Underground Thermal Energy Networks Are Becoming Crucial To the US’s Energy Future

Thirteen US states are now implementing underground thermal energy networks to reduce buildings’ carbon emissions as part of a nationwide push to adopt cleaner energy sources. Thermal energy networks use pipe loops that connect multiple buildings and provide heating and cooling through water-source heat pumps. Geothermal heat is commonly used in these networks, but it is also possible to bring in waste heat from other buildings through the sewer system. When installed, these networks can provide efficient, fossil fuel-free heating and cooling to commercial and residential buildings. Thanks to legislative backing and widespread support from utility companies and labor unions they’re likely to become an increasingly significant part of the future energy mix in the US.

“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.” While the projects are still at the planning and regulatory stage in most of the 13 states, construction is already underway in some. […] The advantages of thermal energy networks extend beyond reducing carbon emissions. Scaling them up from a few buildings to a community or utility level can also help make the grid more resilient and efficient. Magavi says every time a “loop” of thermal energy network is added to the grid, its ability to predict and manage power flow becomes more accurate. This interconnectedness helps the system become more resilient in high-stress situations.