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  <xs:element id="tac_ParentCompanyandTransAltaRenewablesInc.Member" abstract="true" name="ParentCompanyandTransAltaRenewablesInc.Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
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  <xs:element id="tac_ContractWithCustomersMember" abstract="true" name="ContractWithCustomersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
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</xs:schema>
