Miss. Code § 77-5-301
The counties of the State of Mississippi, acting by and through their boards of supervisors, are hereby authorized to erect, construct, purchase, and/or acquire and/or maintain and/or operate electric light plants, electric transmission lines, electric distribution system substations, and/or all electrical appurtenances and/or electric appliances and/or electric equipment necessary or useful in the operation or distribution of electric power and/or electric energy. The boards of supervisors shall have full authority to purchase, rent, lease, and/or acquire any and/or all kinds of property, real and/or personal, in order to carry out said powers and to enter into any and all contracts with the Tennessee Valley Authority and/or any similar agency of the federal government, which may be deemed necessary or expedient by such boards in exercising such powers. The boards of supervisors shall have full control over the erection, construction, maintenance, and operation of such properties, with full powers to pass rules for the control, operation, and maintenance of such properties, the rate to be charged, the manner of operation, and the employment of officials and employees of every kind.
Miss. Code § 77-5-301