I have pretty well established myself as being in the “cautious optimist” column when it comes to the cost and economies of scale that the more tradition “green” tech stack of solar PV, wind, and storage will possess by the end of this decade, and I am at least that pessimistic about nuclear’s potential turn-around.
But enhanced geothermal is very much the outlier… a potential game-changer in which I have a great deal of faith. The fact is that if we get the permitting and policy environment right, it is very much dependent on existing, proven, well-understood technologies which are already cheap, rather than projected to become so. Our ability to effectively execute is virtually assured, compared to moderately probable in the case of renewables+storage and damned unlikely for nuclear.
Probably because Republicans would want to pass some legislation on oil and gas permitting along with geothermal, and Democrats aren't touching that with a 10-foot pole.
Sure, but let’s also realize that if the Democrats proposed harmonizing geothermal drilling rules with those for hydrocarbon exploration, the GOP would oppose it out of knee-jerk factionalism, too.
Today's essay includes this nugget of wisdom: "It turns out, though, that if a large number of people have both the opportunity and the financial incentive to figure something out, they tend to solve the problem." There are, of course, limits to its application. But if politicians, activists and their founders could internalize this simple insight, many problems would move from the "impossible" to the "solvable" column quickly.
I was purposely non-partisan in my framing of which party's "politicians, activists and their founders" would benefit from internalizing the message. The opportunity exists for both.
I really, really, don't know much at all about geology and thermal. So here's my chance to ask a really stupid question:
Would tapping into thermal on a massive scale (as much as we use oil or coal today) have any impact on other aspects of Earth's geology? If we used that much energy could it have any impact on earthquakes, vulcanism, the earth's magnetic sphere or its surface temperature? Or are the scales of those processes a million times greater than the energy we could withdraw?
Geologist here. The scales of those processes you mention are globally much bigger than what we can withdraw.
However, if we drill into shallow, cold rock for geothermal power we can very quickly drawdown what heat is there locally and then make the area unusable for geothermal power. Most of the earth has cold rock at shallow depths, which means that all geothermal power up till now comes from volcanic areas with a magma body at shallow depths (Iceland, Clear Lake CA, Nevada, etc).
Can you scale, for us layfolk, words like “cold,” and perhaps give a timeframe for how long natural processes take to replenish usable levels of heat locally?
Cold pretty much means below the boiling point of water. This is important for geothermal purposes because the boiling point of water changes with pressure, and water is also compressible, so if it expands from pressure loss coming back to the surface it can lose heat.
Here is a map of continental US surface heat flow from underground (units in milliwatts per square meter):
(For context, the deepest oil well ever drilled in the continental US is a 9.5 km well in Oklahoma).
Recharge timescales for hydrothermal systems is hundreds to thousands of years. For hot, dry rock it is hundreds of thousands of years, and for cold, dry rock it is even longer.
Ok, so recharge times are literally geological, makes sense, lol.
How much heat is *stored* in such a system locally enough to be turned to useful work? That is, how long could I run a system from one borehole before it’s tapped out for a few centuries or millennia?
EDIT: Half-assed back of the envelope calculation says that to lower the temperature of a cubic meter of granite from 200C to 100C would yield 34,545 kWh thermal, around 5,180 kWh electrical at current typical efficiency for single-stage geothermal turbines.
That’s… about six months of energy consumption for a typical American household, out of a cubic meter of rock.
What I can’t tell is how quickly the rock not immediately adjacent to a closed-cycle loop would transfer heat towards it, and how long it would take equilibrium temperatures locally to fall below 100C.
I can envision some of the calculus. It’s giving me a headache.
The thermal conductivity of dry, non-porous granite is ~3 W/mK and the thermal diffusivity is ~10^-6 m^2/s. So, if my math is correct, it would take ~200 years for that 1 cubic meter of granite to be heated from 100 C to 200 C via only heat conduction in a low heat flow setting, ignoring fluid flow and radiogenic heat production.
So enhanced, open-loop would seem to be the thing in many locales. The real math on yields for a given field is so far beyond my jet-lagged brain that I’m going to call it a day there, though.
It seems that at a depth of4.5-5.5km, most of the continent is above your definition of ‘cold’. How quickly would one exhaust the useful energy transfer at 100-125 C?
It's pretty hard to extract useful mechanical energy (and thus spin a generator) from heat sources at these temperatures.
The following paper suggests that current Rankine cycle turbines (a special type of heat engine using low boiling point liquids to maximise efficiency for this type of low-grade heat) have a thermal efficiency of about 6% when using heat sources at ~100C.
Those kind of margins also mean that your power production is going to take a huge hit on a hot day.
The problem is at the pressures at 5 km depth the boiling point of water is greater than 300 C. It is a problem because steam is needed to run generators. All we would be returning from 5 km depth across much of the country is mostly hot water, not steam.
Boise brag time: it's had a geothermal system in and near its downtown that dates back over a century. It's been aggressive in expanding it in recent decades, particularly to the campus of Boise State. I'm all for anything that'll make it easier to harness this form of energy.
One winter I stayed at the Breitenbush hot springs - you could soak of course, (you could even "take the waters" since it was developed in the early 20th c) but it was really cool that little cabins also steam-heated thermally via radiators.
While I agree that it's a no-brainer to allow geothermal wells to be drilled under comparable rules to oil and gas, I wouldn't be so quick to assume that hot dry rock geothermal is going to work. An Australian company, Geodynamics, spent half a billion dollars drilling wells in the Australian desert back in the 2000s and 2010s with little success (I lost a few token dollars investing in it):
Yes, technology marches on. The resource is still there (and the rocks are indeed very toasty hot), but nobody has shown any interest in having another go at extracting it. All the money (maybe not the smart money, but the large amounts of money nevertheless) is going into solar and wind backed by batteries, pumped hydro and possibly hydrogen.
Not a silver bullet, buyer beware, etc. etc. but recent stuff happening in geothermal looks very interesting.
In one of the more recent volts podcasts, Dave Roberts talks to a phd doing work on enhanced geothermal. His research shows it's possible that geothermal can act as both power and storage, which makes it very promising costwise.
In a geothermal system, there are three steps:
1. pump cool water into the earth past a bunch of hot rocks
2. take out the heated water (now steam) and turn a turbine to generate electricity
3. take the cooled water, and use it in step 1
But we can actually pump cool water in without simultaneously taking the heated water out. Which means that when we do take the heated water out, it's now hotter, and also under higher pressure. This means that geothermal could neatly complement the intermittent green sources like solar or wind.
Alas, for the most part, physics says no. It has nothing to do with drilling technology even presuming we could ever drill to such depths. It has everything to do with the thermodynamics of solids and pesky unalterable things like thermal conductivity and thermal gradients.
Rock is an excellent insulator. This is a good thing because if it wasn't the surface of this planet would still be molten and life would be somewhat harder. Your diagram for EGS is telling. Are you tapping into virtually unlimited energy? Why no, you are not. You are cooling rock. If you are extracting heat then what you are producing is an ever expanding mass of cooled rock. From which you very shortly will be able to extract no heat at all. Since this rock is an excellent insulator you will be waiting a very long time before the rock reheats to the point where you can extract more heat. And the only way this works is if you have a very large mass of very hot, near molten, to reheat your cooled rock.
This is why we make boilers for thermal generation out of metals which have high thermal conductivity and thin walled boiler tubes at that. It's all about heat transfer. In essence Geothermal can be made to work only where a high heat gradient exists, very hot rock, that can be used to establish a more or less steady state with the heat being extracted. Like Iceland. There are very few such places in the world. By all means, use them.
When it comes to deep drilling that could possibly expand the number of areas where high thermal gradients could be found. But I doubt it would do so by much. As regards drilling technology I would observe that drill bits are the least of your problems. (Diamond drills have been around longer than I have been alive and I am old.) The deeper you go the higher the pressure. That applies to the l column. of drilling fluid. Currently your average frack pump runs about 10 kpsi. But you can buy pumps capable of 20 kpsi. No technology exists, including pumps and well casing that could possible withstand the pressures required to frack at the depths proposed. No hoses. No piping. I can't even imagine what the well casing that needs to be pressurized would look like.
I see no problem with exploring the possibilities but I wouldn't be too sanguine about spectacular results.
Thanks, I have been wondering about rate at which geothermal heat is replenished versus the rate at which it would be extracted in such a system ever since learning about the London Central Line's problem with "imported" heat: https://en.wikipedia.org/wiki/London_Underground_cooling
If we can drill deep enough (20km+), location truly does become “anywhere on the planet”, including right under existing coal and natural gas plants. Which means the energy production and delivery infrastructure is already nearly 100% in place. This should mean there would be fewer permitting barriers in those cases. It also means we could “drop in” nearly carbon neutral replacements for all current energy production.
Also, if we drill deep enough, we don’t have to do fracturing, we can have a “two pipe” system down a single borehole, likely eliminating any earthquake risk.
The key is developing the advanced “drilling” techniques to get to those depths. This will likely not be actual drill bits, but rather directed energy. I am personally excited by MIT spinoff Quaise Energy’s (https://www.quaise.energy) millimeter wave drilling. If it works out, this could be the geothermal energy advancement that actually had a chance of getting us close t carbon neutral by 2050.
So...we strike a Grand Energy Bargain by converting all oil-drilling into water-drilling, and fossil fuel companies become water fuel companies? Sounds great, bring on the non-intermittent energy abundance via Giga Drill Breaker.
Except I doubt it'd happen that serendipitously, since there's that pernicious desire to punish the moral misdeeds of Big Oil(tm), and letting them pivot via a technological redemption arc just wouldn't be a satisfying conclusion. Which is truly a shame. It's almost like no one understands the political value of opportunities to let someone save face anymore...affective polarization is a poor substitute for material living standards improvement. It's not like those oil dollars are gonna just disappear, we may as well try and get them directed towards more productive future uses. Already tried this failure mode before with Big Tobacco(tm) and vaping, and...well...yeah.
I also wonder if there'd be equivalent risks of liquefaction sinkholes and localized earthquakes with geothermal drilling...unless I misunderstand the graphic, it looks a lot like oil fracking? That's a very relevant Schelling point for opposition to rally around. You can just hear the soundbites: "Radical Environmentalists Want To Use Unproven Technology To Create Yellowstone Geysers Under YOUR Community!", "Reckless Fault-Loving Hippies From California Want To Export Earthquake Risks Nationwide!", and probably some Freudian left-opposition comparing drilling of any kind to savage domination of Mother Earth-Goddess. The crimes-against-nature costs of solar, by contrast, happen almost entirely out-of-sight-out-of-mind. Even wind and hydro...a much smaller subset of people get super riled up about bird and salmon deaths, if the payoff is morally righteous electricity.
(There's also surely room for a shitty galaxy-brain take about how "artificially" cooling the Earth's core via constant basting will have Dire Consequences in the unspecified future...)
"There's also surely room for a shitty galaxy-brain take about how "artificially" cooling the Earth's core via constant basting will have Dire Consequences in the unspecified future..." <===Balrogs hate air conditioning
I'll admit to cheaply exaggerated hyperbole for levity, but don't think it's really that far out of line with the myopia one might expect to see from, e.g. the Sunrise Movement. Matt's written about them before, and I think it's a fairly generalizable point about the more-activist fringes of Team Green: https://www.slowboring.com/p/sunrise-movement
(alternatively: remember the whole hullabaloo over Keystone XL? or Bear's Ears?)
At some point I stopped being able to tell whether my irl most-lefty friend was being ironic in worshipping Saint Greta Thunberg, First of Her Name (Greta Fohn). The very strong language they use to try and persuade me of The Nefarious Lie About Plastics is...well...suggestive. It rhymes with that joking-not-joking call to drag all landlords to the guillotines. Crimes against humanity, scum of the earth, justice, something something evils of capitalism. Such attitudes really aren't hard to find in SF. No straw hippies needed, I can guarantee you that at least.
Presuming you're talking about the first sentence of the second paragraph (the third paragraph is about conservatives, not hippies), there are people who appear to be unironically arguing that oil executives should be tried for crimes against humanity and making IG Farben analogies. (See, e.g., https://bigthink.com/the-present/oil-climate-trial/ )
Thank you for sharing the links to eavor. I'm curious how different this really is from fracking though. I know the drilling of long straight cylinders is more appealing than shattering rocks into tiny pieces, but don't they ultimately cause a lot of the same issues with earthquakes etc?
Genuine question, I could be very wrong. But when I watched their videos you linked in your other comment, my first thought was "this is basically fracking"
Yes on permitting reform. But let's be careful about all those pipelines and power lines - people don't like having them on their land when they are forced to accept them by eminent domain (a frequent "reform" that wind and solar advocates propose). Utilities' use of eminent domain - whether for a gas pipeline or a renewable-serving high tension line - is very often a huge negative for rural landowners in particular. One example from personal experience: my wife's family's ranch in western Texas had an easement taken via eminent domain by LCRA (a public utility whose fame when I was in law school in the 1980s was for strip mining and burning lignite - a low grade coal - in a particularly environmentally destructive way but which has now embraced wind power in the Texas Panhandle and so needed power lines to get the energy from there to Austin). LCRA took the easement by eminent domain, and have proved to be - as we feared - dreadful cotenants of the land with us. Florida Power and Light, which doesn't have eminent domain power in Texas, build a power line parallel to LCRA's through voluntary purchases and, among other things, paid the landowners involved multiple times what LCRA paid. Plus the FPL easement's non-monetary terms are much better for the landowners. (If anyone is interested more details on this point, I cowrote an article about the problem of being an "involuntary cotenant" with our lawyers which you can find here - https://scholarship.law.tamu.edu/facscholar/157/ ). I also highly recommend Robert Bryce's PowerHungry podcast (https://robertbryce.com/power-hungry-podcast/ ) and books and writings generally on energy - he knows a lot and writes clearly. Plus he's got great photos of birds (he's a birdwatcher) on his blog.
I do feel compelled to point out that I have near certainty that this LCRA eminent domain line was taken under state law, using state procedures. So, to the extent it’s a general worry about eminent domain as a concept sure, but it didn’t use Federal authorities so the ire there should be directed at state government/ERCOT.
And, yes, rural people don’t like eminent domain and things going across their land. In many ways, that’s the problem we’re trying to solve - how to get power to dense places, which necessarily involves bringing power there somehow, whether via pipeline, power line, or rail/road.
Yes, state law was used - thanks for the clarification. That's where most of the eminent domain action is. The Feds do some limited eminent domain as well and renewable advocates are trying to expand that authority in the name of permitting reform to speed things up. The FPL example shows it is possible to site power lines - in this case from the same point A to the same point B - without eminent domain and with greater respect for the land and landowners' rights.
As with fracking, the injection of water into deep rock puts pressure on already-existing faults. These faults are all going to move some day, but the increased pressure from the water makes them move sooner.
My understanding from David Roberts' interview on EGS with Wilson Ricks (https://www.volts.wtf/p/the-extraordinary-potential-value#details) is that EGS costs would have to come down about 90% in order to be competitive with other renewable sources, although it's so far from being commercial that actual industrial cost estimates are pretty much guesswork.
And given that a lot of the technology is pretty mature (it's basically fracking), it's hard to see this kind of solar energy-type learning curve.
Bottom line is that EGS might not be competitive as a baseload electricity source but could be an excellent replacement for natural gas in providing dispatchable electricity, to cover peaks in demand and other times when solar/wind/etc aren't available.
The European Commission thinks that US fracking costs per unit of energy decreased by roughly 25% in the five years beginning in 2012. However, regional variations were huge, costs increased slightly in some fields and decreased massively in others.
There's amazing potential in networked geothermal run as a utility to replace existing natural gas infrastructure. HEET has done great work in this space: https://heet.org/geogrid/ and there's currently pilots going on with some Massachusetts Utilities.
I have pretty well established myself as being in the “cautious optimist” column when it comes to the cost and economies of scale that the more tradition “green” tech stack of solar PV, wind, and storage will possess by the end of this decade, and I am at least that pessimistic about nuclear’s potential turn-around.
But enhanced geothermal is very much the outlier… a potential game-changer in which I have a great deal of faith. The fact is that if we get the permitting and policy environment right, it is very much dependent on existing, proven, well-understood technologies which are already cheap, rather than projected to become so. Our ability to effectively execute is virtually assured, compared to moderately probable in the case of renewables+storage and damned unlikely for nuclear.
So what’s holding it back? You’d think there’d be some lobby group demanding the permitting be fixed?
Probably because Republicans would want to pass some legislation on oil and gas permitting along with geothermal, and Democrats aren't touching that with a 10-foot pole.
Sure, but let’s also realize that if the Democrats proposed harmonizing geothermal drilling rules with those for hydrocarbon exploration, the GOP would oppose it out of knee-jerk factionalism, too.
I mean, yeah...
Matt's working on that with this column!
Today's essay includes this nugget of wisdom: "It turns out, though, that if a large number of people have both the opportunity and the financial incentive to figure something out, they tend to solve the problem." There are, of course, limits to its application. But if politicians, activists and their founders could internalize this simple insight, many problems would move from the "impossible" to the "solvable" column quickly.
This used to be a conservative chestnut before "conservatives" turned themselves into right wing populists.
I was purposely non-partisan in my framing of which party's "politicians, activists and their founders" would benefit from internalizing the message. The opportunity exists for both.
I agree. But it is a problem when a party has to have its own internal loyal opposition.
I really, really, don't know much at all about geology and thermal. So here's my chance to ask a really stupid question:
Would tapping into thermal on a massive scale (as much as we use oil or coal today) have any impact on other aspects of Earth's geology? If we used that much energy could it have any impact on earthquakes, vulcanism, the earth's magnetic sphere or its surface temperature? Or are the scales of those processes a million times greater than the energy we could withdraw?
Geologist here. The scales of those processes you mention are globally much bigger than what we can withdraw.
However, if we drill into shallow, cold rock for geothermal power we can very quickly drawdown what heat is there locally and then make the area unusable for geothermal power. Most of the earth has cold rock at shallow depths, which means that all geothermal power up till now comes from volcanic areas with a magma body at shallow depths (Iceland, Clear Lake CA, Nevada, etc).
Can you scale, for us layfolk, words like “cold,” and perhaps give a timeframe for how long natural processes take to replenish usable levels of heat locally?
Cold pretty much means below the boiling point of water. This is important for geothermal purposes because the boiling point of water changes with pressure, and water is also compressible, so if it expands from pressure loss coming back to the surface it can lose heat.
Here is a map of continental US surface heat flow from underground (units in milliwatts per square meter):
https://www.smu.edu/-/media/Site/Dedman/Academics/Programs/Geothermal-Lab/Graphics/SMUHeatFlowMap2011_CopyrightVA0001377160_jpg.jpg
And here is a link with maps of continental US subsurface temperatures at various depths:
https://www.smu.edu/Dedman/Academics/Departments/Earth-Sciences/Research/GeothermalLab/DataMaps/TemperatureMaps
(For context, the deepest oil well ever drilled in the continental US is a 9.5 km well in Oklahoma).
Recharge timescales for hydrothermal systems is hundreds to thousands of years. For hot, dry rock it is hundreds of thousands of years, and for cold, dry rock it is even longer.
Ok, so recharge times are literally geological, makes sense, lol.
How much heat is *stored* in such a system locally enough to be turned to useful work? That is, how long could I run a system from one borehole before it’s tapped out for a few centuries or millennia?
EDIT: Half-assed back of the envelope calculation says that to lower the temperature of a cubic meter of granite from 200C to 100C would yield 34,545 kWh thermal, around 5,180 kWh electrical at current typical efficiency for single-stage geothermal turbines.
That’s… about six months of energy consumption for a typical American household, out of a cubic meter of rock.
What I can’t tell is how quickly the rock not immediately adjacent to a closed-cycle loop would transfer heat towards it, and how long it would take equilibrium temperatures locally to fall below 100C.
I can envision some of the calculus. It’s giving me a headache.
The thermal conductivity of dry, non-porous granite is ~3 W/mK and the thermal diffusivity is ~10^-6 m^2/s. So, if my math is correct, it would take ~200 years for that 1 cubic meter of granite to be heated from 100 C to 200 C via only heat conduction in a low heat flow setting, ignoring fluid flow and radiogenic heat production.
So enhanced, open-loop would seem to be the thing in many locales. The real math on yields for a given field is so far beyond my jet-lagged brain that I’m going to call it a day there, though.
It seems that at a depth of4.5-5.5km, most of the continent is above your definition of ‘cold’. How quickly would one exhaust the useful energy transfer at 100-125 C?
It's pretty hard to extract useful mechanical energy (and thus spin a generator) from heat sources at these temperatures.
The following paper suggests that current Rankine cycle turbines (a special type of heat engine using low boiling point liquids to maximise efficiency for this type of low-grade heat) have a thermal efficiency of about 6% when using heat sources at ~100C.
Those kind of margins also mean that your power production is going to take a huge hit on a hot day.
https://mdpi-res.com/d_attachment/sustainability/sustainability-12-10475/article_deploy/sustainability-12-10475.pdf
The problem is at the pressures at 5 km depth the boiling point of water is greater than 300 C. It is a problem because steam is needed to run generators. All we would be returning from 5 km depth across much of the country is mostly hot water, not steam.
You can get around that by using some other working fluid (see comment on Rankine Cycle turbines). But the efficiency is very poor.
I had the same thought. For me, this article is evoking memories of The Core (2003).
Boise brag time: it's had a geothermal system in and near its downtown that dates back over a century. It's been aggressive in expanding it in recent decades, particularly to the campus of Boise State. I'm all for anything that'll make it easier to harness this form of energy.
One winter I stayed at the Breitenbush hot springs - you could soak of course, (you could even "take the waters" since it was developed in the early 20th c) but it was really cool that little cabins also steam-heated thermally via radiators.
While I agree that it's a no-brainer to allow geothermal wells to be drilled under comparable rules to oil and gas, I wouldn't be so quick to assume that hot dry rock geothermal is going to work. An Australian company, Geodynamics, spent half a billion dollars drilling wells in the Australian desert back in the 2000s and 2010s with little success (I lost a few token dollars investing in it):
https://www.ga.gov.au/ausgeonews/ausgeonews201306/geothermal.jsp
Yes, technology marches on. The resource is still there (and the rocks are indeed very toasty hot), but nobody has shown any interest in having another go at extracting it. All the money (maybe not the smart money, but the large amounts of money nevertheless) is going into solar and wind backed by batteries, pumped hydro and possibly hydrogen.
These folks have a closed loop geothermal that is deploying systems now: https://www.eavor.com/
There are several videos on Youtube talking about current projects, including this one.
https://www.youtube.com/watch?v=ypDQ4t_lIMo
Not a silver bullet, buyer beware, etc. etc. but recent stuff happening in geothermal looks very interesting.
In one of the more recent volts podcasts, Dave Roberts talks to a phd doing work on enhanced geothermal. His research shows it's possible that geothermal can act as both power and storage, which makes it very promising costwise.
In a geothermal system, there are three steps:
1. pump cool water into the earth past a bunch of hot rocks
2. take out the heated water (now steam) and turn a turbine to generate electricity
3. take the cooled water, and use it in step 1
But we can actually pump cool water in without simultaneously taking the heated water out. Which means that when we do take the heated water out, it's now hotter, and also under higher pressure. This means that geothermal could neatly complement the intermittent green sources like solar or wind.
https://www.volts.wtf/p/the-extraordinary-potential-value
Alas, for the most part, physics says no. It has nothing to do with drilling technology even presuming we could ever drill to such depths. It has everything to do with the thermodynamics of solids and pesky unalterable things like thermal conductivity and thermal gradients.
Rock is an excellent insulator. This is a good thing because if it wasn't the surface of this planet would still be molten and life would be somewhat harder. Your diagram for EGS is telling. Are you tapping into virtually unlimited energy? Why no, you are not. You are cooling rock. If you are extracting heat then what you are producing is an ever expanding mass of cooled rock. From which you very shortly will be able to extract no heat at all. Since this rock is an excellent insulator you will be waiting a very long time before the rock reheats to the point where you can extract more heat. And the only way this works is if you have a very large mass of very hot, near molten, to reheat your cooled rock.
This is why we make boilers for thermal generation out of metals which have high thermal conductivity and thin walled boiler tubes at that. It's all about heat transfer. In essence Geothermal can be made to work only where a high heat gradient exists, very hot rock, that can be used to establish a more or less steady state with the heat being extracted. Like Iceland. There are very few such places in the world. By all means, use them.
When it comes to deep drilling that could possibly expand the number of areas where high thermal gradients could be found. But I doubt it would do so by much. As regards drilling technology I would observe that drill bits are the least of your problems. (Diamond drills have been around longer than I have been alive and I am old.) The deeper you go the higher the pressure. That applies to the l column. of drilling fluid. Currently your average frack pump runs about 10 kpsi. But you can buy pumps capable of 20 kpsi. No technology exists, including pumps and well casing that could possible withstand the pressures required to frack at the depths proposed. No hoses. No piping. I can't even imagine what the well casing that needs to be pressurized would look like.
I see no problem with exploring the possibilities but I wouldn't be too sanguine about spectacular results.
Thanks, I have been wondering about rate at which geothermal heat is replenished versus the rate at which it would be extracted in such a system ever since learning about the London Central Line's problem with "imported" heat: https://en.wikipedia.org/wiki/London_Underground_cooling
If we can drill deep enough (20km+), location truly does become “anywhere on the planet”, including right under existing coal and natural gas plants. Which means the energy production and delivery infrastructure is already nearly 100% in place. This should mean there would be fewer permitting barriers in those cases. It also means we could “drop in” nearly carbon neutral replacements for all current energy production.
Also, if we drill deep enough, we don’t have to do fracturing, we can have a “two pipe” system down a single borehole, likely eliminating any earthquake risk.
The key is developing the advanced “drilling” techniques to get to those depths. This will likely not be actual drill bits, but rather directed energy. I am personally excited by MIT spinoff Quaise Energy’s (https://www.quaise.energy) millimeter wave drilling. If it works out, this could be the geothermal energy advancement that actually had a chance of getting us close t carbon neutral by 2050.
Lots of interesting stuff happening in this space.
So...we strike a Grand Energy Bargain by converting all oil-drilling into water-drilling, and fossil fuel companies become water fuel companies? Sounds great, bring on the non-intermittent energy abundance via Giga Drill Breaker.
Except I doubt it'd happen that serendipitously, since there's that pernicious desire to punish the moral misdeeds of Big Oil(tm), and letting them pivot via a technological redemption arc just wouldn't be a satisfying conclusion. Which is truly a shame. It's almost like no one understands the political value of opportunities to let someone save face anymore...affective polarization is a poor substitute for material living standards improvement. It's not like those oil dollars are gonna just disappear, we may as well try and get them directed towards more productive future uses. Already tried this failure mode before with Big Tobacco(tm) and vaping, and...well...yeah.
I also wonder if there'd be equivalent risks of liquefaction sinkholes and localized earthquakes with geothermal drilling...unless I misunderstand the graphic, it looks a lot like oil fracking? That's a very relevant Schelling point for opposition to rally around. You can just hear the soundbites: "Radical Environmentalists Want To Use Unproven Technology To Create Yellowstone Geysers Under YOUR Community!", "Reckless Fault-Loving Hippies From California Want To Export Earthquake Risks Nationwide!", and probably some Freudian left-opposition comparing drilling of any kind to savage domination of Mother Earth-Goddess. The crimes-against-nature costs of solar, by contrast, happen almost entirely out-of-sight-out-of-mind. Even wind and hydro...a much smaller subset of people get super riled up about bird and salmon deaths, if the payoff is morally righteous electricity.
(There's also surely room for a shitty galaxy-brain take about how "artificially" cooling the Earth's core via constant basting will have Dire Consequences in the unspecified future...)
"There's also surely room for a shitty galaxy-brain take about how "artificially" cooling the Earth's core via constant basting will have Dire Consequences in the unspecified future..." <===Balrogs hate air conditioning
Look, I'm not saying "No" to geothermal energy, I'm just saying we shouldn't delve too greedily and too deep . . . .
Or if we do, just dump off some nuclear waste at the same time. Depleted-U shall not pass.
Are there existing people with these objections or are you making up a hippy to punch?
I'll admit to cheaply exaggerated hyperbole for levity, but don't think it's really that far out of line with the myopia one might expect to see from, e.g. the Sunrise Movement. Matt's written about them before, and I think it's a fairly generalizable point about the more-activist fringes of Team Green: https://www.slowboring.com/p/sunrise-movement
(alternatively: remember the whole hullabaloo over Keystone XL? or Bear's Ears?)
At some point I stopped being able to tell whether my irl most-lefty friend was being ironic in worshipping Saint Greta Thunberg, First of Her Name (Greta Fohn). The very strong language they use to try and persuade me of The Nefarious Lie About Plastics is...well...suggestive. It rhymes with that joking-not-joking call to drag all landlords to the guillotines. Crimes against humanity, scum of the earth, justice, something something evils of capitalism. Such attitudes really aren't hard to find in SF. No straw hippies needed, I can guarantee you that at least.
Presuming you're talking about the first sentence of the second paragraph (the third paragraph is about conservatives, not hippies), there are people who appear to be unironically arguing that oil executives should be tried for crimes against humanity and making IG Farben analogies. (See, e.g., https://bigthink.com/the-present/oil-climate-trial/ )
Matt's example is open loop geothermal which does look like oil fracking. Closed loop looks quite different. https://www.eavor.com/
Thank you for sharing the links to eavor. I'm curious how different this really is from fracking though. I know the drilling of long straight cylinders is more appealing than shattering rocks into tiny pieces, but don't they ultimately cause a lot of the same issues with earthquakes etc?
Genuine question, I could be very wrong. But when I watched their videos you linked in your other comment, my first thought was "this is basically fracking"
Yes on permitting reform. But let's be careful about all those pipelines and power lines - people don't like having them on their land when they are forced to accept them by eminent domain (a frequent "reform" that wind and solar advocates propose). Utilities' use of eminent domain - whether for a gas pipeline or a renewable-serving high tension line - is very often a huge negative for rural landowners in particular. One example from personal experience: my wife's family's ranch in western Texas had an easement taken via eminent domain by LCRA (a public utility whose fame when I was in law school in the 1980s was for strip mining and burning lignite - a low grade coal - in a particularly environmentally destructive way but which has now embraced wind power in the Texas Panhandle and so needed power lines to get the energy from there to Austin). LCRA took the easement by eminent domain, and have proved to be - as we feared - dreadful cotenants of the land with us. Florida Power and Light, which doesn't have eminent domain power in Texas, build a power line parallel to LCRA's through voluntary purchases and, among other things, paid the landowners involved multiple times what LCRA paid. Plus the FPL easement's non-monetary terms are much better for the landowners. (If anyone is interested more details on this point, I cowrote an article about the problem of being an "involuntary cotenant" with our lawyers which you can find here - https://scholarship.law.tamu.edu/facscholar/157/ ). I also highly recommend Robert Bryce's PowerHungry podcast (https://robertbryce.com/power-hungry-podcast/ ) and books and writings generally on energy - he knows a lot and writes clearly. Plus he's got great photos of birds (he's a birdwatcher) on his blog.
And - I almost forgot to mention the great Australian film, The Castle (not the US one with Robert Redford), about eminent domain. Very well done and clever, with a superb cast. https://en.wikipedia.org/wiki/The_Castle_(1997_Australian_film)
I do feel compelled to point out that I have near certainty that this LCRA eminent domain line was taken under state law, using state procedures. So, to the extent it’s a general worry about eminent domain as a concept sure, but it didn’t use Federal authorities so the ire there should be directed at state government/ERCOT.
And, yes, rural people don’t like eminent domain and things going across their land. In many ways, that’s the problem we’re trying to solve - how to get power to dense places, which necessarily involves bringing power there somehow, whether via pipeline, power line, or rail/road.
Yes, state law was used - thanks for the clarification. That's where most of the eminent domain action is. The Feds do some limited eminent domain as well and renewable advocates are trying to expand that authority in the name of permitting reform to speed things up. The FPL example shows it is possible to site power lines - in this case from the same point A to the same point B - without eminent domain and with greater respect for the land and landowners' rights.
I thought the big issue with geothermal drilling was the earthquakes. Have they figured this out yet?
https://www.wired.co.uk/article/swiss-rock-lab
As with fracking, the injection of water into deep rock puts pressure on already-existing faults. These faults are all going to move some day, but the increased pressure from the water makes them move sooner.
Austin Vernon's blog has some interesting articles looking into the cost effectiveness of different approaches to geothermal:
https://austinvernon.site/blog/geothermal.html
https://austinvernon.site/blog/drillingplan.html
https://austinvernon.site/blog/geothermalnextsteps.html
My understanding from David Roberts' interview on EGS with Wilson Ricks (https://www.volts.wtf/p/the-extraordinary-potential-value#details) is that EGS costs would have to come down about 90% in order to be competitive with other renewable sources, although it's so far from being commercial that actual industrial cost estimates are pretty much guesswork.
And given that a lot of the technology is pretty mature (it's basically fracking), it's hard to see this kind of solar energy-type learning curve.
Bottom line is that EGS might not be competitive as a baseload electricity source but could be an excellent replacement for natural gas in providing dispatchable electricity, to cover peaks in demand and other times when solar/wind/etc aren't available.
If geothermal gets good enough, we could have Blue Lagoons everywhere! That resort runs off of waste water from a geothermal plant.
We need permitting reform for…just about everything.
My question is always “will it work?” One can venture a decent answer with two data points:
1) How much has the cost of sinking a deep oil well decreased in the last 30 years?
2) Would geothermal energy be competitive with nuclear if its cost decreased by the same factor as deep oil drilling over the last 30 years?
We don’t know that geothermal costs would fall exactly as quickly as drilling costs, but it would be a good reality check.
Does anyone have the data to plug into my little model?
The European Commission thinks that US fracking costs per unit of energy decreased by roughly 25% in the five years beginning in 2012. However, regional variations were huge, costs increased slightly in some fields and decreased massively in others.
http://www.insightenergy.org/system/publication_files/files/000/000/067/original/RREB_Shale_Gas_final_20170315_published.pdf?1494419889
There's amazing potential in networked geothermal run as a utility to replace existing natural gas infrastructure. HEET has done great work in this space: https://heet.org/geogrid/ and there's currently pilots going on with some Massachusetts Utilities.