Unlikely alliance builds cleaner geothermal energy network in Massachusetts community

Geoff Bennett:

Now the story of an unlikely partnership between a utility company and climate activists and how they worked together to help one community switch its heating and cooling to a cleaner source.

Science correspondent Miles O'Brien has the story, part of our Tipping Point coverage on energy and climate.

Miles O’Brien:

Retired schoolteacher Carol Canova has lived in this tiny little house in Framingham, Massachusetts for 30 years. From this humble perch, she has experienced firsthand a historic energy transition. She started with an oil-burning furnace, then switched to gas, and now heats and cools with an electric heat pump attached to a geothermal well.

Carol Canova, Framingham, Massachusetts, Resident:

I was told it would be even heat. I was told it would be efficient and so forth. But seeing is believing. I'd never been in a house that every place in the house was the same temperature.

Miles O’Brien:

Canova is part of a first-in-the-nation pilot by utility giant Eversource. It's a one-mile network of underground pipes connecting three dozen homes and municipal buildings to a shared geothermal well.

It's called networked geothermal, and if it works here, it could be a blueprint for utilities nationwide.

Carol Canova:

So I thought, oh, electricity is expensive. So I'm expecting it's going to be more expensive. What I find out is, it's overall cheaper.

Miles O’Brien:

Heat pumps live up to their name. They move heat. In the summer, they pump heat out of your home. In the winter, they bring it in. How hard they have to work and how much electricity they use depends on the temperature difference between inside and outside. The greater the gap, the more energy they need.

Shallow geothermal wells tap into the earth's steady underground temperature, about 55 degrees year-round. Water with antifreeze circulates through buried pipes, absorbing or releasing heat at that consistent temperature. A heat pump paired with a geothermal well has less work to do and is far more efficient no matter the weather above.

The catch? Drilling a geothermal well is very expensive, but none of the volunteers in this project paid a dime for either the well or the heat pump.

Carol Canova:

When Eversource offered it, I thought, you know what, this is like winning the lottery.

Nikki Bruno, Vice President, Eversource:

Everything else is buried in underground, except for the heat pumps.

Miles O’Brien:

Nikki Bruno is an Eversource V.P.

Nikki Bruno:

So, right outside this building is what we call the main bore field.

Miles O’Brien:

She showed me the pump house, which controls the entire system. It's the only visible sign of the geothermal network.

Nikki Bruno:

Those bores are 600 to 700 pipes that allow the water-based fluid to circulate and exchange energy with the underground.

Miles O’Brien:

Besides many homes like Carol's, heat pumps attached to the geothermal network are in use at a school administration building, a fire station, and a public housing development.

It's an $18.6 million project that comes amid significant changes in regulations. Massachusetts and the other states in the Eversource territory have aggressive climate goals and mandates.

Nikki Bruno:

How do we start offering something different? How can we produce a decarbonized product for our customers, while keeping safe, reliable and I will say as affordable as possible service to customers?

Miles O’Brien:

The idea was born of an unlikely partnership between utility executives and climate activists, among them, Zeybeb Magavi, the executive director of the nonprofit HEET, the Home Energy Efficiency Team. It's a grassroots group that started out by banding together to insulate their homes. They were looking for a way to make a bigger dent.

Zeybeb Magavi, Executive Director, HEET:

We really became aware of kind of a rock-and-a-hard place problem, where we have a gas system that actually we have pipes in the ground from President Lincoln's time.

Miles O’Brien:

Their focus on creaky, leaky gas pipes led them to a moment of insight and inspiration.

Zeybeb Magavi:

The ground, the bedrock, the water all around us is thermal energy, which we can tap. And that's kind of an exciting awakening thing to realize. We could potentially build a utility street by street that was pipes filled with water, maintained and managed by the gas utility, who — becomes a thermal utility.

This infrastructure would be in a way like the roots of our new energy system, right?

Miles O’Brien:

Even federal researchers are bullish. A study by the Oak Ridge National Laboratory found that mass adoption of geothermal heat pumps could reduce the demand for electricity by 13 percent in the next 25 years. But the idea isn't new.

Let's go down in the boiler room. Here we go. You got people down here shoveling coal, right?

Jeff Tester, Engineering Professor, Cornell University:

This is our living laboratory.

Miles O’Brien:

Cornell University engineering professor Jeff Tester built his home in Ithaca, New York, as a living lab of efficiency, solar thermal, photovoltaics, and a heat pump that taps into a geothermal well buried in his backyard.

He's been advocating for ways to tap the heat beneath our feet since the 1970s, when he helped pioneer a novel geothermal energy concept at the Los Alamos National Laboratory.

Jeff Tester:

One method of extracting heat or mining heat from under the surface of the earth is to create a reservoir.

Miles O’Brien:

He looks back on those days with nostalgia.

Jeff Tester:

They were very supportive of trying new things in those days. We weren't afraid to try something.

Miles O’Brien:

For about 25 years, Cornell has harnessed a natural thermal engine to keep its campus cool. A district-chilling system taps 39-degree water from the depths of Cayuga Lake to cool more than 100 buildings.

Now the university is looking to go deeper and warmer. Jeff Tester is the principal investigator on a groundbreaking project to introduce geothermal heating to the campus. In 2022, his team drilled a nearly two-mile-deep test borehole to assess the available heat resources here.

Jeff Tester:

I feel like I have been training all my life for the day when we actually would see this happen on a campus like Cornell.

Miles O’Brien:

But he's still waiting, looking for money to build a geothermal network of pipes filled with hot water to heat the campus. He says society places great value on fossil fuels and electricity.

Jeff Tester:

But heat is not viewed that way in the same way, and I think we need a fairer system of what I refer to as an equivalent way to actually look at the benefits from clean heating versus clean electricity versus clean fuels. And we're not doing that right now. So we need a new value system for energy.

Miles O’Brien:

The Trump administration apparently does value geothermal. Energy Secretary Chris Wright consistently emphasizes it as a priority, making it the only renewable energy source currently in favor.

Zeybeb Magavi:

It's something we can agree on. It's the ground beneath our feet. Turns out we have common ground.

Miles O’Brien:

And it appears to be growing. Plans are now in place to double the size of the Framingham geothermal network starting next year. Common ground may be hard to find these days, but perhaps it's not far beneath the surface.

For the "PBS News Hour," I'm Miles O'Brien in Framingham, Massachusetts.