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Can a Geothermal Startup Vaporize Rock to Drill the Deepest Holes?
- nayuki 2y agoA relevant video by Real Engineering: "Geothermal Energy is Changing" https://www.youtube.com/watch?v=b_EoZzE7KJ0 https://www.youtube.com/watch?v=b_EoZzE7KJ0 (21m53s) [2025-03-01] The company being discussed is Quaise Energy: https://www.quaise.energy/ https://www.quaise.energy/ , https://en.wikipedia.org/wiki/Quaise https://en.wikipedia.org/wiki/Quaise
- stringl45 2y agoOne thing that video left me wondering is what happens to the vaporized rock; how are we collecting or transporting it so it doesen't immediately re-solidify, stringify and block the hole?
- cassepipe 2y agoIt's true that it's not entirely clear but it seems there's a nitrogen gas that pushes the gasses back up ? It's also not clear how much of the rock mass actually resolididy instead going away as gas but for the part that does, it seems to be do so in a fashion that resembles mineral wool.
- doodlebugging 2y agoThat's a valid question. As the vaporized rock cools it needs to be directed to the annular walls of the borehole being drilled. If it flutters chaotically up the along the drillstring and sticks itself to the drillstring then you are effectively blocking the borehole as you drill. Even if you rotate the drillstring the cumulative effect is that the drillstring becomes a long length of sandpaper or a vertical grinder, grinding the fused rock from the annulus above where you are currently drilling.
- mrguyorama 2y agoYou can see in that very video that it's not even an unsolved problem, it's an unaddressed problem. They currently handwave it away as "vent the molten rock" as if that is a solved problem. At 6:34 in the video, they very briefly show a running test drill, and then cut immediately to the ceiling of the test chamber with a large specimen of rock wool. That rock wool will completely clog any mechanism they could come up with. How do you reliably transport rock wool from 20 miles underground to the surface? This project/company is a dead end unless they could magic away that problem.
- cassepipe 2y agoIt is only shortly mentionned in the video but it seems like one of the main issues is what happens when water starts infiltrating your hole (it's unclear how much the glassified walls of the holes are a protection against that) and then you waste a lot of energy vaporizing liters and liters of water. Unless... you close the hole at the top to collect the steam and have it turn a turbine to recoup electricity expenditures ?
- LadyCailin 2y agoIf the hole is 2 miles long, I assume the steam would condense before reaching the top. And I guess lowering the pressure again, so I don’t know if that’s possible. But I’m not a physics expert.
- doodlebugging 2y agoAt depth, natural gas is in the liquid phase in the reservoir due to high temperatures and overburden pressure. Once the drillbit penetrates the seal of the formation containing natural gas or other liquids then the gas will begin to be carried up the annulus of the well in the drilling mud to the surface. As it moves closer to the surface it expands and crosses into the bubble point into the gas phase which is the dangerous condition that leads to blowouts and the loss of the well and potentially lives at the surface. It is important to be able to detect the formation boundaries and to have the mud weight tailored to the expected pressures within the target zones so that blowouts can be avoided. Pre-drill predictions of downhole pressures are made from seismic data and can be extremely accurate, especially when correlated with borehole data from regions with similar geologic history. I did pre-drill pressure predictions as a geophysicist. Very interesting stuff. Here is a little info about well control and gas kicks.[0] [0]https://www.drillingmanual.com/gas-kick-behavior-expansion-migration-well-control/ https://www.drillingmanual.com/gas-kick-behavior-expansion-m...
- Animats 2y agoWasn't Quaise on HN before, years ago? They've been talking this up since 2018. The competing technology is diamond drill bits.[1][2]. As synthetic diamonds have become cheaper, drill bits have improved. The old Hughes-style bits with what looked like big bevel gears now have a competitor. The key question is how much drilling you can do before you have to back out the whole drill string. That's a slow process, which gets slower as the drill string gets longer. Polycrystalline diamond bits now sometimes last for 3000+ meters. Maybe longer. Comments from anyone in the drilling industry? [1] https://okbit.com/choose-a-geothermal-drill-bit/ https://okbit.com/choose-a-geothermal-drill-bit/ [2] https://www.slb.com/products-and-services/scaling-new-energy-systems/geothermal/geothermal-well-construction/geothermal-drill-bits https://www.slb.com/products-and-services/scaling-new-energy...
- Retric 2y agoQuaise is also aiming for faster drilling not just longer lasting drills. Anyway, seems like the obvious solution is to stack multiple drill bits at the end and detach ones that get used up. Obviously this doesn’t work, but it’s not clear to me why it shouldn’t.
- CorrectHorseBat 2y agoWell, where are the used up drill bits supposed to go to in a hole just as wide as the bits itself except for up and out?
- Retric 2y agoAgain going for obvious solution, drop it, back up a few meters and drill around. Alternatively, have pre drilled side paths for drill bit drop off.
- cassepipe 2y agoHow do you pre-drill side paths ? Isn't being able to drill the hard part ? I am not saying it's dumb but from what I know about the industry (almost nothing) it does not seem simple at all
- ninetyninenine 2y agoI feel the energy spent vaporizing the rocks is more then the energy gained.
- littlestymaar 2y agoThey plan to use just a megawatt of power to drill, it's not even close.
- victorbjorklund 2y agoNo, if it works as planned then the energy is cheap in comparison to the total cost of drilling a hole.
- nonelog 2y agoActually, the real trick is to invent the technology that eliminates the need to drill so deep. But for that invention to be made/found, we need to go a bit more "quantum".
- cnote337 2y agoI'm a geologist. I work on well sites for a living. My biggest concerns about what have been talked about in the video are with regards to rock removal, and hole stability. But those are always my concerns. The oil and gas industry currently uses "mud" either oil based or water based, in order to keep their holes from collapsing on themselves. Holes collapse. It's what they want to do, this is a factor of overburden - the collective weight of the rock above the hole 'pushing' down. It is also the primary means of communication with downhole tools through mud pulse telemetry, and the primary means of removing rocks - currently in the form of cuttings. There is no mention of this mud system or other alternative (an innovation that would also need to be ground breaking for the industry) that will 1) keep the hole from collapsing 2) remove the volume of rock required to continue going down and 3) allow communication with your downhole tools. It feels like this is a massive hole in the logic.
- svantana 2y agoI think the idea is that the heat from the radiation turns the walls of the hole into a very hard glass structure, which should be hard enough to withstand the pressure.
- aurizon 2y agoat 10,000 feet in a thermal area the rock is very hot. Hot rock is ductile and holes will gradually close. Some deep hard rock mines in Northern Ontario encounter this problem where mine working gradually close under extreme pressure over time. The closure can be instant = rock-burst = a local micro-quake. Often there is lateral shear as well. The deepest gold mines in Witwatersrand in South Africa are over 160 degrees in places and workers wear vented/cooled suits. They also have refrigerated cold rooms they can jump into to get cool and get back to another work session.
- mcswell 2y agoThere's an old SciFi story here: https://www.gutenberg.org/cache/epub/30797/pg30797-images.html https://www.gutenberg.org/cache/epub/30797/pg30797-images.ht... that uses that idea as part of the plot. The hole is not very deep, maybe 150 feet, so the "glass" walls would presumably be strong enough. Much deeper, though, and the walls would almost certainly not be able to withstand the pressure. What I was wondering when reading the story, though, was what happened to all the rock that was vaporized. It has to leave the hole, else it will prevent the energy beam (in the case of the story, a laser beam) from getting to the bottom of the hole. If you've ever seen smoke (or even steam) coming out of a smoke stack, you have to wonder how the efficiency of the beam would not be cut to zero after the first few feet.
- worldvoyageur 2y agoEavor is a Canadian geothermal company that does closed loop systems with diamond drills and insulated drill pipe. https://www.eavor.com/technology/ https://www.eavor.com/technology/ Closed loop and insulated pipe allows a geothermal project to be drilled into hot rock, which is pretty much everywhere, even if there is no water. They have a demonstration project in Alberta, a 'commercial' project in Geretsried, Germany (4500 meters, 64MW thermal, 8.2MW electric) and a deep demonstration project in New Mexico (5500 meters, no news since early 2023). From the company website, it looks like the projects work though Eavor doesn't give any data on their projects that would help calculate the economics. The heavy presence of government in their media suggests that, at least for now, significant government involvement is required to get projects built.
- thinkcontext 2y agoHype for this is extremely premature, they've only drilled inches in a lab.
- giarc 2y agoFounder was on What's Your Problem podcast recently [1] and I seem to recall them having much deeper wells already complete. https://www.pushkin.fm/podcasts/whats-your-problem/harnessing-the-heat-deep-beneath-our-feet https://www.pushkin.fm/podcasts/whats-your-problem/harnessin...
- thinkcontext 2y agoThis article from 2 days ago says they have a test rig that is drilling outside. They don't say exactly how deep they have drilled but mentions they have another site where they will attempt to drill up to 100 feet. So sounds like they are at the very beginning of piloting. I'm not going to listen to an hour podcast to see if it is claiming anything different, if you have a text source I'd be interested. https://www.canarymedia.com/articles/geothermal/the-smell-of-toasted-rock-could-spell-victory-for-geothermal-energy https://www.canarymedia.com/articles/geothermal/the-smell-of...
- istjohn 2y agoI transcribed the podcast for you, but I think you're right. https://pastebin.com/raw/PG5JdAKv https://pastebin.com/raw/PG5JdAKv
- lightedman 2y agoWhy not just use a laser? I vaporize rock instantly with an 80w CO2. vacuum the dust up and blow it out the other end, done. Throw it on a galvo, you can control where it aims and fires.
- HPsquared 2y agoI don't know much about lasers, but this seems a very "dirty" environment for that sort of thing. Wouldn't the lenses etc get all fouled up?
- mcswell 2y agoDust? Vaporized rock going through a vacuum is not going to be kind to the inside of that vacuum.
- lightedman 2y agoYes, this is a known thing to anyone that does stone engraving for a hobby. Those are then considered consumable parts in the operation.
- avsteele 2y agoyour beam waist is going to increase (and intensity is going to drop) after a few hundred meters. you'd have to lower the whole laser down the hole
- bilsbie 2y agoMaybe use adjustable lenses?
- lightedman 2y agoThat's what adjustable diopters are for. Also, at certain power levels, the beam is self-focusing.
- notorandit 2y agoSome maths. 1 squared meter surface times 10 km in depth yields ... 10,000 cubic m of mass to be vaporized and then "dispersed" into the atmosphere. At a density of 5.5 kg/dm^3 it would weight about ... 55 thousands metric tonnes of rock. To vaporize 1 kg of liquid water it takes 2250 kcal of energy. If that mass was water it would require 1.23e11 kcal of energy. I suspect that both the amount of energy needed and the amount of pollution added would be unbearable. And this is for a hole that's "just" 10 km deep.
- foobarian 2y ago1 m^2 x 10,000 m = 10,000 m^3 10 km^3 = 10 x 1,000 x 1,000 x 1,000 m^3 != 10,000 m^3
- notorandit 2y agoCorrect! I fixed my numbers too. Still a lot of stuff.
- istjohn 2y agoYour cross section area is off by two orders of magnitude. They currently are drilling a 0.008 m² hole at one meter per hour with 1 MW of power. They hope to scale that up to a 0.032 m² hole while maintaining the same rate of depth penetration and energy use per meter [0]. 0. https://m.youtube.com/watch?v=b_EoZzE7KJ0&t=500s https://m.youtube.com/watch?v=b_EoZzE7KJ0&t=500s
- itishappy 2y agoThink you're somewhat off. Quaise says they intend to allow their tech to be "plugged into existing oil rigs," and most boreholes are 5-20 in wide. 20 in down 7.6 mi is 0.2 m^2 down 12321 m. This gives 2500 m^3 or 2.5e-6 km^3 of rock. Google says "rocks are generally between 1600 kg/m^3 (sediments) and 3500 kg/m^3 (gabbro)" so going with 2500 km/m^3 that would be 6240000 kg, 6.24 Gg, or 6.24 thousand metric tons. Heat of vaporization of water is roughly 2250 kJ/kg, or 537 kcal/kg, so if the mass was water it would need 14e9 kJ, 14 TJ, or 3.35e9 kcal to vaporize. For a 5 in borehole divide all the above by 16. This ignores the heat required to actually change the temperature of the water, but I'm betting you can get a lot of that back via condensation, and for this reason I'd also assume that much of the rock will not end up in atmosphere. These assumptions also go entirely out the window of there's an inflow of material, but unfortunately I'm betting that's exactly what will happen. Edit: Fixed post after I confused radius and diameter. Someone should probably check my math as well.
- api 2y agoI have always thought that very deep geothermal is a massive potential source of renewable energy that gets far too little attention. If we can make it work, we have a source of "limitless" (at terrestrial human scale) energy that doesn't require expensive battery backup and is dispatchable. It could also be used as a source of industrial process heat, cogeneration (if it's safe to do near or inside city limits), etc. I've even seen proposals to make methane or liquid fuels by injecting CO2 and H2 or H2O down there and using it as a thermally driven in situ synfuel reactor. Solar is one way of using a ready-made natural nuclear reactor. This is another. Some geologists believe the Earth's core is a natural fission reactor, and a few people have proposed other even more exotic possibilities: https://www.nature.com/articles/srep37740 https://www.nature.com/articles/srep37740
- WalterBright 2y agoI read about this years ago on HN and then ... nothing. Glad to see it back in the news. It really would be tremendous if it works.
- actionfromafar 2y agoDon’t tell the Evangelicals, they will believe you are drilling a hole to hell. (And the oil companies will view the competition as from Satan?)
- CokeFaultSoyuz 2y ago[dead]
- foobarian 2y ago<armchair geologist hat on> Wonder if they could drill a stable hole with a honeycomb arrangement of lasers like engines on the Starship, but with smaller radius. It wouldn't strictly be an empty hole but just a bundle of small diameter holes. Whatever the laser hits, vaporizes until it's out or turns into glass on the side. Whatever caves in just keeps getting vaporized.
- dhosek 2y ago63 comments and no one brings up Betteridge’s Law of Headlines: "Any headline that ends in a question mark can be answered by the word no." (The 63 comments essentially support Betteridge.)