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Can someone explain to me the advantages of fusion over fission? Except for the radioactive wastes and the enthusiasm of journalists I don't get it

• nucpal 6y ago
  It's mainly the waste. Nuclear fission is a stable source of energy that does not produce carbon emissions in production. It's pretty much the answer to the climate crisis except that it produces dangerous waste that is horrendous to store and manage. Fusion mainly avoids this :)
  • pfdietz 6y ago
    Fusion has been touted as avoiding waste and fuel availability problems of fission. But the main problem of fission is that it's too damned expensive, with very large capital cost. Fusion makes this main problem worse, not better.
  • lambdatronics 6y ago
    Also, the accident scenarios are not as bad -- there's less total radioactivity in the device, and there's no meltdown risk.
    • pfdietz 6y ago
      If you had a fission reactor with a power density as low as a fusion reactor, it would be incredibly safe also. All that thermal inertia, accidents would go in extreme slow motion. You might ask why fission reactors aren't designed that way.
      • lambdatronics 6y ago
        Interesting question. NuScale (https://en.wikipedia.org/wiki/NuScale_Power https://en.wikipedia.org/wiki/NuScale_Power) reactor appears to have a very low power density around 1.5 MW/m^3, by my estimate (2.7m dia, 20m tall, 60MWe -> 180MWth). They still rely on having coolant (water) present in the reactor to avoid a meltdown, although it should circulate automatically by boiling & condensing. The trick is that something like 10% of a fission reactor's thermal output continues for many hours due to decay heat, whereas with a fusion reactor that can be orders of magnitude less, with appropriate material choices.
  • pl-94 6y ago
    OK but some models of gen iv of nuclear power plants can pretty much do the same. It sounds pretty dumb to me that journalists are super enthusiast about fusion but much less about gen iv (which is way more mature)
    • nucpal 6y ago
      "some models of gen iv of nuclear power plants can pretty much do the same" I'd be interested to know which fission plants make fuel recycling and waste disposal trivial, I could make a lot of money! In reality, even the gen 4 plants that have interesting approaches to reprocessing still produce a lot of harmful radioactive waste. Not all the fuel can be recycled and the process itself is imperfect and messy.