40 U.S.C. § 591
Purchase of electricity
(a) General Limitation on Use of Amounts.—
A department, agency, or instrumentality of the Federal Government may not use amounts appropriated or made available by any law to purchase electricity in a manner inconsistent with state law governing the provision of electric utility service, including—
(1)
state utility commission rulings; and
(2)
electric utility franchises or service territories established under state statute, state regulation, or state-approved territorial agreements.
(b) Exceptions.—
(1) Energy savings.—
This section does not preclude the head of a federal agency from entering into a contract under section 801 of the National Energy Conservation Policy Act ( 42 U.S.C. 8287 ).
(2) Energy savings for military installations.—
This section does not preclude the Secretary of a military department from—
(A)
entering into a contract under section 2394 of title 10; or
(B)
purchasing electricity from any provider if the Secretary finds that the utility having the applicable state-approved franchise (or other service authorization) is unwilling or unable to meet unusual standards of service reliability that are necessary for purposes of national defense.
( Pub. L. 107–217 , Aug. 21, 2002 , 116 Stat. 1118 .)