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Yeah right. They drilled in Strasbourg, France, to get this "free" energy. When they entered production, the city was experiencing an earthquake every month, waking the city at night. After a magnitude 4 earthquake, they finally shut down the plant.

A town in Germany is devastated also due to geothermal power: https://en.m.wikipedia.org/wiki/Staufen_im_Breisgau



The Staufen im Breisgau mishap is one of the learning experiences of geothermal energy, like analyzing the type of rock that you plan to drill through, and maybe not drill in a town center.

But apart from that, you seem to have misinterpreted the Quaise technology, mixing apples and oranges. This is not conventional drilling which can cause water to flow into adjacent rock (not to mention fracking which deliberately cracks the bedrock to allow water to flow through).

This technology is vaporizing the rock and at the same time creating a sealed shaft which funnels the water directly to the great depths where the water can reach supercritical steam state, and so avoiding the issues that caused the Staufen im Breisgau mishap.


A conventional drill can be cemented as well, the technology is already existing but mishap happened anyway

Another town near Strasbourg is devastated like staufen Im breigsbau: Lochwiller. With the same issue as staufen, except that in this case it was a family who drilled to heat their home.


are you telling me a family drilled to heat their home and caused earthquake? that sounds absurd


The straufen issue wasn't an earthquake. A chemical reaction occured when water mixed with an anhydrous layer, causing the ground to swell up to 12 inches per the linked wiki article.


The really interesting question might sound even more absurd: did that earthquake release stress that would have been released sooner or (worse:) later anyways? Should people affected by the earthquake thank the family for releasing stress before more accumulate?


Not absurd. Do you think the same might apply to quakes caused by fracking?


That's literally what I've been wondering next. The question marks where genuine, not rhetoric.

(I can't claim that this is always the case with my question marks, so I'm in no position to complain if they are not taken at face value)


Same. Not a rhetorical question.

Wildfires are the clear analogue. I wonder if it actually works that way. I would guess not. The size and strength of a massive earthquake is just so hard to understand. That the Richter scale is logarithmic is just incredible. A few small quakes here and there seem unlikely to meaningfully detract from its power.


Assuming this is a real problem, wouldn't you just put your geothermal power plant well outside of any city?

Doesn't even have to be somewhere where there are no buildings. Just somewhere where hardening the few existing buildings against small earthquakes etc won't be too expensive.


Many countries have almost no wilderness left; everything is either urban or agriculture or mountains with no convenient place for an earthquake.


Seismic disturbances are generally a concern for dense urban areas. It seems unlikely that agricultural areas would care that much.


Is there any conceivable burden urbanites don't imagine the people and land outside urban areas can tolerate?

We don't live in grass yurts you know. Bridges and dams are a thing. Earthquakes are a problem. Deep fracking operations have demonstrated this already.


> Is there any conceivable burden urbanites don't imagine the people and land outside urban areas can tolerate?

The burden of wealth.


Huh? Read my comment. I did not suggest there are no building in non-urban areas. Just fewer, and thus it would be less expensive to make them earthquake proof.

Japan deals with natural earthquakes all the time. Earthquakes stronger than whatever a bit of geothermal energy production would produce.


Because Japan deals with natural earthquakes all the time, japan has quake-safety standards. They were written in blood, and don’t exist in places which don’t routinely have earthquakes, because quake safety is constraining and expensive.

Retrofitting an entire country for quake safety because you’ve decided to create artificial earthquakes is inane.


Who suggested an entire country? We are talking about small-ish areas.


You have literally no idea how wide the geological destabilisation would reach.


Given the example quoted, not all that far. One article talked about Strasbourg having some minor wobbles, not the entire region. They would have surely seized on the sensationalism of reporting a wider impact.

Of course, there's no clear border. Wobbles will be biggest at the epicentre and get smaller further out.

In any case, you just do the actuarial math, and figure out how much it would cost to wobble-prove buildings in the area in question, and stick that into your cost benefit analysis. It's not like other forms of energy generation are completely without downsides either.


> We don't live in grass yurts you know. Bridges and dams are a thing. Earthquakes are a problem. Deep fracking operations have demonstrated this already.

What percentage of rural areas are situated in close proximity to large dams and bridges?


Your statement is unclear, are you saying it doesn’t matter if dams and bridges get destroyed, or that it doesn’t matter if rural habitations get destroyed as long as they’re not destroyed near infrastructure?


It’s perfectly clear if you read it without trying to be deliberately obtuse.


In Germany you will be hard-pressed to find a place more than 10km/6mi from the nearest village with more than 500 inhabitants. Those people don't like earthquakes or cracked buildings either. Same thing in England.


Pay to earthquake proof their building and give them a bit of extra money on top. It's not that hard. Have a sort of auction to see who in the vicinity it willing to accept the geothermal plant for the cheapest.

Keep in mind that Germany has plenty of open pit lignite mines. Like eg https://en.wikipedia.org/wiki/United_Schleenhain_coal_mine

The disruption from geothermal is minuscule by comparison.


Agriculture relies on stable water supply…


"It seems unlikely that agricultural areas would care that much."

Why would you think that? Because the peasants are all too stupid to notice an earthquake that damage their houses?

Sure, fewer people would be affected, than in a dense city, but the problem solution of: out of sight, out of mind, is fascinating.


You know that you can earthquake proof buildings?

Offer to do that plus a bit of extra money on top, and you'll find plenty of rural takers. Pick the cheapest bidder.


There surely are various solutions and it is also a solution to shift side effects to areas where fewer people are affected (and more easily compensated) - but the tone of that statement above was "who cares for rural areas" at least I read it like this, because why else would rural people not care about it?


Which statement are you referring to?

I do agree with the commenter who said that we don't need to earthquake proof agricultural land itself. Especially not against minor wobbles. Fields just lie there.

(Just to avoid confusion: any buildings close to agricultural land need to be considered, of course. I am talking purely about the fields.)


> Why would you think that? Because the peasants are all too stupid to notice an earthquake that damage their houses?

Yes, exactly. I also don’t expect dense residential buildings prone to earthquakes to be prevalent in low density sparsely populated agricultural areas.

There is nothing “fascinating” except that stating facts about rural areas immediately brings out the worst kinds of trolls out of the woodwork.


It seems like this is a real problem: https://news.stanford.edu/2019/05/23/lessons-south-korea-sol...

That said, it also seems like this proposed technique is very different and probably wouldn't have the same issues.


> Assuming this is a real problem, wouldn't you just put your geothermal power plant well outside of any city?

The US’ fracking experiments show ”well outside of any city” is nowhere near enough.


Why? How much damage has been done?


In every state where fracking got authorised, earthquakes above 3.0 have increased by an order of magnitude (or even appeared where they were considered essentially inexistent).

Hundreds if not thousands of buildings have been damaged across OK and TX because they’d been built with no quake resistance as they’d been built in zones considered inactive, insurers have jacked up their rates and the USGS had to revise their risk maps.

The risk to populations is also non-negligible, because aside from a lack of quake-proof constructions the populations are not trained for or aware of quake safety for the same reason that the areas are historically stable.

I don’t think that’s happened yet in the US (as no fracking quake has exceeded 5.0 yet), but in 2019 fracking started killing people in china: the Sichuan basin, historically a geologically very stable region, got hit with 4 quakes between 4.9 and 6.0, at least 15 died and hundreds were injured.


Thanks!

Seems all pretty manageable on the humongous scale of 'this could be our main source of energy'.

Eg burning coal or oil kills a lot more people directly and indirectly.


> Just somewhere where hardening the few existing buildings against small earthquakes etc won't be too expensive.

So, expending twice on a bad idea ? Seriously, what do you think will happen ?

And even it was technically possible, how do you insure a company like that ? Will the plant operator be responsible for the repairs and damages when they destabilize an entire region ?


> So, expending twice on a bad idea ? Seriously, what do you think will happen ?

What do you mean? A few really minor earthquakes are all that was reported by the comment I was replying to. So I'd assume more really minor earthquakes.

> And even it was technically possible, how do you insure a company like that ?

The usual way of paying an insurance company?

> Will the plant operator be responsible for the repairs and damages when they destabilize an entire region ?

Depends on the jurisdiction. But sure, you can make the plant operator responsible for that and responsible for having gigantic insurance coverage.

(Just look at whatever liability people who operate dams have today. A breakage of a major dam would also devastate entire regions. So whatever arrangements are good enough for that use case are probably good enough here.)


I don't think the "entire region"s involved would be big enough to make insurance difficult to implement.


The goal of the plant was to provide heat for Strasbourg, so it has to be near the city.


Yes. Originally I typed a longer version of my comment that had a section on heat vs electricity.

Basically, the idea I proposed would only work for generating electricity, not for using the heat directly.


Tom Scott did a video on Staufen im Breisgau in 2017: https://www.youtube.com/watch?v=zOgle88sKro


I believe you may have missed what these folks are doing differently.

To put it into context, geothermal energy that taps underground water reservoirs near heat sources has been shown to cause earthquakes and other not good side effects. All of those effects are associated with water being released from aquifers that were previously sealed, or ground changes due to water incursion into previously dry structures (which happened in the reference German town). These guys however are digging below all of that. In fact finding water that near the surface would likely cause them to determine the location unsuitable.

Modern geothermal plants are "binary" in that they have their own water loop which goes down, gets heated, and then comes back as steam. A good explainer is here: https://www.eia.gov/energyexplained/geothermal/geothermal-po...

What these guys propose doing is essentially drilling into rock 6+ miles down. That is about 5 to 10 times deeper than current plants. Using the heat from the rock which is near 1000 degrees to heat water that they pump through it into steam and recover through the turbines. The whole "pipe" from well head to return is nominally sealed with the vitrified walls created by the microwaving process.

Let's assume (and I don't know since I don't work for these guys but we need numbers if we're going to guess at things) that their "drilling" with microwaves technology leaves behind a 12" diameter hole that is > 6 miles deep. And we can drill two of those holes in such a way that they meet at their maximum depth. I'm imagining holes that start on the surface 100+ yards (or meters) apart drilled with a slight angle to meet when they are 6+ miles deep. How much power could we expect to get out of that?

So let's do a little math, water weighs about .03621 lbs/cubic inch. And a 1ft tall, 1ft diameter cylinder of water would way about 49 lbs. A mile is 5280 feet so a mile high column of water, 12" in diameter, would weigh 258,851 lbs, and a 6 mile high column would weigh 1,553,283 lbs (a bit under 777 tons) so the force at the bottom of the column would be about 13,734 psi. At 935F it would pretty much instantly convert to 'dry' steam, and could likely be recovered at about 10,000psi on the other side of the well.

It has been a long time since I had to figure out from a steam table how much energy was extractable from super heated steam, but it is a lot. It goes through the turbine, piped through a cooling tower to condense it back into water, and then dropped back into the source hole.

The risk of earthquakes and other geo-technical disturbances is minimized by what is essentially a closed loop system.

Now it is true that you're going to cool the crust (energy is conserved after all and if you're running turbines it means the crust is cooling) the question then is how quickly is that heat returned by other actions. And of course if you were to pull "all" the energy out fast enough this way you could presumably "freeze" the core of the Earth and that would be a bad thing, but we're talking about way more energy than the entire world consumes in a centuries and I'm not sure how to judge that risk compared to the heat generation mechanisms inside the planet. An actual geologist probably has an idea.


> Let's assume (and I don't know since I don't work for these guys but we need numbers if we're going to guess at things) that their "drilling" with microwaves technology leaves behind a 12" diameter hole that is > 6 miles deep. And we can drill two of those holes in such a way that they meet at their maximum depth. I'm imagining holes that start on the surface 100+ yards (or meters) apart drilled with a slight angle to meet when they are 6+ miles deep.

I'm doubtful that any drilling process can be that straight and accurate unless straight lines are inherent in the drilling process (e.g. lasers somehow). Just think of how much trouble they had drilling to those stranded Chilean miners to rescue them, only 700m down: https://en.wikipedia.org/wiki/2010_Copiap%C3%B3_mining_accid...


That is entirely fair. And per @animats comment it isn't clear they have managed to do anything "new" yet.

That said, microwaves (like lasers) do tend to go straight. So from the point they start using them going forward, I would expect it to be possible (not easy, but possible) to keep them in a straight path.


> That said, microwaves (like lasers) do tend to go straight.

Actually, none of them do. Cutting equipment (even after adapted to drilling) is heavily focused on the near region, usually a few cm away. On distances larger than a few cm, they are no more self-aligning than any mechanical drill.


Great start, but one important factor is missing from this analysis: The surface area (for heat exchange) of a closed-loop borehole is tiny compared to the surface area in a natural hydrothermal system. The walls of the borehole will cool off relatively quickly due to the low thermal conductivity of rock, and you'll soon be unable to make power. Conventional geothermal gets around this by pulling from very large reservoirs that include natural convection and huge fracture surface area.

This means that a closed loop system needs many many many miles of boreholes in order to last long enough to pay off.


You may be right. Back of the envelope kinds of computation though, 6 miles of 12" diameter bore hole is 99,525 sq ft of surface area for thermal transfer. If you think of the lower half of that as the heat injection surface (so 3 miles -> 6 miles and then back up to 3 miles on the way out) call it 100k sqft of rock surface. Now some people have spent a lot of time studying rock (https://pubs.usgs.gov/of/1988/0441/report.pdf) I'm not one of them (more of a casual geologist because I like hiking in the mountains) but if I'm reading the heat transfer equations from pg 91 of that report it still seems like you'd get a decent amount of heat transfer (order of 10's of MJ) into the water.


I'm not sure I understand. Could you point me to a resource that goes into more detail?


Assuming this technology works, it's worth that risk. To be fair, that's a big assumption; most things don't. Meanwhile, already past the point of no return, the inconvenient situation with our climate gets worse while we try to negotiate. This is probably nothing, but it's worth trying.

At the end of this article, there's a bit about the "tech won't save us" crowd. Not saying you're in it, just that it surprises me that such a thing could exist at all. At this point, what the hell else could save us? God, positivity, bans on plastic straws?


Heh, interesting mix of this and the Broken Earth series by NK Jemisin.


They drilled too deep and too greedily.


This is why pushback against climate change policies is, I believe, a healthy thing. Yes, protecting the environment is super important, but time and time again we are told to trust the science, trust the experts, everything is going to go exactly as planned. And time and time again, it turns out the experts didn't account for this, or for that, or were just flat out wrong, and then everyone pays for the "oops".

We see this with everything: social policy, monetary policy, tax policy, etc.

I think a public online resource that documents instances like this, where the experts, or the government, told us X, but it ended up being Y, would be a really powerful tool to fight back against folks who treat science like an infallible religion.


>This is why pushback against climate change policies is, I believe, a healthy thing.

No, it's not. In the past we did next to nothing and we now see the consequences. We may fail if we try, but we are guaranteed to fail if we don't.

And science is like democracy, it's not perfect sometimes even bad, but it's still the best we have. Everything else is worse.


> Yes, protecting the environment is super important, but time and time again we are told to trust the science

What's the alternative? Trust big oil companies instead?


You can't have discovery without taking risks, and you can't generalize one problem to the other problems. Keeping the status quo has its own cost.


> a really powerful tool to fight back against folks who treat science like an infallible religion.

The only tool needed for that is a really simple one: a bumper sticker that says "when you mix science and politics you get politics".

People who can't grok that are not going to come around.




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