Section 2. Each municipality in the commonwealth shall have the option to participate in the commercial sustainable energy program as a participating municipality by a majority vote of the city or town council, by a majority vote of the board of selectmen or by resolution of its legislative body, as may be appropriate, pursuant to which the municipality shall assess, collect, remit and assign betterment assessments, in return for commercial energy improvements for a benefitted property owner located within such municipality and for costs reasonably incurred in performing such acts.