstract="true" name="IncreaseDecreaseCapitalizedProjectDevelopmentCostsRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="mwh_CapitalizedProjectDevelopmentCostsAdditions" abstract="false" name="CapitalizedProjectDevelopmentCostsAdditions" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_CapitalizedProjectDevelopmentCostsExpensedFromSaleOfProject" abstract="false" name="CapitalizedProjectDevelopmentCostsExpensedFromSaleOfProject" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_CapitalizedProjectDevelopmentCostsImpairmentLoss" abstract="false" name="CapitalizedProjectDevelopmentCostsImpairmentLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_RebatesReceivableCurrent" abstract="false" name="RebatesReceivableCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_DeferredAcquisitionConsiderationCurrent" abstract="false" name="DeferredAcquisitionConsiderationCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="mwh_ASBEnergyServicesLLCMember" abstract="true" name="ASBEnergyServicesLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
</xs:schema>
