There’s a Vast Source of Clean Energy Beneath Our Feet. And a Race to Tap It.
There’s a Vast Source of Clean Energy Beneath Our Feet. And a Race to Tap It.
The most audacious vision for geothermal is to drill six miles or more underground where temperatures exceed 750 degrees Fahrenheit. At that point, water goes supercritical and can hold five to 10 times as much energy as normal steam. If it works, experts say, “superhot” geothermal could provide cheap, abundant clean energy anywhere.
Folks in Finland recently tried exactly that, drilling 2 holes 6.4 km deep in Otaniemi, Vantaa. Unfortunately their fracking attempts failed and sufficient flow could not be established between the two wells. Also, temperature at the bottom was 120 C, not enough to get supercritical water (374 C is required). They donated the boreholes to scientific use, someone will try again and try better..
Once the "how" can be sorted out, it should be usable anywhere on Earth, not just volcanic regions. :) But it's not easy.
It's getting big press because one team in the US got their two wells to connect via fracking with sufficient flow and temperature to be useful.
So techniques developed to deep drill for oil can be repurposed to drill for geothermal energy? That's a tiny silver lining. I imagine, as we run out of oil, the drilling companies will start lobbying really aggressively for geothermal in order to keep in business.
And at least geothermal counters all the complaining about "solar panels don't work at night" and so on. The Earth's internal temperature doesn't change much 😆
Get Shinron on that
Didn't Iceland over use geothermal and it caused problems?
There are AFAIK two main risk with using geothermal energy:
Both these risks are during the development of new wells, and once things are completed there is basically no other problems other than that geothermal energy is not infinite and the hot aquifers lower their temperature after some decades. This can make the system too inefficient to be worth continuing operation.
Iceland keeps using geothermal for nearly 1/3 of its energy production. However, Iceland is a really poor benchmark to compare with the rest of the world - in some places, you can cook food on the surface there. :)
Geothermal is one of the few technologies that could serve as a drop-in replacement for nuclear, not to mention coal and gas. Hopefully at least one approach succeeds.
Quaise seems the most interesting, as it's basically a phaser drill.
It is interesting, though I'm dubious about Quaise without an actual full-scale test of it. Lots of things can go wrong between lab and full industrial use.
Lots of things can go wrong
Woskov solves his problems with a gyrotron
and he never has the same problem twice