Section 125A. A gas or electric company, generation company, wholesale generation company, or supplier which has been furnishing gas or electricity to the commonwealth or any political subdivision thereof, under a contract that has expired may, until a new contract for supplying gas or electricity to the commonwealth or such political subdivision has lawfully been made, continue to furnish the same to the commonwealth or such political subdivision, notwithstanding any provision of general or special law, city or town charter, or of any ordinance or by-law regulating the making of such contracts. The price, which the commonwealth or such political subdivision shall be liable in contract to pay for gas or electricity so furnished, shall be in accordance with the terms of such expired contract or a schedule of rates filed under section ninety-four or as ordered by the department under the provisions of section ninety-three.