Mass Save is a collaborative of Massachusetts' natural gas and electric utilities and energy efficiency service providers, in ... cluding Berkshire Gas, Blackstone Gas Company, Cape Light Compact, Columbia Gas of Massachusetts, Eversource, Liberty Utilities, National Grid and Unitil. We empower residents, businesses, and communities to make energy efficient upgrades by offering a wide range of services, rebates, incentives, trainings, and information. These programs and services are managed and delivered by electric and gas Sponsors (working closely with the Massachusetts Department of Energy Resources), providing the energy expertise to help you save energy and money. Through the joint efforts of the Mass Save collaborative, Massachusetts has earned top ranking as the #1 state in the nation for energy efficiency according to the American Council for an Energy-Efficient Economy (ACEEE). read more