"Ground source heat pumps in general are one of the most efficient methods of heating and cooling, and then networking them together you get additional efficiencies,” [said Audrey Schulman, HEET Co-Founder and Co-Executive Director.] That efficiency is why 26 utilities representing 50% of all gas customers in the country are actively exploring this technology, according to HEET.

In April, the U.S. Department of Energy announced first-ever backing for 11 community geothermal projects in 10 states, while several states have passed new laws to boost the strategy.Geothermal is the missing piece in a move to green energy, Magavi said, and as gas infrastructure ages and more localities put in place green goals, the opportunity is vast – and not just for the rich.

Avoiding or minimizing economic dislocation during this energy transition will require utilities, political leaders, and environmentalists to work together, said Zeyneb Magavi, co-executive director of HEET, a Boston-based nonprofit that finds solutions to lowering carbon emissions. Simply putting gas utilities out of business is not the answer, she said.

After decades of relative obscurity—at least in the U.S.—geothermal is rapidly gaining acceptance as a powerful source of renewable energy. Companies like Fervo Energy have made headlines recently for their efforts to generate electricity by drilling deep into the earth, where temperatures reach hundreds of degrees, using technically complex, and potentially high-risk approaches.

“Heat is the largest source of waste energy and it’s an untapped resource,” says Zeyneb Magavi, co-executive director at clean energy nonprofit HEET (Home Energy Efficiency Team). “Once we have a thermal energy network, we can tap into that resource by moving it to where we need it.”

Massachusetts has an ambitious plan to clean up the environment. The goal is to reduce carbon emissions by half by the end of the decade, and completely by 2050. Getting there will require innovation, like the use of geothermal heating and cooling.