10 ms·

Dispatchable energy sir.

by BuffaloBagel 4y ago

kragen 4y ago
conventional nuclear isn't dispatchable ramp times are measured not in hours but in days
- wyaeld 4y ago
  Completely false Modern LWR reactors ramp at around 5% per minute. France & Germany use them for Load following https://en.wikipedia.org/wiki/Load-following_power_plant#Nuclear_power_plants https://en.wikipedia.org/wiki/Load-following_power_plant#Nuc... Conventional nuclear is vastly more dispatchable than other fuel types
  - Schroedingersat 4y ago
    When capex costs more than other technologies plus storage, and it reduces your neutron economy and thus the life of your fuel it's just curtailment with extra steps.
  - pydry 4y ago
    Physically they can ramp down to 50% but generation is pretty much a sunk cost at that point so it makes the bad economics even worse. That would mean that you are paying of the order of $240/MWh instead of $120/MWh. For comparison solar/wind are about $30-40. Levelizing with pumped storage pushes that up to $60-$70. IIRC France and Germany almost exclusively use gas for load following. Even at current prices it's vastly cheaper than using a NPP to do it.
- robocat 4y ago
  Incorrect. NuScale appears to be designed to be dispatchable - for example here is a simulated load-following curve during a day: https://www.researchgate.net/figure/Example-of-NuScale-module-load-following-to-compensate-for-generation-from-the-Horse_fig4_295114246 https://www.researchgate.net/figure/Example-of-NuScale-modul... From: https://www.researchgate.net/publication/295114246_Integrating_nuclear_and_renewables https://www.researchgate.net/publication/295114246_Integrati... The NuScale plant incorporates unique features that enhance its ability to load follow, either due to changes in electricity demand or variable generation by renewable sources on the grid. This is accomplished through a combination of the small unit capacity of a NuScale module (50 MWe gross) and a multi-module approach to the plant design. This design strategy provides a uniquely scalable plant and gives the plant owner considerable flexibility in both the build-out of the plant and also its operation, including for load-following. The key power management options of the NuScale plant for load-following operations, designated NuFollow™, include the following: • Taking one or more modules offline for extended periods of low grid demand or sustained wind output, • Maneuvering reactor power for one or more modules during intermediate periods to compensate for hourly changes in demand or wind generation, or • Bypassing the module’s steam turbine directly to the condenser for rapid responses to load or wind generation variations. One problem is that the US regulatory agency doesn’t like load-following - apparently only one nuclear reactor in the states does it. It is common in European countries to do some load-following on time periods of hours to 2 days (although like all generation technologies, there are limitations and constraints). A section about France on the topic: https://www.world-nuclear.org/information-library/country-profiles/countries-a-f/france.aspx#ECSArticleLink5 https://www.world-nuclear.org/information-library/country-pr...
  - kragen 4y ago
    thank you for the update, this does seem to be a real difference between nuscale and conventional nuclear
  - Schroedingersat 4y ago
    If you're paying $80/MWh for captial and fixed O&M and $20/MWh for fuel and variable O&M, then you're still payiny 80% for the energy you don't produce. At that point it's effectively just curtailment.
    - robocat 4y ago
      And with wind and solar, you need storage, which costs a lot and similarly is is not used most of the time. That said, in New Zealand the story is different, because we have some very large battery banks called hydropower lakes. However when our batteries run dry, the country has a bad time. Currently storage is over 3TWh[1] and in 2020 NZ hydro generated 24TWh[2]. [1] https://www.energylink.co.nz/publications/hydro-watch https://www.energylink.co.nz/publications/hydro-watch [2] https://wikipedia.org/wiki/Electricity_sector_in_New_Zealand https://wikipedia.org/wiki/Electricity_sector_in_New_Zealand
      - midasuni 4y ago
        Storage is needed every night with solar.
        lostlogin 4y ago
        That was the parents opening sentence. Their point is interesting. If you already have hydro and add solar or wind, can you pump back into the lakes during periods of excess, and use the hydro at night?
        midasuni 4y ago
        The opening sentence was “is is not used most of the time”
- Schroedingersat 4y ago
  Not sure if nuscale is wanting to do it in the short term, but many of the SMR concepts include a thermal storage component. This helps build industry experience with molten salts and would allow it to be actually dispatchable (rather than paying for energy in the form of capex and fixed O&M and then just not producing it)
epistasis 4y ago
There are very few locations where renewables have high enough penetration for dispatchability to be the slightest concern for new additions. In locations with lots of renewables already, new projects are including storage, cost-effectively, which turns non-disparchable power into dispatchable. I think it's pretty clear that $58/MWh was never going to be achieved, and as with most nuclear projects, reality is 1.5x-3x of what the boosters promise. But even $58/MWh is not cheap enough to match the bids seen for dispatchable renewables+storage.
- AtlasBarfed 4y ago
  And, consider that the new projects won't be online for 5-10 years, during which time year-on-year improvements to cost of solar and wind will likely continue to decline 5-15% per year. Nuclear projects are turtles chasing rabbits at this point, and the rabbit has head start.
  - midasuni 4y ago
    Nuclear was a great solution back in the 90s and early 00s. Not effective now - the cost in both time and money means it’s not worthwhile.
  - Manuel_D 4y ago
    Except where the part where the rabbit start saturating markets during peak production. Then further progress starts to crawl as less and less of the actual generation capacity is usable. At least not until a breakthrough makes energy storage feasible. The only countries that have successfully moved all or nearly-all of their electricity to decarbonized sources have done so primarily with dispatchable sources: hydroelectricity (E.g. Norway, Brazil, Albania, Uruguay) and with a mix of nuclear power filling in where hydro isn't enough (France, Sweden, Switzerland). All of those countries generate a single digit percentage of their electricity from fossil fuels. Nobody has decarbonized primarily through a source of decarboinzed energy source besides hydroelectricity or nuclear power.* Unless there's a storage breakthrough on the horizon, we'll still need to derive a significant chunk of our electricity generation from dispatchable sources. * One minor counterexample is geothermal power, but like hydro it's geographically dependent.

Dispatchable energy sir.

kragen 4y ago

conventional nuclear isn't dispatchable ramp times are measured not in hours but in days

wyaeld 4y ago
Completely false Modern LWR reactors ramp at around 5% per minute. France & Germany use them for Load following https://en.wikipedia.org/wiki/Load-following_power_plant#Nuclear_power_plants https://en.wikipedia.org/wiki/Load-following_power_plant#Nuc... Conventional nuclear is vastly more dispatchable than other fuel types
- Schroedingersat 4y ago
  When capex costs more than other technologies plus storage, and it reduces your neutron economy and thus the life of your fuel it's just curtailment with extra steps.
- pydry 4y ago
  Physically they can ramp down to 50% but generation is pretty much a sunk cost at that point so it makes the bad economics even worse. That would mean that you are paying of the order of $240/MWh instead of $120/MWh. For comparison solar/wind are about $30-40. Levelizing with pumped storage pushes that up to $60-$70. IIRC France and Germany almost exclusively use gas for load following. Even at current prices it's vastly cheaper than using a NPP to do it.
robocat 4y ago
Incorrect. NuScale appears to be designed to be dispatchable - for example here is a simulated load-following curve during a day: https://www.researchgate.net/figure/Example-of-NuScale-module-load-following-to-compensate-for-generation-from-the-Horse_fig4_295114246 https://www.researchgate.net/figure/Example-of-NuScale-modul... From: https://www.researchgate.net/publication/295114246_Integrating_nuclear_and_renewables https://www.researchgate.net/publication/295114246_Integrati... The NuScale plant incorporates unique features that enhance its ability to load follow, either due to changes in electricity demand or variable generation by renewable sources on the grid. This is accomplished through a combination of the small unit capacity of a NuScale module (50 MWe gross) and a multi-module approach to the plant design. This design strategy provides a uniquely scalable plant and gives the plant owner considerable flexibility in both the build-out of the plant and also its operation, including for load-following. The key power management options of the NuScale plant for load-following operations, designated NuFollow™, include the following: • Taking one or more modules offline for extended periods of low grid demand or sustained wind output, • Maneuvering reactor power for one or more modules during intermediate periods to compensate for hourly changes in demand or wind generation, or • Bypassing the module’s steam turbine directly to the condenser for rapid responses to load or wind generation variations. One problem is that the US regulatory agency doesn’t like load-following - apparently only one nuclear reactor in the states does it. It is common in European countries to do some load-following on time periods of hours to 2 days (although like all generation technologies, there are limitations and constraints). A section about France on the topic: https://www.world-nuclear.org/information-library/country-profiles/countries-a-f/france.aspx#ECSArticleLink5 https://www.world-nuclear.org/information-library/country-pr...
- kragen 4y ago
  thank you for the update, this does seem to be a real difference between nuscale and conventional nuclear
- Schroedingersat 4y ago
  If you're paying $80/MWh for captial and fixed O&M and $20/MWh for fuel and variable O&M, then you're still payiny 80% for the energy you don't produce. At that point it's effectively just curtailment.
  - robocat 4y ago
    And with wind and solar, you need storage, which costs a lot and similarly is is not used most of the time. That said, in New Zealand the story is different, because we have some very large battery banks called hydropower lakes. However when our batteries run dry, the country has a bad time. Currently storage is over 3TWh[1] and in 2020 NZ hydro generated 24TWh[2]. [1] https://www.energylink.co.nz/publications/hydro-watch https://www.energylink.co.nz/publications/hydro-watch [2] https://wikipedia.org/wiki/Electricity_sector_in_New_Zealand https://wikipedia.org/wiki/Electricity_sector_in_New_Zealand
    - midasuni 4y ago
      Storage is needed every night with solar.
      - lostlogin 4y ago
        That was the parents opening sentence. Their point is interesting. If you already have hydro and add solar or wind, can you pump back into the lakes during periods of excess, and use the hydro at night?
        midasuni 4y ago
        The opening sentence was “is is not used most of the time”
Schroedingersat 4y ago
Not sure if nuscale is wanting to do it in the short term, but many of the SMR concepts include a thermal storage component. This helps build industry experience with molten salts and would allow it to be actually dispatchable (rather than paying for energy in the form of capex and fixed O&M and then just not producing it)

epistasis 4y ago

There are very few locations where renewables have high enough penetration for dispatchability to be the slightest concern for new additions. In locations with lots of renewables already, new projects are including storage, cost-effectively, which turns non-disparchable power into dispatchable. I think it's pretty clear that $58/MWh was never going to be achieved, and as with most nuclear projects, reality is 1.5x-3x of what the boosters promise. But even $58/MWh is not cheap enough to match the bids seen for dispatchable renewables+storage.

AtlasBarfed 4y ago
And, consider that the new projects won't be online for 5-10 years, during which time year-on-year improvements to cost of solar and wind will likely continue to decline 5-15% per year. Nuclear projects are turtles chasing rabbits at this point, and the rabbit has head start.
- midasuni 4y ago
  Nuclear was a great solution back in the 90s and early 00s. Not effective now - the cost in both time and money means it’s not worthwhile.
- Manuel_D 4y ago
  Except where the part where the rabbit start saturating markets during peak production. Then further progress starts to crawl as less and less of the actual generation capacity is usable. At least not until a breakthrough makes energy storage feasible. The only countries that have successfully moved all or nearly-all of their electricity to decarbonized sources have done so primarily with dispatchable sources: hydroelectricity (E.g. Norway, Brazil, Albania, Uruguay) and with a mix of nuclear power filling in where hydro isn't enough (France, Sweden, Switzerland). All of those countries generate a single digit percentage of their electricity from fossil fuels. Nobody has decarbonized primarily through a source of decarboinzed energy source besides hydroelectricity or nuclear power.* Unless there's a storage breakthrough on the horizon, we'll still need to derive a significant chunk of our electricity generation from dispatchable sources. * One minor counterexample is geothermal power, but like hydro it's geographically dependent.