Networked geothermal power could change cities:

‘Every building sits on a thermal asset’

While temperatures above ground fluctuate throughout the year, the ground stays a stable temperature,
meaning that it is humming with #geothermal #energy that engineers can exploit.

“Every building sits on a thermal asset,” said Cameron Best, director of business development at Brightcore Energy in New York, which deploys geothermal systems.
️“I really don’t think there’s any more efficient or better way to heat and cool our homes.”️

And now the big utilities are beginning to take a good hard look at that system.
A couple of months ago #Eversource #Energy commissioned the US’s first networked geothermal neighbourhood operated by a utility, in Framingham, Massachusetts.

Pipes run down boreholes 600-700ft (about 180-215 metres) deep,
where the temperature of the rock is consistently 55F (13C).
A mixture of water and propylene glycol (a food additive that works here as an antifreeze) pumps through the piping,
absorbing that geothermal energy,
then flows to 31 residential and five commercial buildings, where fully electric #heat #pumps use the liquid to either heat or cool a space.

If deployed across the country, these geothermal systems could go a long way in helping decarbonise buildings, which are responsible for about a third of total greenhouse gas emissions in the US.

Once a system is in place, buildings can draw heat from water pumped from below their foundations,
instead of burning natural gas piped in from afar.
Utilities use the same equipment to deploy networked geothermal as they do for gas lines,
and even the same kind of pipes
– they are just circulating fluid instead of gas.

The networks don’t need special geology to operate, so they can be set up almost anywhere.
The project in Framingham, then, could be the start of something big.

To scale up, a geothermal loop such as Framingham’s might connect to an adjacent neighbourhood, and that one to another.
“In the end, what we would like is if the gas utilities become #thermal #utilities,” said Audrey Schulman, executive director of the nonprofit climate-solutions incubator #HEETlabs
(a spin-off of the climate nonprofit HEET, which began pitching the idea to Eversource and other utilities in 2017).
“Each individual, shared loop can be interconnected, like Lego blocks, to grow bigger and bigger

https://www.theguardian.com/environment/article/2024/aug/09/every-building-sits-on-a-thermal-asset-how-networked-geothermal-power-could-change-cities?CMP=Share_iOSApp_Other