The Framingham system consists of a giant underground loop filled with water and antifreeze, similar to the way gas is delivered to several houses in a neighborhood. Water in the loop absorbs heat from underground, which remains at about 55 degrees Fahrenheit all year. Households have their own heat pump units that provide heating and air conditioning, installed by the utility. These take heat from the loop, spike the temperature further, and release that heat as warm air into the homes. For air conditioning, heat is extracted from the home or business and released into the Earth or transported to the next home. Framingham beat out other communities that applied to Eversource to become pilot sites. The city 20 minutes west of Boston is surrounded by Harvard University and Massachusetts Institute of Technology, plus firms like Thermo Fisher Scientific, Pfizer and Novartis. Eric Mauchan said the proximity of so much advanced technology and a state law requiring that greenhouse gas emissions ramp down to zero by 2050 helped make the community receptive. Nikki Bruno, vice president for clean technologies for Eversource, also cited the state’s emissions law as a reason for the pilot. It was also “an opportunity from a decarbonization standpoint,” she said, because Eversource has its own net zero goal.
https://www.wbur.org/news/2024/06/03/climate-solution-massachusetts-framingham-heating-cooling