Tenn. Code § 7-39-316
Any municipality has the power, together with all powers incidental thereto or necessary for the performance thereof, exercisable alone or jointly with any other public agency, acting by resolution of its governing body, to purchase, by contract or other agreement, natural gas or electrical power, or both, from an energy acquisition corporation. Any municipality has the power to enter into any contract or arrangement with a corporation for the acquisition of natural gas or natural gas substitutes or electrical power, containing such terms, covenants, representations, warranties and provisions and for such period or duration as the governing body of the municipality shall determine, including contracts containing the agreement of the municipality to take or pay for any gas, gas substitutes or electrical power provided by the corporation to the municipality.
T.C.A. § 7-39-316