(a) Except as provided in subsection (b) of this section, any electric distribution company, as defined in § 16-1, that, prior to July 6, 2007, purchased electricity generated by a resources recovery facility, as defined in § 22a-260, owned by, or operated by or for the benefit of, a municipality or municipalities, pursuant to a contract with the owner of such facility requiring the electric distribution company to purchase all of the electricity generated at such facility from waste that originated in the franchise area of the electric distribution company, for a period beginning on the date that the facility began generating electricity and having a duration of not less than twenty years, at the same rate that the electric distribution company charges the municipality or municipalities for electricity, shall pay the rate set forth in the contract or, for contracts entered into and approved during calendar year 1999, the rate established by the authority, for the remaining period of the contract. No electric distribution company shall be required to enter into such a contract on or after July 6, 2007.

(b) Not later than October 1, 2000, and annually thereafter, the authority shall calculate the difference between the amount paid by the electric distribution company pursuant to each such contract in effect during the preceding fiscal year for electricity generated at the facility from waste that originated within such franchise area and the amount that would have been paid had the company been obligated to pay the rate in effect during calendar year 1999, as determined by the authority. The difference, if positive, shall be recovered through the systems benefits charge established under § 16-245l and remitted to the regional resource recovery authority acting on behalf of member municipalities.