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.
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 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?
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.
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.
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.
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...)
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.
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.
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.
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 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?
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.
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.
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.
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...)
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 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
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?
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.