12 ms·

> The more there is, the cheaper it gets. This also applies to nuclear fusion (and, BTW, fission) reactors.

by joss82 5y ago

ncmncm 5y ago
Tokamak fusion can only ever be far more expensive, per watt and per watt-hour, than existing fission. Fission is getting more expensive all the time.
- chmod775 5y ago
  > Tokamak fusion can only ever be far more expensive, per watt and per watt-hour, than existing fission. Why?
  - ncmncm 5y ago
    The energy flux density in the most compressed plasma imaginable is orders of magnitude less than in fissile uranium. So, to match power out, it has to be big. Really, really big. And a fusion reaction chamber is a much more expensive affair than a fission pile: super high-tech materials and construction, enormous magnets (blasted by the hot-neutron flux output), piping for thousands of tons of melted lithium that have to be replaced (by robots! because super radioactive) every couple of years as the neutrons destroy them. The (radioactive) lithium itself, and containment for if it breaks out of the piping. Continuous processing of the lithium to extract synthetic tritium for fuel. Heat exchangers for lithium to a working fluid that won't pick up radioactivity, and more heat exchangers from that to water for steam. And then the usual steam turbines, which demand regular, very expensive maintenance. Cooling towers to condense the steam, after. A hundred billion dollars estimated for one several GW plant, and decades for construction. Meanwhile, solar and wind get cheaper every year, with no bottom in sight. The longer they take on fusion, the less competitive it gets, and it starts out way behind, with no possibility of ever catching up.
    - _0w8t 5y ago
      This was with previous designs of fusion reactors. Read about proposed Ark and currently constructing Spark reactors. By using stronger superconductive magnets it was possible to reduce the size of the plant by order of magnitude. Spark even has a chance to get to Q>1 before ITER and it’s chamber is less than 2m in diameter. Plus it is possible to replace its parts without disassembling the whole reactor. [1] - https://en.m.wikipedia.org/wiki/SPARC_(tokamak) https://en.m.wikipedia.org/wiki/SPARC_(tokamak)
      - ncmncm 5y ago
        That might be nice if they had solutions to the other problems not addressed (see above). But operating it will necessarily still be enormously more expensive than solar or wind, which cost practically nothing. Somebody with one leg can do a lot better in a race than somebody with none, but that is not the measure to consider when the competition is with two-legged runners. (Hint: they win.)
        _0w8t 5y ago
        In Europe after the last autumn when for months there were little wind and cloudy sky there is a realization that energy based purely on renewables will require much bigger storage and much more solar or at least significantly more expensive solar that works under clouds. Doable, but cost is non-trivial. So if any of fusion startups can make operating plant within the next 20 years, it can be used. But if that takes longer, then I agree that large-scale fusion will not happen.
        pfdietz 5y ago
        Long term darkness/calm is solved with hydrogen. Europe has plenty of underground geology suitable for mass hydrogen storage (it's just like natural gas is stored.) Most of the energy still would go directly from solar/wind to the grid, or through efficient batteries, so the low round trip efficiency of power to gas to power doesn't matter much.
- rob74 5y ago
  I'm not that familiar with the subject, but this phrase sounds suspiciously like the 1943 IBM executive saying there is a market for only five computers in the world - i.e. it completely discounts technological progress. Of course, this progress has been painfully slow until now, but comparing it with fission is still unfair - fission is well-researched and it getting more expensive is tied to the inherent dangers of radioactivity (and the ever more complicated measures which try to mitigate them), and the costs of spent fuel storage.
  - ncmncm 5y ago
    Fission getting more expensive is tied to the very lucrative fully-legal corruption industry. Once a fission plant construction project is started, the money starts flowing, and is practically impossible to stop. If it is ever finished, the money would stop, and nobody actually involved wants that ever to happen, at least not until their kids graduate college. So the project blows through deadline after deadline, and cost overruns pile up without limit, until somebody manages to pull the plug. Once it looks like the money will stop regardless, there is some incentive to deliver a reactor; we saw that in Finland recently. South Carolina is the more typical cancellation after billions are spent, except in that case with a few indictments. Normally nobody gets indicted, and nobody ever has to give any money back.
    - hallway_monitor 5y ago
      Wow this is brutal but feels like it's correct. What a frightening state of affairs. Is the construction industry really so corrupt? Is government and industry unaware or unwilling/unable to detect this earlier and stop it?
      - hunter-gatherer 5y ago
        I spent some fair amount of years as both a government employee in DoD and then some years as a defense contractor amd I can tell you the military industrial complex is a real thing. In my contracting days I worked with a handful of DoE engineers that were more familiar with reactor projects and as I understood it, reactor peojects basically follow the same type of workflow as any big DoD prohect. So OPs comment is much in line with my understanding of the issue. It is an unfortunate state of affairs.
pfdietz 5y ago
Actually, fission power plants have shown a distressing lack of good experience effects. They got more expensive as more were built, not less expensive.
- vlovich123 5y ago
  Fission did keep getting cheaper up until FUD about accidents and explosions caused regulations that strangled it (that and overblown fears about proliferation of nuclear weapons).
  - pfdietz 5y ago
    Yeah, like all those whiners complaining about how first generation BWR containment was totally inadequate. Never mind what happened at Fukushima, right? /s
    - vlovich123 5y ago
      The amount of accidents and their severity does not line up with the disproportion strangling the technology has experienced at the hands of regulators. If we go down that road, all coal plants should be shut down long ago as they’ve been responsible for more radiation-caused deaths than all nuclear deaths combined (including due to the bombs if I recall correctly). That’s not even counting the deaths they’ve caused through air pollution. Heck, nuclear is still competitive with solar and wind in terms of deaths/MW produced. And this is all the more stark considering nuclear designs stagnated 60 years or so ago. If we hadn’t divested from that technological path we’d have drastically cheaper and safer nuclear energy today and global warming potentially wouldn’t even be a problem.

> The more there is, the cheaper it gets. This also applies to nuclear fusion (and, BTW, fission) reactors.

by joss82 5y ago

> The more there is, the cheaper it gets. This also applies to nuclear fusion (and, BTW, fission) reactors.

Tokamak fusion can only ever be far more expensive, per watt and per watt-hour, than existing fission. Fission is getting more expensive all the time.

chmod775 5y ago
> Tokamak fusion can only ever be far more expensive, per watt and per watt-hour, than existing fission. Why?
- ncmncm 5y ago
  The energy flux density in the most compressed plasma imaginable is orders of magnitude less than in fissile uranium. So, to match power out, it has to be big. Really, really big. And a fusion reaction chamber is a much more expensive affair than a fission pile: super high-tech materials and construction, enormous magnets (blasted by the hot-neutron flux output), piping for thousands of tons of melted lithium that have to be replaced (by robots! because super radioactive) every couple of years as the neutrons destroy them. The (radioactive) lithium itself, and containment for if it breaks out of the piping. Continuous processing of the lithium to extract synthetic tritium for fuel. Heat exchangers for lithium to a working fluid that won't pick up radioactivity, and more heat exchangers from that to water for steam. And then the usual steam turbines, which demand regular, very expensive maintenance. Cooling towers to condense the steam, after. A hundred billion dollars estimated for one several GW plant, and decades for construction. Meanwhile, solar and wind get cheaper every year, with no bottom in sight. The longer they take on fusion, the less competitive it gets, and it starts out way behind, with no possibility of ever catching up.
  - _0w8t 5y ago
    This was with previous designs of fusion reactors. Read about proposed Ark and currently constructing Spark reactors. By using stronger superconductive magnets it was possible to reduce the size of the plant by order of magnitude. Spark even has a chance to get to Q>1 before ITER and it’s chamber is less than 2m in diameter. Plus it is possible to replace its parts without disassembling the whole reactor. [1] - https://en.m.wikipedia.org/wiki/SPARC_(tokamak) https://en.m.wikipedia.org/wiki/SPARC_(tokamak)
    - ncmncm 5y ago
      That might be nice if they had solutions to the other problems not addressed (see above). But operating it will necessarily still be enormously more expensive than solar or wind, which cost practically nothing. Somebody with one leg can do a lot better in a race than somebody with none, but that is not the measure to consider when the competition is with two-legged runners. (Hint: they win.)
      - _0w8t 5y ago
        In Europe after the last autumn when for months there were little wind and cloudy sky there is a realization that energy based purely on renewables will require much bigger storage and much more solar or at least significantly more expensive solar that works under clouds. Doable, but cost is non-trivial. So if any of fusion startups can make operating plant within the next 20 years, it can be used. But if that takes longer, then I agree that large-scale fusion will not happen.
        pfdietz 5y ago
        Long term darkness/calm is solved with hydrogen. Europe has plenty of underground geology suitable for mass hydrogen storage (it's just like natural gas is stored.) Most of the energy still would go directly from solar/wind to the grid, or through efficient batteries, so the low round trip efficiency of power to gas to power doesn't matter much.
rob74 5y ago
I'm not that familiar with the subject, but this phrase sounds suspiciously like the 1943 IBM executive saying there is a market for only five computers in the world - i.e. it completely discounts technological progress. Of course, this progress has been painfully slow until now, but comparing it with fission is still unfair - fission is well-researched and it getting more expensive is tied to the inherent dangers of radioactivity (and the ever more complicated measures which try to mitigate them), and the costs of spent fuel storage.
- ncmncm 5y ago
  Fission getting more expensive is tied to the very lucrative fully-legal corruption industry. Once a fission plant construction project is started, the money starts flowing, and is practically impossible to stop. If it is ever finished, the money would stop, and nobody actually involved wants that ever to happen, at least not until their kids graduate college. So the project blows through deadline after deadline, and cost overruns pile up without limit, until somebody manages to pull the plug. Once it looks like the money will stop regardless, there is some incentive to deliver a reactor; we saw that in Finland recently. South Carolina is the more typical cancellation after billions are spent, except in that case with a few indictments. Normally nobody gets indicted, and nobody ever has to give any money back.
  - hallway_monitor 5y ago
    Wow this is brutal but feels like it's correct. What a frightening state of affairs. Is the construction industry really so corrupt? Is government and industry unaware or unwilling/unable to detect this earlier and stop it?
    - hunter-gatherer 5y ago
      I spent some fair amount of years as both a government employee in DoD and then some years as a defense contractor amd I can tell you the military industrial complex is a real thing. In my contracting days I worked with a handful of DoE engineers that were more familiar with reactor projects and as I understood it, reactor peojects basically follow the same type of workflow as any big DoD prohect. So OPs comment is much in line with my understanding of the issue. It is an unfortunate state of affairs.

pfdietz 5y ago

Actually, fission power plants have shown a distressing lack of good experience effects. They got more expensive as more were built, not less expensive.

vlovich123 5y ago
Fission did keep getting cheaper up until FUD about accidents and explosions caused regulations that strangled it (that and overblown fears about proliferation of nuclear weapons).
- pfdietz 5y ago
  Yeah, like all those whiners complaining about how first generation BWR containment was totally inadequate. Never mind what happened at Fukushima, right? /s
  - vlovich123 5y ago
    The amount of accidents and their severity does not line up with the disproportion strangling the technology has experienced at the hands of regulators. If we go down that road, all coal plants should be shut down long ago as they’ve been responsible for more radiation-caused deaths than all nuclear deaths combined (including due to the bombs if I recall correctly). That’s not even counting the deaths they’ve caused through air pollution. Heck, nuclear is still competitive with solar and wind in terms of deaths/MW produced. And this is all the more stark considering nuclear designs stagnated 60 years or so ago. If we hadn’t divested from that technological path we’d have drastically cheaper and safer nuclear energy today and global warming potentially wouldn’t even be a problem.