If it lives up to its promise, one emergent technology could take coal and gas off-line in very few years, and produce all of the clean electricity we could ever need anywhere on the planet essentially forever.
High-temperature geothermal energy has always had a series of related problems: it is very expensive to drill deep enough to reach hot rock, you can only affordably drill so deep, and all too often you don’t hit hot rock, so the money you spent boring that hole is wasted. Between the expense of drilling deep, and the limitations of steel and the other materials used to build rotary rock drills, you can only get down to rock that’s 300 or 350 °C. At those low temperatures—about like a first-generation nuclear power plant—a geothermal energy station is about as inefficient as a gasoline engine, maybe 20 or 25 percent. And that means it has to be bigger and more expensive for the same output.
High-temperature geothermal energy has always had a series of related problems: it is very expensive to drill deep enough to reach hot rock, you can only affordably drill so deep, and all too often you don’t hit hot rock, so the money you spent boring that hole is wasted. Between the expense of drilling deep, and the limitations of steel and the other materials used to build rotary rock drills, you can only get down to rock that’s 300 or 350 °C. At those low temperatures—about like a first-generation nuclear power plant—a geothermal energy station is about as inefficient as a gasoline engine, maybe 20 or 25 percent. And that means it has to be bigger and more expensive for the same output.
,
Technology developed by Paul Woskov, Senior Research Engineer at MIT’s Plasma Science and Fusion Research Center, being tested right now, will change all of that. Boston-based Quaise Energy, an MIT spin-off, will drill through softer, near-surface sedimentary rock with a conventional rotary drilling rig, then switch to a plasma guide that vaporizes its way through harder igneous “basement” rock with millimeter-wavelength electron beams generated in a device called a gyrotron. Gyrotrons are used to heat plasma for nuclear fusion experiments; they are well-understood, off-the-shelf technology.
Rotary drilling has gone as deep as 7 ½ miles. Russia’s Kola Superdeep Borehole went that deep, but took 20 years to drill (it was a science experiment, not a production well). Quaise thinks they can go 20 km/12 ½ miles deep in as little as 100 days. That deep, the rock is often as hot as 500 °C. Steam that hot should generate power with an efficiency in the low 40 percentile range—you'd need half as much power plant as at 350 °--and do it with the same "off the shelf" equipment and workers used in coal-fired power plants now, easing and speeding the transition to clean, inexhaustible energy awhile maintaining those jobs.
Quaise hopes to drill a 30-foot-deep test bore at Oak Ridge National Laboratory in 2022, a 330-foot deep well in New Mexico next, and, with AltaRock Energy, a 3,300 foot bore at the Newberry Volcano in Central Oregon, where AltaRock hopes to have a demonstration power plant running by 2026. They mean to begin “refiring” coal-fired power plants to geothermal energy in 2028.
Quaise is working with 1 MW gyrotrons because those are already available. They could drill faster with more power; they’re talking about 2 MW, so far, and I read some discussion of 10. You can do 2 MW with a very large diesel generator—or a very small nuclear reactor, which might be the ideal power supply for a rig designed to move from site to site and drill a bunch of wells. The energy beam melts the rock at up to 3,000 °C, “vitrifying” it to line the bore with glass. The excess vaporized/molten rock is blown out of the hole with argon, which is both non-reactive and transparent to millimeter-wavelength frequencies.
"Theoretical Considerations Thermodynamic calculations suggest a penetration rate of 70 meters / hour (230 feet / hour) is possible in 5 cm (1.97 inches) bores with a 1 MW gyrotron that couples to the rock with 100% efficiency. Use of lower or higher powered sources (e.g. 100 kW to 2 MW) would allow changes in bore size and/or penetration rate. "
"Figure 4 shows the relationship of Power, wellbore diameter and rate of penetration (ROP). From this relationship, a 5 cm (1.97 in) diameter wellbore could be penetrated via vaporization only at 50 m/hr (150 ft/ hr) with 1 MW of power. If we consider the Air Force’s 2 MW gyrotron, we could penetrate (with full vaporization) a 15 cm (6”) diameter wellbore at about 10 m/hr (30 ft/ hr) or a Figure 3. Wellbore diameter vs. power density DE-EE0005504 Final Report Impact Technologies LLC Massachusetts Institute of Technology 14 30 cm (12”) bore at 7 m/hr (21 ft/ hr) independent of rock hardness. That same rate could be obtained via only melting using a reduced estimated 700 kW of power. Further, for EGS sizes, a 15” bore could be drilled (with full vaporization) at 80 m/hr (262 ft/hr) with a 10MW gyrotron, or only 2.5 MW if only melted. These ROP estimates would be reduced by the actual MMW absorption efficiency, which is currently estimated at 70%. As noted, they could be increased by not requiring 100% vaporization of all rocks encountered- resulting in utilizing only ¼ to 1/3 of the vaporization energy listed." https://www.osti.gov/servlets/purl/1169951 .
Figure 4 wouldn't copy. But 2 MW gyrotron, 6" wellbore, 30 ft/hr through hard rock; 10 MW, 15" bore, 262 ft/hr. Wow.
Quaise thinks they can drill to supercritical-hot rock anywhere on the planet, including the grounds of any coal plant they wish to convert. They hope to produce energy for 1 to 3 cents per kWh, cheaper than coal—and you don’t have to buy your power plant a train load of coal every day. Apparently a ton of coal went from $36 in Oct. 2021, to $110 in late 2021 to $385 on July 5, 2022 (businessinsider.com/commodities/coal-price). At ~$385 per ton delivered, if a car carries 116 tons and each train is 115 cars (a large power plant is supposed to burn a train load every day) = $5,135,900 per train load of coal (up from less than $500 k a year ago!?). A train a day would be $1.875 billion a year just for fuel!?
I do wonder about something. Melting/vaporizing the rock, and letting some of it harden into glass lining the bore, sounds like a wonderful way to avoid having to lower steel casings 12 miles down a well shaft, and grout them in. But I wonder how durable it will be in practice? Any movement of the rock strata, as might be induced by fracking the rock, is going to tend to crack or break that glass. It is not going to be homogenous, like manufactured glass: it will be full of impurities and bubbles and stress lines and it sounds like something that will want to crack. Any pockets of water (or hydrocarbons?) will explode, at those temperatures. And changes in temperature, especially rapid changes, will also tend to fracture the glass; all of Paul Woskov's test bores into rock slabs in his laboratory broke, which tends to happen when you heat the middle of something, but not the edges, very hot, very fast. That might not matter, or fixing it might be as simple as adding something like Radiator Stop-Leak to the injection water. And even if these wells do turn out to need steel casings, being able to drill 12 miles deep in 100 days will change the world. But it will be interesting to see how well those vitrified casings hold up.
--- --- ---
Slovakia-based PLASMABITS is exploring similar technology, but so far is talking about drilling 10 km deep, not 20, where temperatures are ~350 °C, not 500, and accessing GE under 70 percent of Earth’s surface, not 90 percent. Supercritical heat is what will make geothermal as efficient and much less expensive than coal. PLASMABITS is also talking about using plasma drilling to explore for—and extract?—deep-rock minerals, and to reduce the time and cost of boring tunnels for subways, hyperloops. … Their logo is GA Drilling, where GA stands for Geothermal Anywhere.
There are more than 8,500 coal-fired power plants around the world, totaling over 2,000 gigawatts of capacity. Geothermal capacity, across 29 countries, is only 15.4 GW. If deep plasma drilling works and we get busy we might transfer that 2 k GW (2 TW, terawatts) from coal to clean geothermal in a decade. If we’re very lucky, that might actually be soon enough. See Post No. 1 on methane excursions.
It’s still far easier to get a permit to drill for oil/gas on public lands than it is a geothermal well.
------------
There is a discouraging, undated report by the U.S. DOE Office of Fossil Energy and Carbon Management [i] detailing their goal of making coal-fired power generation cleaner and more efficient (from 33 percent average at present into the low 40s) by 2040 or thereabouts. Some people just don’t get it. We need to stop burning coal, right now, or the future has no future. DOE would be much better advised to spend its taxpayer money on deep geothermal, or molten-salt nukes, or anything but coal. Is this what happens when government agencies get captured by the industries they are supposed to regulate?
https://www.energy.gov/fecm/science-innovation/office-clean-coal-and-carbon-management/advanced-energy-systems/transformative
Quaise had raised $63 million as of Feb. 2022.
"A supercritical power plant can be 4 to 10 times as efficient as subcritical. At 400 °C, ten times the energy as at 200 °C"!? That’s not what I see investigating nukes; twice the temperature means twice the pressure and only half again the power output. Still, "they" say that super-deep geothermal could produce power less expensively than on-shore wind. At 500 °C, off-the-shelf supercritical coal-plant equipment works fine. and the supply lines, repair parts and manufacturing capability is already there, as are a whole bunch of already-built power plants that only need their fuels switched.
“Temperatures at 20 km depth are above the supercritical point of water, which allows ten times more energy to be transferred given the same volumetric flow.[6]” Wikipedia, Quaise. ???? I don't think that's right. Wish it was ... .
---------
References
Jack Dunhill, “Company Plans To Drill 20 Kilometers Into Earth To Tap "Virtually Unlimited" Energy,” IFL Science, Mar 1, 2022, https://www.iflscience.com/company-plans-to-drill-20-kilometers-into-earth-to-tap-virtually-unlimited-energy-62788
Adele Peters, “These 12-mile-deep holes could convert power plants from fossil fuel to geothermal,” Fast Company, Feb, 8, 2022, https://www.fastcompany.com/90717968/these-12-mile-deep-holes-could-convert-power-plants-from-fossil-fuel-to-geothermal
Jona Jaupi, “Inside the mind-blowing plan to dig Earth’s deepest hole and ‘unleash limitless energy.’ The Sun, March 10, 2022, read in the New York Post, July 4, 2022, https://nypost.com/2022/03/10/inside-the-mind-blowing-plan-to-dig-earths-deepest-hole-and-unleash-limitless-energy/
Becky Ferreira, “Company Plans to Dig World's Deepest Hole to Unleash Boundless Energy,” Vice, March 9, 2022, https://www.vice.com/en/article/g5qknw/company-plans-to-dig-worlds-deepest-hole-to-unleash-boundless-energy
“Superhot Rock Geothermal,” Clean Air Task Force, Oct. 2021, https://www.catf.us/wp-content/uploads/2021/09/CATF_SuperhotRockGeothermal_Report.pdf
“Unlocking the true power of clean geothermal energy.” Quaise, accessed July 5, 2022. https://www.quaise.energy/#timeline
David Roberts, “Geothermal energy is poised for a big breakout.” Vox, Oct 21, 2020, https://www.vox.com/energy-and-environment/2020/10/21/21515461/renewable-energy-geothermal-egs-ags-supercritical
Zach Winn, “Tapping into the million-year energy source below our feet: MIT spinout Quaise Energy is working to create geothermal wells made from the deepest holes in the world.” MIT News, June 28, 2022, https://news.mit.edu/2022/quaise-energy-geothermal-0628
“New drilling technologies,” Wikipedia, last edit May 2, 2018, https://en.wikipedia.org/wiki/New_drilling_technologies
“Unlock Near-Limitless Deep Geothermal Energy,” YouTube, New SciTech, Mar 3, 2022. https://www.youtube.com/watch?v=fb9JWqB3c04
Skima Jos, “PLASMABIT DRILLING SYSTEM,” YouTube, Oct 21, 2019, https://www.youtube.com/watch?v=9QSbcC6JeIc
David Biello, "Fracking Could Help Geothermal Become a Power Player,” Scientific American, July 29, 2013, https://www.scientificamerican.com/article/fracking-for-renewable-power-geothermal/
Lots, lots more available on the internet.
Quaise: Portland (Oregon) General Electric shut down its coal-fired power plant at Boardman, Oregon last year. I’ve wanted to urge someone—Bill Gates/TerraPower?—to build a molten salt fission reactor there, to re-fire the plant. Maybe you could do it instead with a deep geothermal well? I wish I could tell you who to talk to at PGE, but my inquiry into the condition of the turbines/generators/etc. at Boardman went unanswered.
Is there an average depth of sedimentary layers? How long to rotary-drill through that? Then how long to go the rest of 12 miles through basement rock with the plasma drill? And what might the total cost of such a well be? And how much would a conventional rotary-drilled hole that deep cost? Except that you can’t go that deep with rotary drilling. Can you give me some way to compare costs?
How long to drill 7 miles through basalt, with rotary bits? How many drill head changes?
70 meters/hour? 5 cm bore? How big a bore would you need for a (pick a size—500 MW?) GT plant? How fast could you drill that with 1 MW? 2 MW? Could a gyrotron be designed to use 5 MW?
Does the production well have to be larger diameter than the injection well? How much?
How would you refire a gas plant running a gas turbine?
Technology developed by Paul Woskov, Senior Research Engineer at MIT’s Plasma Science and Fusion Research Center, being tested right now, will change all of that. Boston-based Quaise Energy, an MIT spin-off, will drill through softer, near-surface sedimentary rock with a conventional rotary drilling rig, then switch to a plasma guide that vaporizes its way through harder igneous “basement” rock with millimeter-wavelength electron beams generated in a device called a gyrotron. Gyrotrons are used to heat plasma for nuclear fusion experiments; they are well-understood, off-the-shelf technology.
Rotary drilling has gone as deep as 7 ½ miles. Russia’s Kola Superdeep Borehole went that deep, but took 20 years to drill (it was a science experiment, not a production well). Quaise thinks they can go 20 km/12 ½ miles deep in as little as 100 days. That deep, the rock is often as hot as 500 °C. Steam that hot should generate power with an efficiency in the low 40 percentile range—you'd need half as much power plant as at 350 °--and do it with the same "off the shelf" equipment and workers used in coal-fired power plants now, easing and speeding the transition to clean, inexhaustible energy awhile maintaining those jobs.
Quaise hopes to drill a 30-foot-deep test bore at Oak Ridge National Laboratory in 2022, a 330-foot deep well in New Mexico next, and, with AltaRock Energy, a 3,300 foot bore at the Newberry Volcano in Central Oregon, where AltaRock hopes to have a demonstration power plant running by 2026. They mean to begin “refiring” coal-fired power plants to geothermal energy in 2028.
Quaise is working with 1 MW gyrotrons because those are already available. They could drill faster with more power; they’re talking about 2 MW, so far, and I read some discussion of 10. You can do 2 MW with a very large diesel generator—or a very small nuclear reactor, which might be the ideal power supply for a rig designed to move from site to site and drill a bunch of wells. The energy beam melts the rock at up to 3,000 °C, “vitrifying” it to line the bore with glass. The excess vaporized/molten rock is blown out of the hole with argon, which is both non-reactive and transparent to millimeter-wavelength frequencies.
"Theoretical Considerations Thermodynamic calculations suggest a penetration rate of 70 meters / hour (230 feet / hour) is possible in 5 cm (1.97 inches) bores with a 1 MW gyrotron that couples to the rock with 100% efficiency. Use of lower or higher powered sources (e.g. 100 kW to 2 MW) would allow changes in bore size and/or penetration rate. "
"Figure 4 shows the relationship of Power, wellbore diameter and rate of penetration (ROP). From this relationship, a 5 cm (1.97 in) diameter wellbore could be penetrated via vaporization only at 50 m/hr (150 ft/ hr) with 1 MW of power. If we consider the Air Force’s 2 MW gyrotron, we could penetrate (with full vaporization) a 15 cm (6”) diameter wellbore at about 10 m/hr (30 ft/ hr) or a Figure 3. Wellbore diameter vs. power density DE-EE0005504 Final Report Impact Technologies LLC Massachusetts Institute of Technology 14 30 cm (12”) bore at 7 m/hr (21 ft/ hr) independent of rock hardness. That same rate could be obtained via only melting using a reduced estimated 700 kW of power. Further, for EGS sizes, a 15” bore could be drilled (with full vaporization) at 80 m/hr (262 ft/hr) with a 10MW gyrotron, or only 2.5 MW if only melted. These ROP estimates would be reduced by the actual MMW absorption efficiency, which is currently estimated at 70%. As noted, they could be increased by not requiring 100% vaporization of all rocks encountered- resulting in utilizing only ¼ to 1/3 of the vaporization energy listed." https://www.osti.gov/servlets/purl/1169951 .
Figure 4 wouldn't copy. But 2 MW gyrotron, 6" wellbore, 30 ft/hr through hard rock; 10 MW, 15" bore, 262 ft/hr. Wow.
Quaise thinks they can drill to supercritical-hot rock anywhere on the planet, including the grounds of any coal plant they wish to convert. They hope to produce energy for 1 to 3 cents per kWh, cheaper than coal—and you don’t have to buy your power plant a train load of coal every day. Apparently a ton of coal went from $36 in Oct. 2021, to $110 in late 2021 to $385 on July 5, 2022 (businessinsider.com/commodities/coal-price). At ~$385 per ton delivered, if a car carries 116 tons and each train is 115 cars (a large power plant is supposed to burn a train load every day) = $5,135,900 per train load of coal (up from less than $500 k a year ago!?). A train a day would be $1.875 billion a year just for fuel!?
I do wonder about something. Melting/vaporizing the rock, and letting some of it harden into glass lining the bore, sounds like a wonderful way to avoid having to lower steel casings 12 miles down a well shaft, and grout them in. But I wonder how durable it will be in practice? Any movement of the rock strata, as might be induced by fracking the rock, is going to tend to crack or break that glass. It is not going to be homogenous, like manufactured glass: it will be full of impurities and bubbles and stress lines and it sounds like something that will want to crack. Any pockets of water (or hydrocarbons?) will explode, at those temperatures. And changes in temperature, especially rapid changes, will also tend to fracture the glass; all of Paul Woskov's test bores into rock slabs in his laboratory broke, which tends to happen when you heat the middle of something, but not the edges, very hot, very fast. That might not matter, or fixing it might be as simple as adding something like Radiator Stop-Leak to the injection water. And even if these wells do turn out to need steel casings, being able to drill 12 miles deep in 100 days will change the world. But it will be interesting to see how well those vitrified casings hold up.
--- --- ---
Slovakia-based PLASMABITS is exploring similar technology, but so far is talking about drilling 10 km deep, not 20, where temperatures are ~350 °C, not 500, and accessing GE under 70 percent of Earth’s surface, not 90 percent. Supercritical heat is what will make geothermal as efficient and much less expensive than coal. PLASMABITS is also talking about using plasma drilling to explore for—and extract?—deep-rock minerals, and to reduce the time and cost of boring tunnels for subways, hyperloops. … Their logo is GA Drilling, where GA stands for Geothermal Anywhere.
There are more than 8,500 coal-fired power plants around the world, totaling over 2,000 gigawatts of capacity. Geothermal capacity, across 29 countries, is only 15.4 GW. If deep plasma drilling works and we get busy we might transfer that 2 k GW (2 TW, terawatts) from coal to clean geothermal in a decade. If we’re very lucky, that might actually be soon enough. See Post No. 1 on methane excursions.
It’s still far easier to get a permit to drill for oil/gas on public lands than it is a geothermal well.
------------
There is a discouraging, undated report by the U.S. DOE Office of Fossil Energy and Carbon Management [i] detailing their goal of making coal-fired power generation cleaner and more efficient (from 33 percent average at present into the low 40s) by 2040 or thereabouts. Some people just don’t get it. We need to stop burning coal, right now, or the future has no future. DOE would be much better advised to spend its taxpayer money on deep geothermal, or molten-salt nukes, or anything but coal. Is this what happens when government agencies get captured by the industries they are supposed to regulate?
https://www.energy.gov/fecm/science-innovation/office-clean-coal-and-carbon-management/advanced-energy-systems/transformative
Quaise had raised $63 million as of Feb. 2022.
"A supercritical power plant can be 4 to 10 times as efficient as subcritical. At 400 °C, ten times the energy as at 200 °C"!? That’s not what I see investigating nukes; twice the temperature means twice the pressure and only half again the power output. Still, "they" say that super-deep geothermal could produce power less expensively than on-shore wind. At 500 °C, off-the-shelf supercritical coal-plant equipment works fine. and the supply lines, repair parts and manufacturing capability is already there, as are a whole bunch of already-built power plants that only need their fuels switched.
“Temperatures at 20 km depth are above the supercritical point of water, which allows ten times more energy to be transferred given the same volumetric flow.[6]” Wikipedia, Quaise. ???? I don't think that's right. Wish it was ... .
---------
References
Jack Dunhill, “Company Plans To Drill 20 Kilometers Into Earth To Tap "Virtually Unlimited" Energy,” IFL Science, Mar 1, 2022, https://www.iflscience.com/company-plans-to-drill-20-kilometers-into-earth-to-tap-virtually-unlimited-energy-62788
Adele Peters, “These 12-mile-deep holes could convert power plants from fossil fuel to geothermal,” Fast Company, Feb, 8, 2022, https://www.fastcompany.com/90717968/these-12-mile-deep-holes-could-convert-power-plants-from-fossil-fuel-to-geothermal
Jona Jaupi, “Inside the mind-blowing plan to dig Earth’s deepest hole and ‘unleash limitless energy.’ The Sun, March 10, 2022, read in the New York Post, July 4, 2022, https://nypost.com/2022/03/10/inside-the-mind-blowing-plan-to-dig-earths-deepest-hole-and-unleash-limitless-energy/
Becky Ferreira, “Company Plans to Dig World's Deepest Hole to Unleash Boundless Energy,” Vice, March 9, 2022, https://www.vice.com/en/article/g5qknw/company-plans-to-dig-worlds-deepest-hole-to-unleash-boundless-energy
“Superhot Rock Geothermal,” Clean Air Task Force, Oct. 2021, https://www.catf.us/wp-content/uploads/2021/09/CATF_SuperhotRockGeothermal_Report.pdf
“Unlocking the true power of clean geothermal energy.” Quaise, accessed July 5, 2022. https://www.quaise.energy/#timeline
David Roberts, “Geothermal energy is poised for a big breakout.” Vox, Oct 21, 2020, https://www.vox.com/energy-and-environment/2020/10/21/21515461/renewable-energy-geothermal-egs-ags-supercritical
Zach Winn, “Tapping into the million-year energy source below our feet: MIT spinout Quaise Energy is working to create geothermal wells made from the deepest holes in the world.” MIT News, June 28, 2022, https://news.mit.edu/2022/quaise-energy-geothermal-0628
“New drilling technologies,” Wikipedia, last edit May 2, 2018, https://en.wikipedia.org/wiki/New_drilling_technologies
“Unlock Near-Limitless Deep Geothermal Energy,” YouTube, New SciTech, Mar 3, 2022. https://www.youtube.com/watch?v=fb9JWqB3c04
Skima Jos, “PLASMABIT DRILLING SYSTEM,” YouTube, Oct 21, 2019, https://www.youtube.com/watch?v=9QSbcC6JeIc
David Biello, "Fracking Could Help Geothermal Become a Power Player,” Scientific American, July 29, 2013, https://www.scientificamerican.com/article/fracking-for-renewable-power-geothermal/
Lots, lots more available on the internet.
Quaise: Portland (Oregon) General Electric shut down its coal-fired power plant at Boardman, Oregon last year. I’ve wanted to urge someone—Bill Gates/TerraPower?—to build a molten salt fission reactor there, to re-fire the plant. Maybe you could do it instead with a deep geothermal well? I wish I could tell you who to talk to at PGE, but my inquiry into the condition of the turbines/generators/etc. at Boardman went unanswered.
Is there an average depth of sedimentary layers? How long to rotary-drill through that? Then how long to go the rest of 12 miles through basement rock with the plasma drill? And what might the total cost of such a well be? And how much would a conventional rotary-drilled hole that deep cost? Except that you can’t go that deep with rotary drilling. Can you give me some way to compare costs?
How long to drill 7 miles through basalt, with rotary bits? How many drill head changes?
70 meters/hour? 5 cm bore? How big a bore would you need for a (pick a size—500 MW?) GT plant? How fast could you drill that with 1 MW? 2 MW? Could a gyrotron be designed to use 5 MW?
Does the production well have to be larger diameter than the injection well? How much?
How would you refire a gas plant running a gas turbine?
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