14 ms·

Fusion tech finds geothermal energy application

153 points by Lisdexamfeta 2y ago

eluketronic 2y ago
This is pretty interesting but it seems like there’s a massive component of this system that is yet to be proven viable—from the article: “Drilling a hole is challenging enough,” says Tester. “But actually running the reservoir and getting the energy out of the ground safely may be something very, very far off in the future.” Is there any existing +3km deep geothermal well energy system in use?
- dylan604 2y ago
  And what do you make the pipes out of that do not get destroyed from living at those depths?
  - deleted 2y ago
    [deleted]
  - TheDudeMan 2y ago
    Steel
- Lisdexamfeta 2y ago
  Utah FORGE is the deepest I'm aware of: https://utahforge.com/project-research https://utahforge.com/project-research. Well 58-32 goes to 2.2km. 78B-32 goes to 2.9km. 16B(78)-32 appears to break 3km. But FORGE is mostly based around research, from what I understand, rather than rolling out broad-based commercial geothermal.
- auspiv 2y ago
  Fervo Energy is making great progress in this area. They've drilled a injector/producer pair, frac'd between them (exactly like oil/gas), and pump water at ~60 L/s. Whatever goes into the injector comes out the producer a few hours later much hotter. Their proof of concept produces 3 MW, and uses ~1MW to power the injection pumps. They are doing a full scale plant in Utah now, and expect ~8 MW net for each injector/producer pair. https://eartharxiv.org/repository/view/5704/ https://eartharxiv.org/repository/view/5704/ https://fervoenergy.com/fervo-energy-breaks-ground-on-the-worlds-largest-next-gen-geothermal-project/ https://fervoenergy.com/fervo-energy-breaks-ground-on-the-wo...
- jeffbee 2y ago
  3km would be far below average for new oil and gas wells in America. Climate change sucks but the technology for punching holes in the ground with extreme aspect ratios is really cool. A reason I am more interested in geothermal than nuclear for "base load" generation is because geothermal can reuse our existing drilling technology and workforce.
  - audunw 2y ago
    Yeah, and think about the amount of political support you could get for geothermal projects if workers from the oil and gas sector could see a clear and easy path to adapt their skills. Globally viable geothermal power generation would be an absolute game changer for fighting climate change. It doesn’t have to be better than nuclear. If it’s even close to being as good, the benefits of getting ex oil/gas people/companies on board would more than outweigh the difference. The growth rate could potentially hit levels that make a substantial impact on climate change within a decade of the initial ramp.
    - zer00eyz 2y ago
      Geo would make a good transition project for the drilling side of the business. It's counter intuitive but if we did move that way we need a LOT more petro infrastructure going forward. And without irony it would be better for us. Capturing all the wasted natural gas (that gets flared off) as a reorient to maintain existing wells lowers carbon foot print and makes the use of gas less attractive due to cost. Petrochemical products aren't going away any time soon. Unless we want to go back to hunting whales for things like lubricants. Having useful plastics (because there are tons of medical uses). And we're not getting rid of fertilizer (cause feeding 8 billion people is hard). There are reasons to keep the drilling side and the current matinence side around doing what they do today while lowering carbon foot print.
      - pfdietz 2y ago
        > Petrochemical products aren't going away any time soon. Unless we want to go back to hunting whales for things like lubricants. Synthetic lubricants (like Mobil-1) are a thing.
auspiv 2y ago
"The deepest man-made hole, which extends 12,262 meters below the surface of Siberia, took nearly 20 years to drill. As the shaft went deeper, progress declined to less than a meter per hour—a rate that finally decreased to zero as the work was abandoned in 1992. That attempt and similar projects have made it clear that conventional drills are no match for the high temperatures and pressures deep in the Earth’s crust." This is true. Neither the article nor the CEO of the microwave drill company say why. At that depth, rock isn't a solid. It behaves plastically. The traditional tri-cone bit used could make progress, but it kind of just started "massaging" the rock. The bit (as all bits do) wore out. They pulled the drill string out of the hole to put a new bit on. The borehole would close back in during the multiple days it took to pull 40kft of drill string out, change the bit, and put it back in. Progress was not possible. Unless the microwave drill includes some enormous cooling system (that works 40kft down hole even when the drillstring is removed!), they will face the same issues. Also, separately, I saw pictures of the resulting lab-drilled hole on LinkedIn the other day. The hole shows a high rugosity (qualitative description of the roughness of a borehole wall). Similar photo here - https://spectrum.ieee.org/media-library/image-of-a-rock-surface-with-a-melted-hole-in-the-middle-that-appears-to-extend-deep-into-the-rock-surface.jpg https://spectrum.ieee.org/media-library/image-of-a-rock-surf.... That's a ugly hole, and would be very difficult to run casing into it. Further - traditional well drillers' #1 focus is controlling pressure downhole (typically done by varying the density of the drilling mud). If the pressure becomes too great, a blowout can happen, which is bad news for everyone involved (see the BP Deepwater Horizon incident). For geothermal wells, they presumably will try to avoid hydrocarbons. However, rock far above water boiling point can cause a BLEVE (boiling liquid expanding vapor explosion), which is also undesirable. Super curious to see how they intend to control bottomhole pressure with statements like this - "Instead of pumping fluid and turning a drill, we’ll be burning and vaporizing rock and extracting gas, which is much easier to pump than mud."
- Terr_ 2y ago
  > At that depth, rock isn't a solid. It behaves plastically. Sometimes this false-intuition comes out in sci-fi settings, when some terrible force scars a planet or moon with a big gash/puncture/fragmentation which appears semi-permanent, rather than being (relatively) quickly erased as the thing--a liquid on that scale--reflows back into a spheroid.
krunck 2y ago
If this microwave drill is vaporizing rock, how do they keep the vapor from re-condensing on the drill, wave guide, and shaft walls and eventually closing up the spaces between them causing things to get stuck?>
- Terr_ 2y ago
  Did some (metaphorical) digging, and it sounds like they expect most of the rock to condense as small particles inside a purge-gas, before it has a chance to adhere somewhere else. I imagine walls are an easier problem--just advance fast-enough compared to the deposition rate, and the thickening is controlled. Not sure about gradual buildup on the wave-guide, but some periodic cleaning mechanism (further back, away from rock-condensation) might be possible. ____________ > Even though the rocks are being vaporized, it does not mean that there is no material to be taken care of. “The gas will quickly recondense back to a very fine ash, which will then be taken up to surface by a purge gas. In our case, we will use nitrogen”, Matt [Houde] explains. https://geoexpro.com/an-order-of-magnitude-more-energy-for-drilling-twice-as-deep/ https://geoexpro.com/an-order-of-magnitude-more-energy-for-d... > MIT’s Paul Woskov, whose research is the bedrock of Quaise’s approach, spent a decade proving out the physics involved. The system will use a beam of millimeter-wave energy—an electromagnetic frequency in the territory of microwaves—generated by a gyrotron on the surface. The microwave beam shoots down the drill hole alongside a gas—nitrogen, air, or argon—and evaporates layers of rock deep in the Earth. Then the gas binds and carries the vaporized rock back up to the surface like a plume of volcanic ash. https://singularityhub.com/2022/02/14/startup-aims-to-drill-12-miles-into-earths-crust-to-tap-the-boundless-energy-below/ https://singularityhub.com/2022/02/14/startup-aims-to-drill-...
  - baking 2y ago
    There is a stand-off between the end of the waveguide and the bottom of the hole which prevents damage to the waveguide. It also causes the beam to spread out so the hole is made wider than the waveguide.
- TheDudeMan 2y ago
  Likely condenses into dust in midair and gets blown out.
api 2y ago
I’ve thought for quite some time that deep well geothermal could be a sleeping giant in energy. The Earth itself is a giant fission reactor and molten metal thermal battery, but for some reason nobody thinks about it. This would be far easier than fusion or even next generation full cycle fission but it’s barely funded.
- kaliszad 2y ago
  There are so many energy projects that need probably orders of magnitude less investment than even the geothermal You propose, e.g. like the sodium fuel cell I have been writing about from time to time. For instance sodium can be used in its metal form directly to produce electricity in a fuel cell e.g. as described in US3730776A (https://patents.google.com/patent/US3730776A/en https://patents.google.com/patent/US3730776A/en). The fuel cell does not require any special materials, however it still is a challenge to construct from the engineering point of view. Also, the proposed design can be greatly improved with additional knowledge about the reactions occurring. The resulting sodium hydroxide solution can be recycled using the well known Castner process, the "waste" hydrogen resulting from both reactions can be used as fuel or for other industrial processes. Btw. the energy density of sodium metal is 3694 Wh/kg and 3555 Wh/litre - so an order of magnitude more than a typical Li-Ion battery. Also, the advantage of decoupling capacity from power is dramatic. Of course, you can also split the process of storing and releasing of energy which can be an advantage. Last but not least, sodium in its metal form is not hard to store or to transport. At ~100°C it becomes liquid and therefore even easier to transfer using regular steel pipes.
  - api 2y ago
    I think you meant more investment but yes. That sodium battery sounds great for grid scale storage and maybe aviation. The major problem with lithium there is weight per kWh. Wouldn’t use it in anything consumer because liquid sodium loves to party.
    - kaliszad 2y ago
      No, I really meant less investment - you don't have to push seamless pipes 10+ km underground for the sodium fuel cell to work. It can literally be built in a garage. Liquid sodium is totally fine unless you pour water over it. You have problems with other substances too and it depends what use case and limits you have whether you are willing to go with sodium. For example, filling a big tank with normal gasoline is dangerous without protective atmosphere and other precautions like good grounding because it tends to produce flammable vapors that catch fire easily. Not a problem with sodium. Also, if you happen to spill sodium into water, it neutralizes quickly doing damage only for a short period of time. That cannot be said about any kind of mineral oil, gasoline that has a tendency to destroy ecosystems etc. Last but not least, you can produce sodium metal without begging mostly totalitarian/ authoritarian regimes for natural resources which is the case with the majority of fossil fuels today. Because of electronics and fine machines we learned a lot about how to make stuff water tight. Sodium is in my opinion mostly much easier to handle than hydrogen, which leaks even through steel, which you have to keep under high pressure to have any kind of decent volumetric energy density or cool to very low temperatures if liquid. If you used sodium for grid scale storage than you would more or less solve the electricity storage problem and most likely quite cheaply. The great thing about it is, you can store and transport sodium metal easily. Storing power for the winter becomes practical. For stationary stuff in homes or businesses you could probably use sodium too. You could replace old central furnaces with it and instead use the fuel cell and a heat pump perhaps with a small battery and PV to smooth out the peaks. That way you probably wouldn't need to upgrade the last mile of the grid in many places. You could power boats with it. For aviation it doesn't seem that great as you would still have to handle the resulting sodium hydroxide.
sfink 2y ago
Dumb question: is there any use for this for horizontal drilling? I'm imagining scaling up the size of the drill head to the size of a car-carrying bore hole, vaporizing the rock (or whatever gets in your way) and using some of it to recondense into tunnel liner, and blowing out the rest of the ash either back out the whole tunnel or via vertical(ish) vent tubes drilled periodically from the tunnel roof up. Though maybe the tunnel liner part is too much of a stretch. It sounds like the vaporized rock wants to turn to ash. I don't know if there's a way of concentrating the once-solid parts and keeping it hot enough while routing it to the tunnel wall. It just seems like a cool set of problems to solve, resulting in a self-contained (minus the energy source) burrowing drill that can create arbitrarily long stone tunnels underneath (non-volcanic) land. DIY lava tubes!
- deleted 2y ago
  [deleted]
- dylan604 2y ago
  The oil&gas industry makes heavy use of horizontal drilling already. Say you own land with a nice pocket of $$$ buried beneath, but you refuse them to put a well on your property. That's when they turn to horizontal drilling. Infamously stated as "if you have a milkshake and I have a milkshake, but I have a straw that reaches your milkshake, then I have all the milkshake".
  - bluGill 2y ago
    Modern laws are generally onto this, and if caught (a big if) bad things happen. This is also why oil and gas companies buy mineral rights anywhere they might be interested in - it lets them take your oil without worrying about it. Of course not everyone lives where law is caught up to this, but it is a big deal and so most places where it matters the courts know what is up.
    - njarboe 2y ago
      More like if they buy your mineral rights they now own your oil and have the right to extract it.
greenthrow 2y ago
Inaccurate title. "Finds" implies it is being or has been used. More accurate would be "Fusion tech proposed to be used in geothermal energy drilling."
gzu 2y ago
It's like if only we put more resources towards potential societal altering technologies like these instead of [insert random SAAS app]. Maybe tech investors aren't very comfortable with projects outside their domain knowledge and expect an quick return. Quaise last financing round was something like $20M...
- baq 2y ago
  one (1) good thing that may come out of OpenAI is thirst for electricity only satiable by fusion, just as demand for heat in UK could only be met by digging deeper for coal which ultimately spurred the industrial revolution.
  - m463 2y ago
    and coal mining (kind of) saved the forests and and drilling for oil (kind of) saved the whales.
    - rbanffy 2y ago
      Completely unintended side effect, but coal and oil might have created the need for massive rewilding efforts that might, ultimately not only save the forests, but winding cover back to pre-industrial levels.
  - dylan604 2y ago
    what a sad statement on the human condition that all of the other needs for limitless clean power did not meet the needs to justify developing fusion, yet you think that AI will? Jesus wept.
    - tivert 2y ago
      > what a sad statement on the human condition that all of the other needs for limitless clean power did not meet the needs to justify developing fusion, yet you think that AI will? Jesus wept. Well, AI has the promise to provide a supply of loyal slaves to anyone who can afford to pay for the electricity and compute. It's a capitalist's dream: with AI, they may never be forced by necessity to share a single thing with us poors again.
pfdietz 2y ago
Getting deep to hot rocks is important, but reducing the thermal resistance around the borehole is also important. Some schemes fracture the rock between two boreholes, but this requires fiddly positioning of the wells as well as the fractures. Another interesting approach is to increase the thermal conductivity of the rock around a single well. Much of the thermal resistance is in the rock close to the well (as can be seen by examining the relevant integral), so this doesn't have to affect too far out to have a significant effect. A company XGS Energy recently raised $20 M in series "A" funding for this. Their fluid (which is forced into fractures around the borehole) is proprietary, but is thought to contain graphite dust. Graphite can be three orders of magnitude more thermally conductive than rock, so incorporating it into even narrow fractures can have a major effect. https://news.ycombinator.com/item?id=40434975 https://news.ycombinator.com/item?id=40434975 https://jpt.spe.org/hot-rock-slurry-developer-of-emerging-geothermal-tech-readies-for-field-tests https://jpt.spe.org/hot-rock-slurry-developer-of-emerging-ge... (the field tests mentioned there must have been successful, as they raised that $20 M subsequently.) Because this technology involves a single well that remains sealed from the surrounding formation, it could be used in existing played-out oil or gas wells, some of which go quite deep (although that's in basins with low geothermal gradients or else the fossil fuels would have been destroyed.)
- baking 2y ago
  The $20M is for the field test which starts in July in California. https://techcrunch.com/2024/05/21/special-mud-helps-xgs-energy-get-more-power-out-of-geothermal-wells/ https://techcrunch.com/2024/05/21/special-mud-helps-xgs-ener...
  - pfdietz 2y ago
    Useful, thanks.
drtgh 2y ago
Has anyone calculated how much energy could be extracted before the cooling of the earth's crust, due such geothermal extraction, would turn irreversible the reservoir and unleash worse consequences than those "greenhouse gasses" mentioned? From how such progressive temperature change (extraction) would affect the dynamics of the Earth's core, among other things, to how it would affect such temperature to the nature chemical processes on the surface, how it would affect vegetal life (cultives), and so on. The planet is big, but we are talking about, lets say, a century of use or more. Has anyone calculated were would be the limit of holes (on geothermal a new hole each XX years due area cold down) before the "we never guessed that X could happen"?
- JoeAltmaier 2y ago
  Pretty sure the numbers are not comparable, not by many zeroes. Like, trillions of times more energy in the Earth's heat than humans could extract in a billion years. Add to that, Earth is heated by deep radioactive elements. A fission furnace. Not gonna burn out for a billion years, maybe not ever.
- lukan 2y ago
  - new heat is generated constantly in the earth by radioactive decay - how much is debated, but this alone probably dwarfs humans energy needs (the core of the earth is really, really BIG) The real danger is in creating local earth quakes, because that already happened.
  - pfdietz 2y ago
    Actually, it's estimated radioactive decay in the Earth is about 20 TW, which is also about equal to the current global rate of primary energy consumption. Geothermal can be better described as heat mining than it would be exploiting a steady state heat flow.
  - xeonmc 2y ago
    So essentially : - fusion - power of the Sun - fission - power of the Earth
deleted 2y ago
[deleted]
goda90 2y ago
> which itself yields no greenhouse gasses Does anyone know how much of the atmosphere's heat comes from geothermal energy as opposed to solar radiation? By extracting geothermal energy we'd be increasing that effect in the short term, but would it even be significant?
- lainga 2y ago
  0.087 W/m^2. Compare to 340 W/m^2 insolation. [] https://en.wikipedia.org/wiki/Earth%27s_energy_budget#Earth's_internal_heat_sources_and_other_minor_effects https://en.wikipedia.org/wiki/Earth%27s_energy_budget#Earth'...
  - kokanee 2y ago
    Interesting stuff, particularly the estimation that 140 TW of solar radiation are captured by photosynthesis. In arguments about the efficacy of tree-planting as a climate control effort, I've heard about the effect on albedo radiation and of course on the sinking of CO2, but I've never heard it pointed out that photosynthesis itself captures solar radiation that would otherwise be reflected heat.
peter_d_sherman 2y ago
I have often thought that in the future, there'd be a machine that you could scoop raw earth into (like "Mr. Fusion" in the movie "Back To The Future II") -- any kind of raw earth -- and the machine would automatically separate the raw earth into its constituent elements... Now, such a device would probably seem a little bit far fetched... But the first step in making such a device, if it could ever be engineered, would be to melt the inserted raw earth into a hot liquid state. (From this hot liquid state further chemical refinement processes could be completed, such as scooping out heavier elements from the bottom and lighter elements from the top of the liquid. Any emitted gasses could be captured and cooled down, liquified, etc. From there further chemical refinement processes of the liquids could take place, ultimately resulting in refined Elements being output...) This technology -- the ability to "melt rocks" (aka, the ability to melt raw earth, any raw earth notwithstanding its chemical composition) might just enable the taking of that first step to creating such a machine... Such a machine, should it ever exist, would find great application on Mars in the future, should it ever be able to get there... Anyway, I wish this company a lot of luck in their endeavors!
toss1 2y ago
This seems to have tremendous potential, and not just for geothermal! However, one issue with geothermal that I didn't see addressed is that iirc, geothermal systems start out great, but as water/fluid is pumped down and back up hot, minerals rapidly deposit themselves on the plumbing and decrease the system efficiency and ultimately kill it. Could this system be used to more quickly, cheaply, and regularly perform maintenance, or is this just one good step to get broad geothermal applications, and that remains a problem to be solved? It's be great to hear from any experts in the field - thx!

153 points by Lisdexamfeta 2y ago

This is pretty interesting but it seems like there’s a massive component of this system that is yet to be proven viable—from the article: “Drilling a hole is challenging enough,” says Tester. “But actually running the reservoir and getting the energy out of the ground safely may be something very, very far off in the future.” Is there any existing +3km deep geothermal well energy system in use?

dylan604 2y ago
And what do you make the pipes out of that do not get destroyed from living at those depths?
- deleted 2y ago
  [deleted]
- TheDudeMan 2y ago
  Steel
Lisdexamfeta 2y ago
Utah FORGE is the deepest I'm aware of: https://utahforge.com/project-research https://utahforge.com/project-research. Well 58-32 goes to 2.2km. 78B-32 goes to 2.9km. 16B(78)-32 appears to break 3km. But FORGE is mostly based around research, from what I understand, rather than rolling out broad-based commercial geothermal.
auspiv 2y ago
Fervo Energy is making great progress in this area. They've drilled a injector/producer pair, frac'd between them (exactly like oil/gas), and pump water at ~60 L/s. Whatever goes into the injector comes out the producer a few hours later much hotter. Their proof of concept produces 3 MW, and uses ~1MW to power the injection pumps. They are doing a full scale plant in Utah now, and expect ~8 MW net for each injector/producer pair. https://eartharxiv.org/repository/view/5704/ https://eartharxiv.org/repository/view/5704/ https://fervoenergy.com/fervo-energy-breaks-ground-on-the-worlds-largest-next-gen-geothermal-project/ https://fervoenergy.com/fervo-energy-breaks-ground-on-the-wo...
jeffbee 2y ago
3km would be far below average for new oil and gas wells in America. Climate change sucks but the technology for punching holes in the ground with extreme aspect ratios is really cool. A reason I am more interested in geothermal than nuclear for "base load" generation is because geothermal can reuse our existing drilling technology and workforce.
- audunw 2y ago
  Yeah, and think about the amount of political support you could get for geothermal projects if workers from the oil and gas sector could see a clear and easy path to adapt their skills. Globally viable geothermal power generation would be an absolute game changer for fighting climate change. It doesn’t have to be better than nuclear. If it’s even close to being as good, the benefits of getting ex oil/gas people/companies on board would more than outweigh the difference. The growth rate could potentially hit levels that make a substantial impact on climate change within a decade of the initial ramp.
  - zer00eyz 2y ago
    Geo would make a good transition project for the drilling side of the business. It's counter intuitive but if we did move that way we need a LOT more petro infrastructure going forward. And without irony it would be better for us. Capturing all the wasted natural gas (that gets flared off) as a reorient to maintain existing wells lowers carbon foot print and makes the use of gas less attractive due to cost. Petrochemical products aren't going away any time soon. Unless we want to go back to hunting whales for things like lubricants. Having useful plastics (because there are tons of medical uses). And we're not getting rid of fertilizer (cause feeding 8 billion people is hard). There are reasons to keep the drilling side and the current matinence side around doing what they do today while lowering carbon foot print.
    - pfdietz 2y ago
      > Petrochemical products aren't going away any time soon. Unless we want to go back to hunting whales for things like lubricants. Synthetic lubricants (like Mobil-1) are a thing.

auspiv 2y ago

"The deepest man-made hole, which extends 12,262 meters below the surface of Siberia, took nearly 20 years to drill. As the shaft went deeper, progress declined to less than a meter per hour—a rate that finally decreased to zero as the work was abandoned in 1992. That attempt and similar projects have made it clear that conventional drills are no match for the high temperatures and pressures deep in the Earth’s crust." This is true. Neither the article nor the CEO of the microwave drill company say why. At that depth, rock isn't a solid. It behaves plastically. The traditional tri-cone bit used could make progress, but it kind of just started "massaging" the rock. The bit (as all bits do) wore out. They pulled the drill string out of the hole to put a new bit on. The borehole would close back in during the multiple days it took to pull 40kft of drill string out, change the bit, and put it back in. Progress was not possible. Unless the microwave drill includes some enormous cooling system (that works 40kft down hole even when the drillstring is removed!), they will face the same issues. Also, separately, I saw pictures of the resulting lab-drilled hole on LinkedIn the other day. The hole shows a high rugosity (qualitative description of the roughness of a borehole wall). Similar photo here - https://spectrum.ieee.org/media-library/image-of-a-rock-surface-with-a-melted-hole-in-the-middle-that-appears-to-extend-deep-into-the-rock-surface.jpg https://spectrum.ieee.org/media-library/image-of-a-rock-surf.... That's a ugly hole, and would be very difficult to run casing into it. Further - traditional well drillers' #1 focus is controlling pressure downhole (typically done by varying the density of the drilling mud). If the pressure becomes too great, a blowout can happen, which is bad news for everyone involved (see the BP Deepwater Horizon incident). For geothermal wells, they presumably will try to avoid hydrocarbons. However, rock far above water boiling point can cause a BLEVE (boiling liquid expanding vapor explosion), which is also undesirable. Super curious to see how they intend to control bottomhole pressure with statements like this - "Instead of pumping fluid and turning a drill, we’ll be burning and vaporizing rock and extracting gas, which is much easier to pump than mud."

Terr_ 2y ago
> At that depth, rock isn't a solid. It behaves plastically. Sometimes this false-intuition comes out in sci-fi settings, when some terrible force scars a planet or moon with a big gash/puncture/fragmentation which appears semi-permanent, rather than being (relatively) quickly erased as the thing--a liquid on that scale--reflows back into a spheroid.

krunck 2y ago

If this microwave drill is vaporizing rock, how do they keep the vapor from re-condensing on the drill, wave guide, and shaft walls and eventually closing up the spaces between them causing things to get stuck?>

Terr_ 2y ago
Did some (metaphorical) digging, and it sounds like they expect most of the rock to condense as small particles inside a purge-gas, before it has a chance to adhere somewhere else. I imagine walls are an easier problem--just advance fast-enough compared to the deposition rate, and the thickening is controlled. Not sure about gradual buildup on the wave-guide, but some periodic cleaning mechanism (further back, away from rock-condensation) might be possible. ____________ > Even though the rocks are being vaporized, it does not mean that there is no material to be taken care of. “The gas will quickly recondense back to a very fine ash, which will then be taken up to surface by a purge gas. In our case, we will use nitrogen”, Matt [Houde] explains. https://geoexpro.com/an-order-of-magnitude-more-energy-for-drilling-twice-as-deep/ https://geoexpro.com/an-order-of-magnitude-more-energy-for-d... > MIT’s Paul Woskov, whose research is the bedrock of Quaise’s approach, spent a decade proving out the physics involved. The system will use a beam of millimeter-wave energy—an electromagnetic frequency in the territory of microwaves—generated by a gyrotron on the surface. The microwave beam shoots down the drill hole alongside a gas—nitrogen, air, or argon—and evaporates layers of rock deep in the Earth. Then the gas binds and carries the vaporized rock back up to the surface like a plume of volcanic ash. https://singularityhub.com/2022/02/14/startup-aims-to-drill-12-miles-into-earths-crust-to-tap-the-boundless-energy-below/ https://singularityhub.com/2022/02/14/startup-aims-to-drill-...
- baking 2y ago
  There is a stand-off between the end of the waveguide and the bottom of the hole which prevents damage to the waveguide. It also causes the beam to spread out so the hole is made wider than the waveguide.
TheDudeMan 2y ago
Likely condenses into dust in midair and gets blown out.

api 2y ago

I’ve thought for quite some time that deep well geothermal could be a sleeping giant in energy. The Earth itself is a giant fission reactor and molten metal thermal battery, but for some reason nobody thinks about it. This would be far easier than fusion or even next generation full cycle fission but it’s barely funded.

kaliszad 2y ago
There are so many energy projects that need probably orders of magnitude less investment than even the geothermal You propose, e.g. like the sodium fuel cell I have been writing about from time to time. For instance sodium can be used in its metal form directly to produce electricity in a fuel cell e.g. as described in US3730776A (https://patents.google.com/patent/US3730776A/en https://patents.google.com/patent/US3730776A/en). The fuel cell does not require any special materials, however it still is a challenge to construct from the engineering point of view. Also, the proposed design can be greatly improved with additional knowledge about the reactions occurring. The resulting sodium hydroxide solution can be recycled using the well known Castner process, the "waste" hydrogen resulting from both reactions can be used as fuel or for other industrial processes. Btw. the energy density of sodium metal is 3694 Wh/kg and 3555 Wh/litre - so an order of magnitude more than a typical Li-Ion battery. Also, the advantage of decoupling capacity from power is dramatic. Of course, you can also split the process of storing and releasing of energy which can be an advantage. Last but not least, sodium in its metal form is not hard to store or to transport. At ~100°C it becomes liquid and therefore even easier to transfer using regular steel pipes.
- api 2y ago
  I think you meant more investment but yes. That sodium battery sounds great for grid scale storage and maybe aviation. The major problem with lithium there is weight per kWh. Wouldn’t use it in anything consumer because liquid sodium loves to party.
  - kaliszad 2y ago
    No, I really meant less investment - you don't have to push seamless pipes 10+ km underground for the sodium fuel cell to work. It can literally be built in a garage. Liquid sodium is totally fine unless you pour water over it. You have problems with other substances too and it depends what use case and limits you have whether you are willing to go with sodium. For example, filling a big tank with normal gasoline is dangerous without protective atmosphere and other precautions like good grounding because it tends to produce flammable vapors that catch fire easily. Not a problem with sodium. Also, if you happen to spill sodium into water, it neutralizes quickly doing damage only for a short period of time. That cannot be said about any kind of mineral oil, gasoline that has a tendency to destroy ecosystems etc. Last but not least, you can produce sodium metal without begging mostly totalitarian/ authoritarian regimes for natural resources which is the case with the majority of fossil fuels today. Because of electronics and fine machines we learned a lot about how to make stuff water tight. Sodium is in my opinion mostly much easier to handle than hydrogen, which leaks even through steel, which you have to keep under high pressure to have any kind of decent volumetric energy density or cool to very low temperatures if liquid. If you used sodium for grid scale storage than you would more or less solve the electricity storage problem and most likely quite cheaply. The great thing about it is, you can store and transport sodium metal easily. Storing power for the winter becomes practical. For stationary stuff in homes or businesses you could probably use sodium too. You could replace old central furnaces with it and instead use the fuel cell and a heat pump perhaps with a small battery and PV to smooth out the peaks. That way you probably wouldn't need to upgrade the last mile of the grid in many places. You could power boats with it. For aviation it doesn't seem that great as you would still have to handle the resulting sodium hydroxide.

sfink 2y ago

Dumb question: is there any use for this for horizontal drilling? I'm imagining scaling up the size of the drill head to the size of a car-carrying bore hole, vaporizing the rock (or whatever gets in your way) and using some of it to recondense into tunnel liner, and blowing out the rest of the ash either back out the whole tunnel or via vertical(ish) vent tubes drilled periodically from the tunnel roof up. Though maybe the tunnel liner part is too much of a stretch. It sounds like the vaporized rock wants to turn to ash. I don't know if there's a way of concentrating the once-solid parts and keeping it hot enough while routing it to the tunnel wall. It just seems like a cool set of problems to solve, resulting in a self-contained (minus the energy source) burrowing drill that can create arbitrarily long stone tunnels underneath (non-volcanic) land. DIY lava tubes!

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dylan604 2y ago
The oil&gas industry makes heavy use of horizontal drilling already. Say you own land with a nice pocket of $$$ buried beneath, but you refuse them to put a well on your property. That's when they turn to horizontal drilling. Infamously stated as "if you have a milkshake and I have a milkshake, but I have a straw that reaches your milkshake, then I have all the milkshake".
- bluGill 2y ago
  Modern laws are generally onto this, and if caught (a big if) bad things happen. This is also why oil and gas companies buy mineral rights anywhere they might be interested in - it lets them take your oil without worrying about it. Of course not everyone lives where law is caught up to this, but it is a big deal and so most places where it matters the courts know what is up.
  - njarboe 2y ago
    More like if they buy your mineral rights they now own your oil and have the right to extract it.

greenthrow 2y ago

Inaccurate title. "Finds" implies it is being or has been used. More accurate would be "Fusion tech proposed to be used in geothermal energy drilling."

gzu 2y ago

It's like if only we put more resources towards potential societal altering technologies like these instead of [insert random SAAS app]. Maybe tech investors aren't very comfortable with projects outside their domain knowledge and expect an quick return. Quaise last financing round was something like $20M...

baq 2y ago
one (1) good thing that may come out of OpenAI is thirst for electricity only satiable by fusion, just as demand for heat in UK could only be met by digging deeper for coal which ultimately spurred the industrial revolution.
- m463 2y ago
  and coal mining (kind of) saved the forests and and drilling for oil (kind of) saved the whales.
  - rbanffy 2y ago
    Completely unintended side effect, but coal and oil might have created the need for massive rewilding efforts that might, ultimately not only save the forests, but winding cover back to pre-industrial levels.
- dylan604 2y ago
  what a sad statement on the human condition that all of the other needs for limitless clean power did not meet the needs to justify developing fusion, yet you think that AI will? Jesus wept.
  - tivert 2y ago
    > what a sad statement on the human condition that all of the other needs for limitless clean power did not meet the needs to justify developing fusion, yet you think that AI will? Jesus wept. Well, AI has the promise to provide a supply of loyal slaves to anyone who can afford to pay for the electricity and compute. It's a capitalist's dream: with AI, they may never be forced by necessity to share a single thing with us poors again.

pfdietz 2y ago

Getting deep to hot rocks is important, but reducing the thermal resistance around the borehole is also important. Some schemes fracture the rock between two boreholes, but this requires fiddly positioning of the wells as well as the fractures. Another interesting approach is to increase the thermal conductivity of the rock around a single well. Much of the thermal resistance is in the rock close to the well (as can be seen by examining the relevant integral), so this doesn't have to affect too far out to have a significant effect. A company XGS Energy recently raised $20 M in series "A" funding for this. Their fluid (which is forced into fractures around the borehole) is proprietary, but is thought to contain graphite dust. Graphite can be three orders of magnitude more thermally conductive than rock, so incorporating it into even narrow fractures can have a major effect. https://news.ycombinator.com/item?id=40434975 https://news.ycombinator.com/item?id=40434975 https://jpt.spe.org/hot-rock-slurry-developer-of-emerging-geothermal-tech-readies-for-field-tests https://jpt.spe.org/hot-rock-slurry-developer-of-emerging-ge... (the field tests mentioned there must have been successful, as they raised that $20 M subsequently.) Because this technology involves a single well that remains sealed from the surrounding formation, it could be used in existing played-out oil or gas wells, some of which go quite deep (although that's in basins with low geothermal gradients or else the fossil fuels would have been destroyed.)

baking 2y ago
The $20M is for the field test which starts in July in California. https://techcrunch.com/2024/05/21/special-mud-helps-xgs-energy-get-more-power-out-of-geothermal-wells/ https://techcrunch.com/2024/05/21/special-mud-helps-xgs-ener...
- pfdietz 2y ago
  Useful, thanks.

drtgh 2y ago

Has anyone calculated how much energy could be extracted before the cooling of the earth's crust, due such geothermal extraction, would turn irreversible the reservoir and unleash worse consequences than those "greenhouse gasses" mentioned? From how such progressive temperature change (extraction) would affect the dynamics of the Earth's core, among other things, to how it would affect such temperature to the nature chemical processes on the surface, how it would affect vegetal life (cultives), and so on. The planet is big, but we are talking about, lets say, a century of use or more. Has anyone calculated were would be the limit of holes (on geothermal a new hole each XX years due area cold down) before the "we never guessed that X could happen"?

JoeAltmaier 2y ago
Pretty sure the numbers are not comparable, not by many zeroes. Like, trillions of times more energy in the Earth's heat than humans could extract in a billion years. Add to that, Earth is heated by deep radioactive elements. A fission furnace. Not gonna burn out for a billion years, maybe not ever.
lukan 2y ago
- new heat is generated constantly in the earth by radioactive decay - how much is debated, but this alone probably dwarfs humans energy needs (the core of the earth is really, really BIG) The real danger is in creating local earth quakes, because that already happened.
- pfdietz 2y ago
  Actually, it's estimated radioactive decay in the Earth is about 20 TW, which is also about equal to the current global rate of primary energy consumption. Geothermal can be better described as heat mining than it would be exploiting a steady state heat flow.
- xeonmc 2y ago
  So essentially : - fusion - power of the Sun - fission - power of the Earth

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goda90 2y ago

> which itself yields no greenhouse gasses Does anyone know how much of the atmosphere's heat comes from geothermal energy as opposed to solar radiation? By extracting geothermal energy we'd be increasing that effect in the short term, but would it even be significant?

lainga 2y ago
0.087 W/m^2. Compare to 340 W/m^2 insolation. [] https://en.wikipedia.org/wiki/Earth%27s_energy_budget#Earth's_internal_heat_sources_and_other_minor_effects https://en.wikipedia.org/wiki/Earth%27s_energy_budget#Earth'...
- kokanee 2y ago
  Interesting stuff, particularly the estimation that 140 TW of solar radiation are captured by photosynthesis. In arguments about the efficacy of tree-planting as a climate control effort, I've heard about the effect on albedo radiation and of course on the sinking of CO2, but I've never heard it pointed out that photosynthesis itself captures solar radiation that would otherwise be reflected heat.

peter_d_sherman 2y ago

I have often thought that in the future, there'd be a machine that you could scoop raw earth into (like "Mr. Fusion" in the movie "Back To The Future II") -- any kind of raw earth -- and the machine would automatically separate the raw earth into its constituent elements... Now, such a device would probably seem a little bit far fetched... But the first step in making such a device, if it could ever be engineered, would be to melt the inserted raw earth into a hot liquid state. (From this hot liquid state further chemical refinement processes could be completed, such as scooping out heavier elements from the bottom and lighter elements from the top of the liquid. Any emitted gasses could be captured and cooled down, liquified, etc. From there further chemical refinement processes of the liquids could take place, ultimately resulting in refined Elements being output...) This technology -- the ability to "melt rocks" (aka, the ability to melt raw earth, any raw earth notwithstanding its chemical composition) might just enable the taking of that first step to creating such a machine... Such a machine, should it ever exist, would find great application on Mars in the future, should it ever be able to get there... Anyway, I wish this company a lot of luck in their endeavors!

toss1 2y ago

This seems to have tremendous potential, and not just for geothermal! However, one issue with geothermal that I didn't see addressed is that iirc, geothermal systems start out great, but as water/fluid is pumped down and back up hot, minerals rapidly deposit themselves on the plumbing and decrease the system efficiency and ultimately kill it. Could this system be used to more quickly, cheaply, and regularly perform maintenance, or is this just one good step to get broad geothermal applications, and that remains a problem to be solved? It's be great to hear from any experts in the field - thx!