A NetGeo system is a street-segment system of networked ground-source heat pumps. There is a loop of pipe filled with pure water (no glycol added) running up and down the street in the gas utility’s right of way, with service loops running to each building. Each has a heat pump inside their building that pulls heating or cooling thermal energy from the water in the service line, to deliver the needed temperature through that building’s distribution system.

In the fall of 2022, Eversource broke ground on the first gas utility-installed networked geothermal system in the nation. Home Energy Efficiency Team’s (HEET) Learning From the Ground Up research team, including researchers from two national laboratories, U.C. Berkeley, Massachusetts Institute of Technology, and Boston University, will collect data and study outcomes on the installation over the next three years.

Three test boreholes were successfully drilled and monitored by Eversource and the research team. The resulting data was used to evaluate the accuracy of the Eversource team’s thermal capacity models and values in order to size the networked geothermal system appropriately. According to Eversource, the results of the test boreholes confirmed that each location was viable for full construction drilling.

Eversource’s design plan for the entire installation is now complete and construction is set to begin this spring, with a target completion in September.

The enthusiasm and engagement of the Framingham community has been just as exciting as the design and construction process that has been steadily moving forward. This enthusiasm was especially evident at the Fuller Middle School in Framingham last month, where HEET Co-Executive Director Zeyneb Magavi joined Eversource for “Introduce a Girl to Engineering and Science Day.” At the event, middle school girls learned about the thermal science behind the groundbreaking networked geothermal system near their school, a concept created by women at HEET!


HEET (Home Energy Efficiency Team) is a nonprofit climate solutions incubator with a mission to cut carbon emissions now through systems change.