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16 U.S. Code § 838d - Transmission of non-Federal power

The Administrator shall make available to all utilities on a fair and nondiscriminatory basis, any capacity in the Federal transmission system which he determines to be in excess of the capacity required to transmit electric power generated or acquired by the United States.

Statutory Notes and Related Subsidiaries
Transfer of Functions

Functions of Secretary of the Interior with respect to Bonneville Power Administration transferred to Secretary of Energy by section 7152(a)(1)(D), (2) of Title 42, The Public Health and Welfare, with Bonneville Power Administration to be preserved as a distinct organizational entity within Department of Energy and headed by an Administrator.