4 ms·

> It's actually much better quality of power plant than nuclear because it can be scaled up and down throughout the day economically... It's not that nuclear

> It's actually much better quality of power plant than nuclear because it can be scaled up and down throughout the day economically... It's not that nuclear reactors can't be built to vary their output. It's that nuclear power is almost all fixed cost. If the average power level over a year is 50%, the power cost doubles. Geothermal has similar economics.

caminante 2y ago
Geothermal isn't cheap. Trimming those fixed costs means siting on fault lines/earthquakes and higher opex (insurance). Fervo/Google got dogged for announcing their plant in UT because they avoided disclosures about the capacity [0]. It's more of a very small scale pilot of a couple MWs, but they buried key facts about the project assumedly on purpose due to lack of significance. [0] https://blog.google/outreach-initiatives/sustainability/google-fervo-geothermal-energy-partnership/ https://blog.google/outreach-initiatives/sustainability/goog...
- micro2588 2y ago
  Fervo's initial demonstration project was next to an existing power plant in Nevada which previously failed to produce at it's stated capacity over time (Battle Mountain) so they were able to tie in extra MWt capacity to an existing ORC turbine. Fervo's technology has to be located somewhat near existing traditional hydrothermal geothermal resources because it's the convection along an exiting fault for hundreds of thousands of years that produces an above background thermal gradient near enough to the surface for it to be economical. That is true for their demonstration area in Utah which is located near the existing Blundel geothermal power plant in Milford Utah.
  - caminante 2y ago
    Sure. Exposing these situational constraints and free benefits (third-party sunk costs) aligns with my stance. I don't agree with the above comment: > Fervo isn't just trying, they are succeeding
    - micro2588 2y ago
      I think as a tech demonstration project it was successful because they were a bit conservative in some ways that will make the economics look worse. I agree it's far from "geothermal everywhere" which seems to be the hype. You can't extrapolate that from one successful EGS well literally right next to an existing geothermal power plant.
      - caminante 2y ago
        > they were a bit conservative in some ways that will make the economics look worse Or they simply ran into headwinds on a speculative project. I'll "take the under" when your PR is cagey about basic project attributes.
        micro2588 2y ago
        They do a good job of publishing their results in technical industry publications (advancing the field overall in a surprisingly open way) but I agree can be misleading in their marketing. It will be interesting to see the results of the Cape project once they do multi-well laterals from a single pad power plant with larger diameter wells. That is really more a demonstration of power plant economics beyond the technical feasibility of creating a horizontally fracked reservoir that can be operated for a year.
        caminante 2y ago
        Ah! Cape Station does look much more significant. [0] 400MW of power plant capacity with 2028 COD and mostly contracted with SoCal Edison? Good job. [0] https://www.utilitydive.com/news/cape-station-enhanced-geothermal-utah-fervo-blm-lease/726796/ https://www.utilitydive.com/news/cape-station-enhanced-geoth...
epistasis 2y ago
Not quite, with geothermal the storage is built into the system by simply limiting the intake, which builds pressure and can shift energy production throughout the day. The cost of enhanced geothermal is roughly the exact same cost as nuclear today (if you exclude the very high cost of failed build attempts for nuclear), and it shares similar economics of a very very low OpEx to CapEx ratio. However the economics differ massively in that enhanced geothermal is getting cheaper as we build more, but nuclear tends to get more expensive as we build more. Geothermal is a technology, nuclear is a monument.
- TheSpiceIsLife 2y ago
  > Not quite … The cost of enhanced geothermal is roughly the exact same cost as nuclear … shares similar economics of a very very low OpEx to CapEx ratio. It can’t be both not quire and the same. All else being equal, a five billion dollar geothermal plant running at 50% has the same problem as a five billion dollar nuclear plant running at 50%: where’s my profit? Sure, load following is trivial with geothermal, but nuclear generally isn’t trying to compete in that space, so we can discount the difference there.
  - epistasis 2y ago
    Unlike nuclear, that time running at 50% isn't thrown away capital expense, it is merely delayed power output that can be utilized with slightly higher turbine capacity, which is the cheaper part of the capex, and would be needed for higher power output anyway. For nuclear, adding thermal storage for time shifting would be the most equivalent to what's happening with geothermal storage, but with geothermal there's no additional capex or engineering needed.
    - TheSpiceIsLife 2y ago
      > that time running at 50% isn't thrown away capital expense I don’t understand how you think capex works? You outlay x on capital expenses to get the plant running, that’s all the plant and equipment. You run the plant at 50% it takes you twice as long to recoup your capex. Always happy to be corrected.
s1artibartfast 2y ago
My understanding of that most nuclear power plants currently operating can already scale up and down to match demand. They don't because I fuel costs are so low that the power is essentially free when compared to idling.
- jabl 2y ago
  That's correct. There's nothing technically special about the French nuclear plants that load follow. It's just that France has so much nuclear power in the grid that some of their nuclear plants do load following.
brrt 2y ago
Have you heard about xenon poisoning? Load following with a nuclear power plant is much more complex than it seems
- jonkoops 2y ago
  This already makes a large assumption about the type of reactor you are using. For example, a liquid fluoride thorium reactor (LFTR) does not suffer from the xenon poisoning issue, as do many other designs.
  - jncfhnb 2y ago
    I don’t believe there are any commercial LFTR plants?
    - lillecarl 2y ago
      It's an interesting thing that pro-nuclear people always talk about "Gen X" power plats with no issues and just a big fat gogo stamp on them, but when you ask about any commercial examples they all come up short. I'm pro nuclear, but I don't think using hypotheticals and futures is how to convince people nuclear is good, it's good because it works and it doesn't poison the planet (Yes there have been accidents and they have been dramatised but count deaths and it becomes as irrational as being afraid of flying)
      - cogman10 2y ago
        It takes decades to turn on a new plant which is why you won't see the latest and greatest commercially deployed anytime soon.
        rtkwe 2y ago
        Molten Salt reactors are designs from the 60s-70s and afaik no one ever built on commercially. No one was willing to take a gamble on building a new design when we had working reactors already and approval for those was already difficult enough.
Dennip 2y ago
Can't you just burn up the power, e.g. with water->hydrogen conversion, water desalination, pumped hydro, etc. Whenever the grid isn't demanding 100% for your power you throw it at some other profit-generating venture. Granted you then have to built of of those power-using-things and only run it when grid demand drops.
- pyrale 2y ago
  > e.g. with [...] pumped hydro That's done a lot in France, but there's a limited amount of pumped hydro available in the end. Until recently, countries with lots of available nuclear energy didn't really need to produce fresh water, and non-gas-produced hydrogen is still a WIP.
- alach11 2y ago
  > Can't you just [store the power] If you find a cheap solution to power storage, you can make a lot of money. This is the key enabler for a 100% renewable grid.
  - EasyMark 2y ago
    you'd be the first trillionaire.
  - Dennip 2y ago
    We already do electricity -> hydrogen generation, the hydrogen is then stored in underground pumped storage (empty gas wells), and can be used in place of natural gas. Although presumably if you set up one of these facilities you need it running 24/7 to be profitable not just when there is a lull in demand elsewhere.
- not_wyoming 2y ago
  Relatedly, I've read a couple of neat articles on using mine shafts as gravity batteries: https://bigthink.com/the-future/coal-mines-gravity-battery-energy-storage/ https://bigthink.com/the-future/coal-mines-gravity-battery-e... Major footnote here that I'm wayyyy out of my wheelhouse on this stuff, so there may be reasons that this doesn't work. I invite correction if that's the case so we can all learn some stuff :)
scythe 2y ago
>Geothermal has similar economics. Doesn't the ground itself act as an energy reservoir for geothermal? I haven't looked this one up, but it definitely seems like geothermal should be very dispatchable.
lupusreal 2y ago
Nuclear reactors can indeed be made to adjust their power level very quickly, but this typically requires the use of highly enriched uranium which introduces new costs and problems.

caminante 2y ago

Geothermal isn't cheap. Trimming those fixed costs means siting on fault lines/earthquakes and higher opex (insurance). Fervo/Google got dogged for announcing their plant in UT because they avoided disclosures about the capacity [0]. It's more of a very small scale pilot of a couple MWs, but they buried key facts about the project assumedly on purpose due to lack of significance. [0] https://blog.google/outreach-initiatives/sustainability/google-fervo-geothermal-energy-partnership/ https://blog.google/outreach-initiatives/sustainability/goog...

micro2588 2y ago
Fervo's initial demonstration project was next to an existing power plant in Nevada which previously failed to produce at it's stated capacity over time (Battle Mountain) so they were able to tie in extra MWt capacity to an existing ORC turbine. Fervo's technology has to be located somewhat near existing traditional hydrothermal geothermal resources because it's the convection along an exiting fault for hundreds of thousands of years that produces an above background thermal gradient near enough to the surface for it to be economical. That is true for their demonstration area in Utah which is located near the existing Blundel geothermal power plant in Milford Utah.
- caminante 2y ago
  Sure. Exposing these situational constraints and free benefits (third-party sunk costs) aligns with my stance. I don't agree with the above comment: > Fervo isn't just trying, they are succeeding
  - micro2588 2y ago
    I think as a tech demonstration project it was successful because they were a bit conservative in some ways that will make the economics look worse. I agree it's far from "geothermal everywhere" which seems to be the hype. You can't extrapolate that from one successful EGS well literally right next to an existing geothermal power plant.
    - caminante 2y ago
      > they were a bit conservative in some ways that will make the economics look worse Or they simply ran into headwinds on a speculative project. I'll "take the under" when your PR is cagey about basic project attributes.
      - micro2588 2y ago
        They do a good job of publishing their results in technical industry publications (advancing the field overall in a surprisingly open way) but I agree can be misleading in their marketing. It will be interesting to see the results of the Cape project once they do multi-well laterals from a single pad power plant with larger diameter wells. That is really more a demonstration of power plant economics beyond the technical feasibility of creating a horizontally fracked reservoir that can be operated for a year.
        caminante 2y ago
        Ah! Cape Station does look much more significant. [0] 400MW of power plant capacity with 2028 COD and mostly contracted with SoCal Edison? Good job. [0] https://www.utilitydive.com/news/cape-station-enhanced-geothermal-utah-fervo-blm-lease/726796/ https://www.utilitydive.com/news/cape-station-enhanced-geoth...

epistasis 2y ago

Not quite, with geothermal the storage is built into the system by simply limiting the intake, which builds pressure and can shift energy production throughout the day. The cost of enhanced geothermal is roughly the exact same cost as nuclear today (if you exclude the very high cost of failed build attempts for nuclear), and it shares similar economics of a very very low OpEx to CapEx ratio. However the economics differ massively in that enhanced geothermal is getting cheaper as we build more, but nuclear tends to get more expensive as we build more. Geothermal is a technology, nuclear is a monument.

TheSpiceIsLife 2y ago
> Not quite … The cost of enhanced geothermal is roughly the exact same cost as nuclear … shares similar economics of a very very low OpEx to CapEx ratio. It can’t be both not quire and the same. All else being equal, a five billion dollar geothermal plant running at 50% has the same problem as a five billion dollar nuclear plant running at 50%: where’s my profit? Sure, load following is trivial with geothermal, but nuclear generally isn’t trying to compete in that space, so we can discount the difference there.
- epistasis 2y ago
  Unlike nuclear, that time running at 50% isn't thrown away capital expense, it is merely delayed power output that can be utilized with slightly higher turbine capacity, which is the cheaper part of the capex, and would be needed for higher power output anyway. For nuclear, adding thermal storage for time shifting would be the most equivalent to what's happening with geothermal storage, but with geothermal there's no additional capex or engineering needed.
  - TheSpiceIsLife 2y ago
    > that time running at 50% isn't thrown away capital expense I don’t understand how you think capex works? You outlay x on capital expenses to get the plant running, that’s all the plant and equipment. You run the plant at 50% it takes you twice as long to recoup your capex. Always happy to be corrected.

s1artibartfast 2y ago

My understanding of that most nuclear power plants currently operating can already scale up and down to match demand. They don't because I fuel costs are so low that the power is essentially free when compared to idling.

jabl 2y ago
That's correct. There's nothing technically special about the French nuclear plants that load follow. It's just that France has so much nuclear power in the grid that some of their nuclear plants do load following.

brrt 2y ago

Have you heard about xenon poisoning? Load following with a nuclear power plant is much more complex than it seems

jonkoops 2y ago
This already makes a large assumption about the type of reactor you are using. For example, a liquid fluoride thorium reactor (LFTR) does not suffer from the xenon poisoning issue, as do many other designs.
- jncfhnb 2y ago
  I don’t believe there are any commercial LFTR plants?
  - lillecarl 2y ago
    It's an interesting thing that pro-nuclear people always talk about "Gen X" power plats with no issues and just a big fat gogo stamp on them, but when you ask about any commercial examples they all come up short. I'm pro nuclear, but I don't think using hypotheticals and futures is how to convince people nuclear is good, it's good because it works and it doesn't poison the planet (Yes there have been accidents and they have been dramatised but count deaths and it becomes as irrational as being afraid of flying)
    - cogman10 2y ago
      It takes decades to turn on a new plant which is why you won't see the latest and greatest commercially deployed anytime soon.
      - rtkwe 2y ago
        Molten Salt reactors are designs from the 60s-70s and afaik no one ever built on commercially. No one was willing to take a gamble on building a new design when we had working reactors already and approval for those was already difficult enough.

Dennip 2y ago

Can't you just burn up the power, e.g. with water->hydrogen conversion, water desalination, pumped hydro, etc. Whenever the grid isn't demanding 100% for your power you throw it at some other profit-generating venture. Granted you then have to built of of those power-using-things and only run it when grid demand drops.

pyrale 2y ago
> e.g. with [...] pumped hydro That's done a lot in France, but there's a limited amount of pumped hydro available in the end. Until recently, countries with lots of available nuclear energy didn't really need to produce fresh water, and non-gas-produced hydrogen is still a WIP.
alach11 2y ago
> Can't you just [store the power] If you find a cheap solution to power storage, you can make a lot of money. This is the key enabler for a 100% renewable grid.
- EasyMark 2y ago
  you'd be the first trillionaire.
- Dennip 2y ago
  We already do electricity -> hydrogen generation, the hydrogen is then stored in underground pumped storage (empty gas wells), and can be used in place of natural gas. Although presumably if you set up one of these facilities you need it running 24/7 to be profitable not just when there is a lull in demand elsewhere.
not_wyoming 2y ago
Relatedly, I've read a couple of neat articles on using mine shafts as gravity batteries: https://bigthink.com/the-future/coal-mines-gravity-battery-energy-storage/ https://bigthink.com/the-future/coal-mines-gravity-battery-e... Major footnote here that I'm wayyyy out of my wheelhouse on this stuff, so there may be reasons that this doesn't work. I invite correction if that's the case so we can all learn some stuff :)

scythe 2y ago

>Geothermal has similar economics. Doesn't the ground itself act as an energy reservoir for geothermal? I haven't looked this one up, but it definitely seems like geothermal should be very dispatchable.

lupusreal 2y ago

Nuclear reactors can indeed be made to adjust their power level very quickly, but this typically requires the use of highly enriched uranium which introduces new costs and problems.