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Eversource employees drilled test pits in Framingham fall 2022 in preparation for installing a neighborhood-wide geothermal system. Photo courtesy of Eversource
As natural gas bans proliferate in Greater Boston communities, utilities are stepping into the search for fossil fuel-free heating and cooling systems.
In Framingham, Eversource is set to break ground on the nation’s first geothermal network led by a utility, providing heat and cooling to 110 customers in 40 residential and commercial buildings on the south side of Normandy Road.
Scheduled to begin operation in time for this fall’s heating season and run for two years, the project will test the financial viability of large-scale geothermal networks.
“No gas utility has ever built this electrification model and then grown it,” said Zeyneb Magavi, co-executive director at Cambridge-based sustainability nonprofit HEET Inc. “We are going to prove the growth model of this new technology.”
The U.S. Department of Energy recently awarded $715,000 to HEET for funding and design of a second Framingham neighborhood system, which would tie into the initial project. HEET will use the grant to assemble a research team to analyze the expanded system’s operation and potential as a model for other communities.
The grant also includes workforce training programs to expand the clean energy workforce, such as drillers and lateral installers.
“The pipefitters and steelworkers are excited to build these and keep their jobs and their pensions,” Magavi said.
Utilities Make Connections in Neighborhood Systems
Air-source electric heat pumps have been the leading alternative to gas- and oil-fired building systems, with programs such as Mass Save offering financial incentives for their installation.
Geothermal systems are another emerging fossil fuel alternative, but require costly installation of pipes into bedrock at least 40 feet below the ground surface, said Eric Bosworth, a senior project manager for Eversource. Neighborhood-scale systems offer economies of scale, but require the involvement of utility companies to build across property lines and public streets.
Participants range from public housing owned by the Framingham Housing Authority to single-family homes, a fire station, service station and cabinetry shop, Bosworth said.
The pilot program in Framingham was approved by the state Department of Public Utilities in 2020 as part of an Eversource rate filing.
The $10.5-million program – paid by ratepayers and coordinated by the utility – analyzed various sites in its National Grid subsidiary’s territory before choosing the Framingham site, Bosworth said. It offers such criteria as relatively shallow bedrock, location in an environmental justice community, a diverse assortment of building types and proximity to bore field sites owned by the city of Framingham and Framingham Housing Authority.
Eversource employees canvassed the neighborhood and held community meetings to encourage participation. To maximize the number of customers signing agreements, property owners were offered a monthly fee of approximately $9, Bosworth said.
“We really want to collect data around how we can design these systems, how they function and potential efficiencies without the added barrier of folks saying, `I can’t afford to participate,’” Bosworth said.
Existing natural gas customers can expect to see an average savings of $50 to $100 a month, he estimated.
A similar geothermal networked pilot project is starting in Merrimack Valley, where University of Massachusetts-Lowell was selected for a National Grid geothermal network pilot. In April, test pits were drilled beneath a campus parking lot in the initial stage of analysis and design.
Digging Deep for Energy Efficiency
Geothermal systems involve drilling water-filled pipes into bedrock to deliver heating and cooling energy to pumps at individual properties, taking advantage of the stable temperatures located not far below the ground surface.
Unlike air source heat pumps, they don’t require installation of compressors outside buildings, but use similar indoor equipment to heat and cool interiors. And geothermal is more effective in extreme cold weather than air source heat pumps, said Chris Schaffner, CEO of Concord-based environmental consultants The Green Engineer Inc.
But the technology hasn’t been widely adopted outside of deep-pocketed institutions with long-term ownership horizons, such as universities.
Boston University took advantage of its ample real estate on Commonwealth Avenue, drilling 31 wells to 1,500 feet to heat and cool its 350,000-square-foot Center for Computing and Data Science, which broke ground in 2020 and opened last December.
Steve Adams
Uncertain timelines about the payback period between installation and break-even have discouraged most commercial developers from including geothermal systems. One exception is Alexandria Real Estate Equities, which designed Moderna’s new headquarters now under construction at 325 Binney St. in Cambridge to rely on geothermal as its primary heating source.
Utilities have incentives to explore alternatives to natural gas as the state of Massachusetts pursues its goal of reducing carbon emissions to net zero standards by 2050.
In 2022, the state legislature authorized a pilot program enabling 10 communities to ban fossil fuel hook-ups in new buildings.
“Utilities like Eversource and National Grid are looking at what their future will be like if the state is really going to hit all-electric in the next 27 or so years,” Schaffner said.
Eversource’s Bosworth said the utility has had discussions with numerous communities within the National Grid gas network seeking to participate in similar pilots, subject to DPU approval.
“Everybody is following along with the progress here, and there’s quite a line of cities that are interested,” he said.
