What's up with geothermal power? Will it FORGE ahead?

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Mooderator
Staff member
Nov 18, 2005
104,695
South Puget Sound, WA
The potential for geothermal is huge. It's estimated that it has the potential to cover 8.5% of US household electricity demands. But that potential has several risks. Working deep below the earth's surface in an extremely hot environment is exceptionally hard on current equipment. And a very detailed understanding of the underlying geology is critical. Rushing in, and putting in too large reservoirs, can have serious consequences. Still, the potential is tantalizing and some projects are starting to show promise. Modern fracking technology is leading the way.


The DOE's Frontier Observatory for Research in Geothermal Energy aka FORGE initiative:
 
My former employer spent a lot of time with Pratt &Whitneys Organic Rankine Cycle geothermal technology in the Nevada area. I think the name of the firm was Razor Technologies? They put a lot of equipment out in the field but after a couple of years they gave up and went bankrupt after spending all the government dollars they had been given.

I do wonder there could be if earthquakes like frac water reinjections?

Several years ago I saw a report that if the US tapped the thermal resource around Yellowstone, they could shut down most of the power plants in the South West.
 
Inadvertent earthquakes are a key concern, especially after what happened in Switzerland. Even then there can be undiscovered faults. Leakage is another concern.
 
I was part of the construction of the first geothermal power plant in Alberta. It uses an organic rankine cycle turbine (pentane as the working medium) to produce electricity from about 90c produced water. It also uses a a natural gas turbine with waste heat recovery to add more energy to the process. (Not really a true geothermal plant in most people's eyes).


Fracking certainly is a risk, we get small minor earthquakes all the time here from it. But that's the result of pumping a small lake downhole over the course of days with 16-20 2500hp pumper trucks operating at 6000-9000psi. And we're predominantly in sandstone and shale. Harder rock like granite will have different results when fracked.
 
Hear is a link to a link to an interactive map. The whole east coast is a bit of geo thermal desert. I don’t see many/any economies is scale bringing down geothermal electric generation costs. On the other hand I do think once could do geothermal heatpumps with much better economics than we’re realized in the past.

In summary wind and solar that can be build in an automated factory seem like a better financial choice than geothermal.
 
Hear is a link to a link to an interactive map. The whole east coast is a bit of geo thermal desert. I don’t see many/any economies is scale bringing down geothermal electric generation costs. On the other hand I do think once could do geothermal heatpumps with much better economics than we’re realized in the past.

In summary wind and solar that can be build in an automated factory seem like a better financial choice than geothermal.

I was going to post something similar, but see the situation as a glass half-full... for the US west of the Mississippi. Ring of Fire and all that.

I think that we can def. develop geothermal power using fracking tech. And given how much fracking we are already doing all over, I don't see such a big issue, unless you injecting near a major fault line.

But at the end of the day, it will have to compete with solar and wind + batteries on price.

I could see it being promising there in more Northern climates where a need for seasonal storage would rule out solar+battery baseload, as @ABMax24 has discussed persuasively in the past.
 
Iceland has been building geothermal power plants for decades. If the resource is there its proven tech.
 
A person I worked with was researching possible geothermal investments. The big hot spot under Yellowstone reportedly has the potential for generating an incredible amount of power to supply a big chunk of the west.
 
A person I worked with was researching possible geothermal investments. The big hot spot under Yellowstone reportedly has the potential for generating an incredible amount of power to supply a big chunk of the west.
The amount of energy potential is enormous. I found a paper from 2022 that suggests using massive copper rods in the ground (100 of them along with 1000 steam turbines!) to tap that heat without using water directly--some claim pumping water down there could cause an eruption. Paper claims they could produce 11 quadrillion watt hours/year. If my math is right (?) that is almost triple the electricity usage of the entire US in 2022 (4000 terawatt hours)

link to paper. The cost just for the turbines they estimate is nearly a trillion dollars! However they do think if you took that heat out over time you'd end any thread of an eruption (which would probably kill off billions? if it happened today).