The Postmaster General shall actively undertake a program to identify and procure energy efficiency products for use in its facilities. In carrying out this subsection, the Postmaster General shall, to the maximum extent practicable, incorporate energy efficient information available on Federal Supply Schedules maintained by the General Services Administration and the Defense Logistics Agency.
42 U.S. Code § 8262h - United States Postal Service energy regulations
Pub. L. 102–486, title I, § 164, Oct. 24, 1992, 106 Stat. 2860, directed Postmaster General to conduct an energy survey, as defined in 42 U.S.C. 8259(5), for purposes of determining maximum potential cost effective energy savings that may be achieved in a representative sample of buildings owned or leased by United States Postal Service in different areas of the country, making recommendations for cost effective energy efficiency and renewable energy improvements in those buildings and in other similar United States Postal Service buildings, and identifying barriers which may prevent the United States Postal Service from complying with energy management goals, and further directed Postmaster General to transmit to Congress within 180 days after Oct. 24, 1992, a plan for implementing this survey, and to report to Congress on the findings and conclusions of such survey as soon as practicable after its completion.