6 ms·

In 2040 fusion energy advancements will have gotten far enough to be the next technological step and make this redundant anyway

deleted 11mo ago
[deleted]
epistasis 11mo ago
There's currently no technological path for fusion to be cheaper than fission. It would require a technological breakthrough that we have not yet imagined. And already, solar plus storage is cheaper than new nuclear. And solar and storage are getting cheaper at a tremendous rate. It's hard to imagine a scenario where fusion could ever catch up to solar and storage technology. It may be useful in places with poor solar resources, like fission is now, but that's a very very long time from now.
- BurningFrog 11mo ago
  The regulatory hurdles are probably bigger than the difficult enough technological ones you mention.
- noosphr 11mo ago
  The low energy future that was envisioned is not happening. The AI arms race, which has become an actual arms race in the war in Ukraine, needs endless energy all times a day. China is already winning the AI cold war because it adds more capacity to its grid a year than Germany has in a century. If we keep going with agrarian methods of energy production don't be surprised that we suffer the same fate as the agrarian societies of the 19th century. Any country that doesn't have the capability to train and build drones on mass won't be a country for long.
  - epistasis 11mo ago
    You have that exactly backwards: solar + storage is what will give us energy abundance at less money than we could ever imagine from nuclear fission or fusion. China is winning the AI Cold war because it's adding solar, storage, and wind at orders of magnitude more than nuclear. I'm not sure who's doing your supposed "envisioning" but there is no vision for cheap abundant energy from fusion. Solar and storage deliver it today, fusion only delivers it in sci fi books. Nuclear is 20th century technology that does not fit with a highly automated future. With high levels of automation, construction is super expensive. You want to spend your expensive construction labor on building factories, not individual power generation sites. Building factories for solar and storage lets them scale to a degree that nuclear could never scale. Nuclear has basically no way of catching up.
    - pfdietz 11mo ago
      > sci fi books I blame these for the unquestioned belief that fusion is desirable. It's a trope because it enables stories to be told, and because readers became used to seeing, not because science fiction has a good track record on such things. The fact that the volumetric power density of ARC is 40x worse than a PWR (and ITER, 400x worse!) should tell one that DT fusion at least is unlikely to be cheap. With continued progress down the experience curve, PV will reach the point where resistive heat is cheaper than burning natural gas at the Henry Hub price (which doesn't include the cost of getting gas through pipelines and distribution to customers.) And remember cheap natural gas was what destroyed the last nuclear renaissance in the US.
      - formerly_proven 11mo ago
        It's hard to imagine a form of energy production less desirable than fusion. Okay, sure, burning lignite and using the exhaust as air heating in the children's hospital. You got me.
    - noosphr 11mo ago
      China has been building out nuclear capacity at 5% a year for 25 years. Solar and wind capacity had shot through the roof in the last five years because they can't sell hardware to the west any more. The other big item is hydro power, which China has a ton of untapped potential for. Unfortunately for the West every good river has already been damed so we can't follow them there.
      - epistasis 11mo ago
        > Solar and wind capacity had shot through the roof in the last five years because they can't sell hardware to the west any more. "can't sell hardware??" hah! I've never heard that weird made-up justification, where did you pick it up from? China installed 277GW of solar in 2024, capacity factor corrected that's 55.4 GW of solar power. That's equivalent to the entire amount of nuclear that China has ever built. One year versus all time. And then in the first half of 2025, China installed another 212GW of solar. In six months. Nuclear is a footnote compared to the planned deployment of solar and wind and storage in China. Anybody who's serious about energy is deploying massive amounts of solar, storage, and some wind. Some people that are slow to adapt are still building gas or coal, but these will be stranded assets far before their end of life. Nuclear fusion and fission are meme technologies, unable to compete with the scale and scope that batteries and solar deliver every day. This mismatch grows by the month.
- Dylan16807 11mo ago
  Fission is expensive for regulation reasons more than technological reasons, so if fusion doesn't face the same barriers then it could be cheaper than fission. But I agree that it doesn't look like fusion is going to be cheap any time soon.
  - deleted 11mo ago
    [deleted]
  - bryanlarsen 11mo ago
    Fission is also expensive for several mundane reasons, like the fact that massive steam turbines are expensive, and because any large construction project in the West is expensive. Neither fusion nor regulatory reform are going to solve those.
- apendleton 11mo ago
  > It would require a technological breakthrough that we have not yet imagined. Maybe, but not necessarily. The necessary breakthrough might have been high-temperature superconducting magnets, in which case not only has it been imagined, but it has already occurred, and we're just waiting for the engineering atop that breakthrough to progress enough to demonstrate a working prototype (the magnets have been demonstrated but a complete reactor using them hasn't yet). Or it might be that the attempts at building such a prototype don't pan out, and some other breakthrough is indeed needed. It'll probably be a couple of years until we know for sure, but at this point I don't think there's enough data to say one way or the other. > And already, solar plus storage is cheaper than new nuclear. It depends how much storage you mean. If you're only worried about sub-24h load-shifting (like, enough to handle a day/night cycle on a sunny day), this is certainly true. If you care about having enough to cover for extended bad weather, or worse yet, for seasonal load-shifting (banking power in the summer to cover the winter), the economics of solar plus storage remain abysmal: the additional batteries you need cost just as much as the ones you needed for daily coverage, but get cycled way less and so are much harder to pay for. If the plan is to use solar and storage for _all generation_, though, that's the number that matters. Comparing LCoE of solar plus daily storage with the LCoE of fixed-firm or on-demand generation is apples-and-oranges. I think solar plus storage absolutely has the potential to get there, but that too will likely require fundamental breakthroughs (probably in the form of much cheaper storage: perhaps something like Form Energy's iron-air batteries).
  - deleted 11mo ago
    [deleted]
  - pfdietz 11mo ago
    High temperature superconducting magnets are not a panacea for the problems with DT fusion. Those issues follow from limits on power/area at the first wall, and the needed thickness of the first wall; these ensure DT reactors will have low volumetric power density, regardless of the confinement scheme used. With HTSC magnets, a tokamak much smaller than ITER could be built, but ITER is so horrifically bad that one can be much better than it and still be impractical.
bee_rider 11mo ago
This is like a “fusion is only 20 years away” (or 15 in this case) joke, right?
- hinkley 11mo ago
  It used to be 30. So fifty more years?
  - marcosdumay 11mo ago
    Yep, it was 30 years at the 60s. If it keeps halving every 85 years, we'll get it approximately never :)
    - hinkley 11mo ago
      Zeno's Fusion Paradox
megaman821 11mo ago
The steam generator that the fusion generator connects to might be more expensive than solar at this point. That would be even if fusion cost nothing and had infinite amounts of fuel, there would be no customers for its energy on a sunny afternoon.
throwaway270925 11mo ago
With solar, fusion energy is already here! There is just a bit of wireless transmission involved after generation.

deleted 11mo ago

[deleted]

epistasis 11mo ago

There's currently no technological path for fusion to be cheaper than fission. It would require a technological breakthrough that we have not yet imagined. And already, solar plus storage is cheaper than new nuclear. And solar and storage are getting cheaper at a tremendous rate. It's hard to imagine a scenario where fusion could ever catch up to solar and storage technology. It may be useful in places with poor solar resources, like fission is now, but that's a very very long time from now.

BurningFrog 11mo ago
The regulatory hurdles are probably bigger than the difficult enough technological ones you mention.
noosphr 11mo ago
The low energy future that was envisioned is not happening. The AI arms race, which has become an actual arms race in the war in Ukraine, needs endless energy all times a day. China is already winning the AI cold war because it adds more capacity to its grid a year than Germany has in a century. If we keep going with agrarian methods of energy production don't be surprised that we suffer the same fate as the agrarian societies of the 19th century. Any country that doesn't have the capability to train and build drones on mass won't be a country for long.
- epistasis 11mo ago
  You have that exactly backwards: solar + storage is what will give us energy abundance at less money than we could ever imagine from nuclear fission or fusion. China is winning the AI Cold war because it's adding solar, storage, and wind at orders of magnitude more than nuclear. I'm not sure who's doing your supposed "envisioning" but there is no vision for cheap abundant energy from fusion. Solar and storage deliver it today, fusion only delivers it in sci fi books. Nuclear is 20th century technology that does not fit with a highly automated future. With high levels of automation, construction is super expensive. You want to spend your expensive construction labor on building factories, not individual power generation sites. Building factories for solar and storage lets them scale to a degree that nuclear could never scale. Nuclear has basically no way of catching up.
  - pfdietz 11mo ago
    > sci fi books I blame these for the unquestioned belief that fusion is desirable. It's a trope because it enables stories to be told, and because readers became used to seeing, not because science fiction has a good track record on such things. The fact that the volumetric power density of ARC is 40x worse than a PWR (and ITER, 400x worse!) should tell one that DT fusion at least is unlikely to be cheap. With continued progress down the experience curve, PV will reach the point where resistive heat is cheaper than burning natural gas at the Henry Hub price (which doesn't include the cost of getting gas through pipelines and distribution to customers.) And remember cheap natural gas was what destroyed the last nuclear renaissance in the US.
    - formerly_proven 11mo ago
      It's hard to imagine a form of energy production less desirable than fusion. Okay, sure, burning lignite and using the exhaust as air heating in the children's hospital. You got me.
  - noosphr 11mo ago
    China has been building out nuclear capacity at 5% a year for 25 years. Solar and wind capacity had shot through the roof in the last five years because they can't sell hardware to the west any more. The other big item is hydro power, which China has a ton of untapped potential for. Unfortunately for the West every good river has already been damed so we can't follow them there.
    - epistasis 11mo ago
      > Solar and wind capacity had shot through the roof in the last five years because they can't sell hardware to the west any more. "can't sell hardware??" hah! I've never heard that weird made-up justification, where did you pick it up from? China installed 277GW of solar in 2024, capacity factor corrected that's 55.4 GW of solar power. That's equivalent to the entire amount of nuclear that China has ever built. One year versus all time. And then in the first half of 2025, China installed another 212GW of solar. In six months. Nuclear is a footnote compared to the planned deployment of solar and wind and storage in China. Anybody who's serious about energy is deploying massive amounts of solar, storage, and some wind. Some people that are slow to adapt are still building gas or coal, but these will be stranded assets far before their end of life. Nuclear fusion and fission are meme technologies, unable to compete with the scale and scope that batteries and solar deliver every day. This mismatch grows by the month.
Dylan16807 11mo ago
Fission is expensive for regulation reasons more than technological reasons, so if fusion doesn't face the same barriers then it could be cheaper than fission. But I agree that it doesn't look like fusion is going to be cheap any time soon.
- deleted 11mo ago
  [deleted]
- bryanlarsen 11mo ago
  Fission is also expensive for several mundane reasons, like the fact that massive steam turbines are expensive, and because any large construction project in the West is expensive. Neither fusion nor regulatory reform are going to solve those.
apendleton 11mo ago
> It would require a technological breakthrough that we have not yet imagined. Maybe, but not necessarily. The necessary breakthrough might have been high-temperature superconducting magnets, in which case not only has it been imagined, but it has already occurred, and we're just waiting for the engineering atop that breakthrough to progress enough to demonstrate a working prototype (the magnets have been demonstrated but a complete reactor using them hasn't yet). Or it might be that the attempts at building such a prototype don't pan out, and some other breakthrough is indeed needed. It'll probably be a couple of years until we know for sure, but at this point I don't think there's enough data to say one way or the other. > And already, solar plus storage is cheaper than new nuclear. It depends how much storage you mean. If you're only worried about sub-24h load-shifting (like, enough to handle a day/night cycle on a sunny day), this is certainly true. If you care about having enough to cover for extended bad weather, or worse yet, for seasonal load-shifting (banking power in the summer to cover the winter), the economics of solar plus storage remain abysmal: the additional batteries you need cost just as much as the ones you needed for daily coverage, but get cycled way less and so are much harder to pay for. If the plan is to use solar and storage for _all generation_, though, that's the number that matters. Comparing LCoE of solar plus daily storage with the LCoE of fixed-firm or on-demand generation is apples-and-oranges. I think solar plus storage absolutely has the potential to get there, but that too will likely require fundamental breakthroughs (probably in the form of much cheaper storage: perhaps something like Form Energy's iron-air batteries).
- deleted 11mo ago
  [deleted]
- pfdietz 11mo ago
  High temperature superconducting magnets are not a panacea for the problems with DT fusion. Those issues follow from limits on power/area at the first wall, and the needed thickness of the first wall; these ensure DT reactors will have low volumetric power density, regardless of the confinement scheme used. With HTSC magnets, a tokamak much smaller than ITER could be built, but ITER is so horrifically bad that one can be much better than it and still be impractical.

bee_rider 11mo ago

This is like a “fusion is only 20 years away” (or 15 in this case) joke, right?

hinkley 11mo ago
It used to be 30. So fifty more years?
- marcosdumay 11mo ago
  Yep, it was 30 years at the 60s. If it keeps halving every 85 years, we'll get it approximately never :)
  - hinkley 11mo ago
    Zeno's Fusion Paradox

megaman821 11mo ago

The steam generator that the fusion generator connects to might be more expensive than solar at this point. That would be even if fusion cost nothing and had infinite amounts of fuel, there would be no customers for its energy on a sunny afternoon.

throwaway270925 11mo ago

With solar, fusion energy is already here! There is just a bit of wireless transmission involved after generation.