Section 17 of Chapter 25A of the Massachusetts General Laws, as so appearing, is hereby amended by inserting after subsection (d) the following subsection:-

(e) Anaerobic digestion facilities that are both operational and qualified as Class I renewable energy generating sources under Section 11F of Chapter 25A of the General Laws prior to the effective date of Section 17 of said Chapter 25A shall be eligible to participate in the incentive program via a one-time procurement for Class I renewable energy certificates created by existing anaerobic digestion facilities. The department shall determine eligibility criteria for existing anaerobic digestion facilities to participate in the one-time procurement, with the total megawatts being procured equal to the combined capacity of all eligible facilities. The one-time procurement shall include a ceiling price equal to or greater than the alternative compliance payment rate, not to exceed double the alternative compliance payment rate established by the department under Section 11F of said Chapter 25A.