(a) In addition to the power conferred by this chapter on the commission, it shall possess with reference to all public utilities within its jurisdiction all the other powers conferred with reference to railroads regulated by the department of transportation or transportation companies regulated by the department of safety as provided by chapters 3 and 5 of this title.

(b) Where any existing contract between any public utility and any municipality specifies that particular things, other than charging certain rates, tolls or fares, shall continue to be done by such public utility, or the nature, kind, and quality of any particular service to be rendered by the public utility to the municipality or its people, nothing in this section nor in this title shall be construed to authorize the commission to excuse such public utility from continuing to do such specified things or from continuing to render and perform the service of at least the nature, kind and quality specified in any such existing contract; but, all these things involving the cost of the service shall be taken into consideration by the commission in exercising its power to pass upon the reasonableness of any rate, fare, or charge hereafter to be made by such public utility.

(c) No provision of this section or of this title shall be construed to alter or impair any existing contract between any public utility and any municipality whereby it has been agreed that any payments of money, in addition to proper ad valorem taxes, shall be made by any such public utility to or for the benefit of any such municipality or its people, but all such things, involving the cost of the service, shall be taken into consideration by the commission in exercising its power to pass upon the reasonableness of any rate, fare or charge hereafter to be made by such public utility.

(d) When any public utility regulated by the commission supplies its services to consumers who use solar or wind-powered equipment as a source of energy, such public utility shall not discriminate against such consumers by its rates, fees or charges or by altering the availability or quality of energy. Any consumer who uses solar, wind power, or other auxiliary source of energy shall install and operate the equipment, property, or appliance for such energy source in compliance with any state or local code or regulation applicable to the safe operation of such equipment, property, or appliance.

(e) Any franchise payment or other payment for the use of public streets, alleys or other public places or any license, privilege, occupation or excise tax payment, which after February 24, 1961, may be made by a utility to a municipality or other political subdivision, except such taxes as are presently provided for under existing statutes and except such franchise payment or other payments as are presently exacted from the utility pursuant to the terms of any existing franchise or other agreement, shall, insofar as practicable, be billed pro rata to the utility customers receiving local service within the municipality or political subdivision receiving such payments, and shall not otherwise be considered by the commission in fixing the rates and charges of the utility.

(f) The commission shall further have jurisdiction over all utility districts created pursuant to Tennessee law, to the extent that the exercise of such jurisdiction is provided by title 7, chapter 82 and Acts 1951, ch. 51 as provided in this chapter or as amended.