Geothermal energy could outperform nuclear power
economist.com
economist.com
I’m skeptical that geothermal will ever make a significant impact in the US. Though it might make a difference in much farther north places, where solar struggles.
https://www.eia.gov/electricity/data/browser
https://www.eia.gov/totalenergy/data/browser/?tbl=T01.02#/?f...
Based on breakthrough fusion research and well-established drilling practices, we are developing a radical new approach to ultra-deep drilling."
This company looks promising in the geothermal space. They are looking to be able to create 10km boreholes in 100 days. This would make geothermal viable anywhere in the world. Bonus points if you create the borehole next to an existing coal plant to use the existing turbine and infrastructure.
https://www.bhauth.com/blog/flawed%20ideas/microwave%20drill...
Per [1], “[wells] with a regular production casing diameter of 200-250 mm have an average capacity of 5.5 MWe”. Quaise has deep bores that could potentially have higher temperatures, but let's stick with 5 MWe.
At the article's 12 MWh/m³ for drilling, and 250mm bores of depth 10km, WolframAlpha tells me that is 6 GWh.
Divide through, you get 1000 hours or about a month. This doesn't match their “significantly over 10 years” they gave before mentioning waveguide losses.
The main difference I suppose is the thermal conductivity comment, where I didn't follow why Quaise wouldn't be able to use enhanced geothermal approaches. More specifically I think that if a Quaise well has ~1% the energy output of a normal geothermal well, it's pretty weird to frame the problem as about the energy cost of drilling, and not the whole factor-100 reduction in energy output.
To be clear, this seemed like an interesting article and I'm not claiming my napkin math is definitive, I really am neither an expert nor someone who has spent a lot of time investigating this. I do think some more clarity on how the math looks would help their case.
[1] https://www.thinkgeoenergy.com/report-success-of-high-temper...
Enhanced geothermal involves fracking. Typical proposals involve creating crack paths between 2 nearby wells by fracking from both. It's been tested some but so far has not been economical.
Apart from the cost issues of enhanced geothermal so far, Quaise plans to drill deeper to higher temperatures to reduce power block costs. Sufficiently hot rock flows a little bit which makes fracking ineffective. Fracking also doesn't work as well with supercritical water. (If not drilling to rock hot enough to flow a little bit under high pressures, it would be much better to use conventional drilling techniques.)
I'm afraid I'm not really following the argument though. I don't have the technical background to judge how economical EGS is or not, I just want to understand this energy-based argument. I checked to be sure, and Quaise's initial plans (per cofounder Matt Houde) are indeed EGS-based[1], just deeper. It seems correct to me that if they succeeded at building wells that way, they would produce at least comparable energy to standard wells.
It's entirely possible that EGS just doesn't work at really deep depths as you state here, but this seems like a qualitatively different argument to the one presented in the article.
[1] https://youtu.be/yz6rRw59Huw?t=675 "but what we're interested in in Quaise is this novel idea here all the way on the right which we call like to call superhot rock EGS systems"
Actually, they address the energy balance question at the end of that talk.
https://youtu.be/yz6rRw59Huw?t=3016 "[...] we could be using around five megawatts for the drilling process to drill our wells, and let's say we use that five megawatts over a year to drill three holes, so we get an injector and two producers. We predict that configuration of the two producers and an injector at superhot conditions can produce something around 50 to 100 megawatts of electrical energy, again owing to the benefits of producing this superhot, supercritical steam."
They also answer a question on borehole stability, admittedly claiming largely that they don't know.
A different argument to the one presented in the article, you say. Huh.
I suppose I can't claim to know more about geothermal than the author of that blog post, but if you check again, you'll find it does mention EGS. Apparently something made the author decide the problems with Quaise using that are non-obvious enough to need explanation.
The article mentions EGS but, as far as I could tell, only seemed to present it to contrast it with the claim that Quaise is using a worse single-bore strategy.
If I'm just misreading, and it sounds like you're saying I am?, it'd be really helpful to show your working so I can see where the models are differing. There is a factor 100 difference somewhere, it shouldn't be that hard to spot!
Some questions:
You say, “if there's enough pressure to make a little crack, then the fluid can instantly expand and immediately make a big crack”. My admittedly quite surface level view of the research is that it is viewed as feasible in this regime.
“Close to the brittle-ductile transition conditions of pressure and temperature, new findings suggest that fractures are sufficiently permeable to allow fluid circulation and, in case of insufficient fracture density, enhancement strategies are likely to be successful”
https://www.nature.com/articles/s41467-019-12146-0
I also believe that EGS fracture enhancement marginally prefers hydro-shearing (crack expansion) rather than hydro-fracking (crack formation), so if creating cracks is problematic, that leaves options open.
I also note that to my understanding gas fracking is already a thing, cf. nitrogen fracking. So gaseous behavior doesn't obviously seem like an instant write-off to me.
I'm sure that isn't convincing to you, but it's a bit challenging for me as a layman wrt. geothermal to see why I should trust your gut here, so to speak, and I'm wondering if you have a concrete argument I can evaluate on merits?
For example,
"The hypothesis that the brittle–ductile transition (BDT) drastically reduces permeability implies that potentially exploitable geothermal resources (permeability >10−16 m2) consisting of supercritical water could occur only in rocks with unusually high transition temperatures such as basalt. However, tensile fracturing is possible even in ductile rocks, and some permeability–depth relations proposed for the continental crust show no drastic permeability reduction at the BDT."
https://www.nature.com/articles/ngeo2879
I'm definitely not claiming to take these on faith, I'm just saying I haven't really been given a reason to believe those arguments are less trustworthy than your claims otherwise.
It's really hard to vapourize all that rock and suck it out to the surface with a vacuum. But it's really hard in the sense that the vaporised rock might recondense and stick to the sides of the hole, not in the sense that vaporising the rock costs more energy than you get out of the hole in its 30-year lifetime.
Skepticism is reasonable around any new technology, but the arguments for geothermal are convincing enough that it seems easily worth the attempt.
I do think geothermal has a part to play, specifically for heating and cooling of neighbourhoods and multifamily developments. The construction has to move a ton of dirt anyway, so might as well install some ground loops while you're at it. If you're forced to drill due to site conditions, the load is lower than pure electricity generation meaning the wells are not that deep. For private homes it's far too expensive to be much more than a curiosity, but amortized across a whole new neighbourhood or collection of apartment buildings it's very affordable. Especially in northern climates accessing the consistent ground heat source/sink that allows you to run heat pumps at max efficiency all year is a huge win and is a huge amount of electricity you never need to generate in the first place.
You may be underestimating the extent of geothermal power production that already exists around the world. For example, California's Geysers[1] and Salton Sea[2] geothermal complexes are some of the largest in the world, generating more electricity than all of Iceland's geothermal power plants combined.
[1] https://en.wikipedia.org/wiki/The_Geysers
[2] https://en.wikipedia.org/wiki/Imperial_Valley_Geothermal_Pro...
I think you underestimate the scale of geothermal available. The US is the largest geothermal power producer in the world though no one thinks of the US as that. Not coincidentally, it also sits on top of the largest high-quality geothermal basin in the world, essentially the entire Mountain West.
The US barely taps these resources at all despite leading the world. Ironically, much of the pushback on developing these geothermal resources in the US comes from environmental activists.
I understand people see this as an underperforming investment but I instead see it as de-risking.
Nuclear fission is the answer.
Today there are 440 nuclear reactors operating in 32 countries.
Nuclear fission is expensive up-front but once built the power plant can last 50 years (maybe 80, maybe more) and the uranium fuel is very cheap, perhaps 10% of the cost of running the plant.
This is in stark contrast to natural gas, where the plant is less expensive to build but then fuel costs accumulate rapidly. And natural gas is a poor choice if you care about greenhouse gas emissions.
Sam Altman owns a stake in Oklo, a small modular reactor company. Bill Gates has a huge stake in his TerraPower nuclear reactor company. Oracle announced that it is designing data centers with small modular nuclear reactors:
https://news.ycombinator.com/item?id=41505514
In China, 5 reactors are being built every year. 11 more were announced a few weeks ago. You just don't hear about it... yet.
Nuclear fission is safe, clean, secure, and reliable.
> The latest results released for Cape Station do not include the fluid loss number, so we don't know if it improved. Options remain even if it didn't, like reducing fluid throughput. That would hurt productivity, but further gains from drilling and completion intensification could compensate.
Th hallmark of a great civilization is one that saves its future self from problems, not one that piles on problems for its future self to deal with. In this light, nuclear is not great.
Geothermal using fracking toxins is not great either if it irreversibly pollutes the water supply as fracking often does.
Solar and wind have no such issues for us to deal with, considering we don't domestically produce the solar panels anyway.
I'll save you the effort, it's about one chicken egg, maybe as large as a tea cup.
For your whole life, all the energy you'll use across all sectors. Over 100 years you don't think we capable of finding a space to safely fritter away a chicken egg? Or even 300 million chicken eggs?
And even more amazingly, that "waste"? It's still fuel, we could reprocess it.
Coal, you'd need 50-60,000 kilograms to create the same energy. The waste disposal for 60k kg of coal's ash is non trivial (and much harder to prevent from spreading). To say nothing of the 150-180,000 kg of CO2 emitted.
Solar panels would need to be replaced 2-5 times in that timeframe. They are a whole lot less wasteful than coal, but that'd still be a significant volume of difficult to reprocess material.
So, before wringing your hands about waste from nuclear, make sure you understand just how small the amount of waste is and think about the waste of alternatives. There's not a free lunch here, but waste just isn't a material concern compared against other power sources.
High level radioactive waste can cause Goiânia like outcomes, or leach into the groundwater.
https://en.wikipedia.org/wiki/Goi%C3%A2nia_accident
It is quite intellectually dishonest to try frame it as pixie dust rather than the true problem it poses.
And I'm just doing my best to present the facts as they are -- no fud.
The US was founded ~250 years ago as a perspective.
Comparing it with coal is 100% disingenuous. Coal is never an option going forward.
You say that as if it's a given that it will always leak slowly. What % of the spent fuel actually ended up being leaked across the couple decades of storage we have had now? What effects did it have? How does the human cost stack up against mining activities we would need for the massive amounts of wind turbines and solar panels when we cut out nuclear's base load function completely?
(Recently saw this documentary about mine tailings aka chat; didn't know those existed tbh as someone not from a country with much mining activity https://www.youtube.com/watch?v=soGOu5NZ5S0 - or in text form https://en.wikipedia.org/wiki/Picher,_Oklahoma)
Obviously we'll need both energy sources to reach net zero, but it's not that one is inherently clean and the other inherently dirty
I prefer to assume we're comparing competent operators of any energy type in our portfolio. Saying it leaches into the groundwater is like saying "dams break and destroy towns". Yeah, it does happen I guess, but not often. And we've got lots of systems to prevent it.
Firstly, the containers are known to develop leaks over decades. Secondly, there are accidents on site every year, causing tritium leaks if not also uranium. There is also a baseline level of tritium leakage that's considered normal, but it isn't actually normal for the fishes in the river.
> I prefer to assume we're comparing competent operators
Please see the list of leakage incidents at each nuclear power plant. There is one almost every year at almost every site. The local environment pays the price for it. If they were competent, these events wouldn't happen.
None of this is an issue with solar, for example. The radius of the possible damage is minuscule.
Come back when it is in the same league as renewables or CCGTs.
Solar was expensive until we started building a lot of it (often due to heavy subsidisation)
When the need for the insurance subsidy is removed then we can talk about it being as safe.
https://en.wikipedia.org/wiki/Price%E2%80%93Anderson_Nuclear...
Comparatively solar sits at 5.5% today but is rapidly increasing.
If 18% of the global electricity mix is not trying hard enough then the technology did not work out.
The cost savings never materialized, it’s always been a case of negative learning by doing.
https://www.sciencedirect.com/science/article/abs/pii/S03014...
Meaning, with your own logic the French nuclear buildout was impossible since no one had done it before.
It was possible. Just like renewables are today.
Given the differences in cost investing nuclear power today prolongs our fight against climate change.
For every dollar invested in nuclear power we get less effect and need to wait longer for the effect to materialize compared to renewables.
https://www.lazard.com/media/xemfey0k/lazards-lcoeplus-june-...
Now the battery revolution has begun and gas is being forced off the grids.
https://theprogressplaybook.com/2024/06/20/gas-power-output-...
We also need to understand that we are not aiming for perfection. We are aiming for good enough.
If the emergency reserve for the extremely cold winter week in 2040 is fossil fuels that is good enough. We are talking 1% of our total consumption.
As long as we can force it to transition to efuels or be replaced when those are the most pressing issues still to tackle.
> A combined cycle power plant is an assembly of heat engines that work in tandem from the same source of heat, converting it into mechanical energy. On land, when used to make electricity the most common type is called a combined cycle gas turbine plant (https://en.wikipedia.org/wiki/Combined_cycle_power_plant)
https://reneweconomy.com.au/a-near-100-per-cent-renewable-gr...
Nuclear is the biggest boondogle in electric generation history. And a huge fraction of that bloated cost is still hidden in externalities, as the overwhelming majority of all spent fuel is still sitting in "temporary" storage onsite with the reactor where it was used.
Geothermal aside, using money to increase grid storage is a vastly better investment than nuclear can ever be.
None of this spent fuel is really that spent, has plenty of other use cases, and should be used. Also, storing it in concrete casks for 40 years is perfectly safe and has caused 0 harm.
The cost is largely due to regulatory hurdles that are slowly being eroded.
The problem is that you need to keep it for thousands of years before it becomes tractable to more easily deal with it.