40 U.S.C. § 591

(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 1 1 See References in Text note below. 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.