Now the story of an unlikely partnership between a utility company and climate activists

and how they work 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.

Retired schoolteacher Carol Canova has lived in this tidy 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.

I was told it would be even heat. I was told it would be efficient and so forth.

But seeing as believing. I'd never been in a house that every place in the house was the same temperature.

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. 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.

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.

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