Resulting utility cost savings and conservation-related cost savings, income from lands granted for the use of certain institutions and public buildings and deposited in income funds for such institutions and buildings pursuant to Section 19-1-17 N.M. Stat. Ann. or special funds of institutions may be appropriated and pledged for payments pursuant to a guaranteed utility savings contract or related lease-purchase agreement or installment payment contract pursuant to the Public Facility Energy Efficiency and Water Conservation Act. Money appropriated for that purpose shall be deposited in a special fund or account of the institution or fund and that revenue and no other revenue shall be pledged for payments pursuant to the Public Facility Energy Efficiency and Water Conservation Act.