16 U.S.C. § 2627 — Relationship to State law

(a) Revenue and rate of return Nothing in this chapter must authorize or require the recovery by an electric utility of revenues, or of a rate of return, more than, or less than, the amount of revenues or the rate of return determined to be lawful under any other provision of law.

(b) State authority Nothing in this chapter prohibits any State regulatory authority or nonregulated electric utility from adopting, under State law, any standard or rule affecting electric utilities which is different from any standard established by this subchapter.

(c) Federal agencies about any electric utility which is a Federal agency, and about the Tennessee Valley Authority when it is treated as a State regulatory authority as provided in section 2602(17) of this title , any reference in section 2621 or 2623 of this title to State law is treated as a reference to Federal law.