42 U.S.C. § 16001

The Secretary of Housing and Urban Development shall promote energy conservation in housing that is located on Indian land and assisted with Federal resources through— (1) the use of energy-efficient technologies and innovations (including the procurement of energy-efficient refrigerators and other appliances); (2) the promotion of shared savings contracts; and (3) the use and implementation of such other similar technologies and innovations as the Secretary of Housing and Urban Development considers to be appropriate.