42 U.S. Code § 13452 - Natural gas and electric heating and cooling technologies
(a) Program direction
(1) The Secretary shall conduct a 5-year program, in accordance with sections 13541 and 13542 of this title, on energy efficient natural gas and electric heating and cooling technologies for residential and commercial buildings.
(2) The natural gas heating and cooling program shall include activities on—
(A) thermally activated heat pumps, including absorption heat pumps and engine-driven heat pumps; and