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Comment by eluketronic | Hacker News Reader

This is pretty interesting but it seems like there’s a massive component of this system that is yet to be proven viable—from the article: “Drilling a hole is challenging enough,” says Tester. “But actually running the reservoir and getting the energy out of the ground safely may be something very, very far off in the future.”

Is there any existing +3km deep geothermal well energy system in use?

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Fervo Energy is making great progress in this area. They've drilled a injector/producer pair, frac'd between them (exactly like oil/gas), and pump water at ~60 L/s. Whatever goes into the injector comes out the producer a few hours later much hotter. Their proof of concept produces 3 MW, and uses ~1MW to power the injection pumps. They are doing a full scale plant in Utah now, and expect ~8 MW net for each injector/producer pair.

https://eartharxiv.org/repository/view/5704/

https://fervoenergy.com/fervo-energy-breaks-ground-on-the-wo...

3km would be far below average for new oil and gas wells in America. Climate change sucks but the technology for punching holes in the ground with extreme aspect ratios is really cool. A reason I am more interested in geothermal than nuclear for "base load" generation is because geothermal can reuse our existing drilling technology and workforce.

Yeah, and think about the amount of political support you could get for geothermal projects if workers from the oil and gas sector could see a clear and easy path to adapt their skills.

Globally viable geothermal power generation would be an absolute game changer for fighting climate change. It doesn’t have to be better than nuclear. If it’s even close to being as good, the benefits of getting ex oil/gas people/companies on board would more than outweigh the difference. The growth rate could potentially hit levels that make a substantial impact on climate change within a decade of the initial ramp.

Geo would make a good transition project for the drilling side of the business.

It's counter intuitive but if we did move that way we need a LOT more petro infrastructure going forward. And without irony it would be better for us.

Capturing all the wasted natural gas (that gets flared off) as a reorient to maintain existing wells lowers carbon foot print and makes the use of gas less attractive due to cost.

Petrochemical products aren't going away any time soon. Unless we want to go back to hunting whales for things like lubricants. Having useful plastics (because there are tons of medical uses). And we're not getting rid of fertilizer (cause feeding 8 billion people is hard).

There are reasons to keep the drilling side and the current matinence side around doing what they do today while lowering carbon foot print.

> Unless we want to go back to hunting whales for things like lubricants. Having useful plastics

We know how to make both from many other process. PLA plastic (commonly used for 3d printing) is commercially made from plant sources as well (I wasn't able to find a source for if it all is or just some). There are plant based oils that are biodegradable that you could put into any transmission today (meet OEM requirements) - they cost about 6x what regular oil costs though. If that isn't good enough the process to make synthetic oil just need carbon (ideally in the form of CO, but we could use CO2), water, and energy and from there we can engineer any hydrocarbon you want - again at much high cost.

Pumping oil from the ground is cheap though, so it is hard to compete with something else. We know how to do it though. If you are a chemical engineer there is a lot of money in reducing costs (though I'm not making any claim this is possible, only if you can there is money)

PLA does come from corn! And you're right that we do have plant based sources that are 6x the cost for a lot of things.

We dump fertilizer made from petrochemical on the plants to grow them.

And that's the rub. I have to wonder how much oil we use, to grow corn, to make ethanol, to save oil...

EDIT: I Had to do the math I needed to know!

173.3 Bushels of corn per acre: https://www.nass.usda.gov/Statistics_by_State/Iowa/Publicati...

140 gallons of fossil fuel per acre of corn: https://www.nass.usda.gov/Statistics_by_State/Iowa/Publicati...

A bushel of field corn can produce 2.77 gallons of ethanol:

Assuming these numbers are right, it isnt so bad...

> Petrochemical products aren't going away any time soon. Unless we want to go back to hunting whales for things like lubricants.

Synthetic lubricants (like Mobil-1) are a thing.

"Synthetic oil is a lubricant consisting of chemical compounds that are artificially modified or synthesised. Synthetic lubricants can be manufactured using chemically modified petroleum components rather than whole crude oil, but can also be synthesized from other raw materials. The base material, however, is still overwhelmingly crude oil that is distilled and then modified physically and chemically. The actual synthesis process and composition of additives is generally a commercial trade secret and will vary among producers."

https://en.wikipedia.org/wiki/Synthetic_oil

Polyalphaolefins (PAOs), the most common synthetic oil, are produced from ethylene. In the US, this overwhelmingly means being produced from natural gas, as US fracked gas is rich in ethane, the feedstock for ethylene production.

https://www.cpchem.com/what-we-do/solutions/polyalphaolefins...

Penzoil is at least upfront that they make their synthetics from natural gas.

Mobile-1 is happy to tell you that they dont use natural gas.

But that doesn't mean that they dont use hydrocarbons pumped from the ground to make it. Synthetic is just a marketing term: http://xtremerevolution.net/a-defining-moment-for-synthetics...

Lots of options if someone is willing to pay 5x as much. Most options are better as well, but not 5x the price better.

Technology and workforce are not the limitation of nuclear.

Utah FORGE is the deepest I'm aware of: https://utahforge.com/project-research. Well 58-32 goes to 2.2km. 78B-32 goes to 2.9km. 16B(78)-32 appears to break 3km.

But FORGE is mostly based around research, from what I understand, rather than rolling out broad-based commercial geothermal.

And what do you make the pipes out of that do not get destroyed from living at those depths?

Steel

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