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Some years ago, likely around 2010, I had the priviledge to visit Culham Centre for Fusion Energy (it was called UKAEA Culham back then). During my visit, we we

Some years ago, likely around 2010, I had the priviledge to visit Culham Centre for Fusion Energy (it was called UKAEA Culham back then). During my visit, we were shown around various experiments and after a long evening, we had the opportunity to attend a Q&A with the staff. The question everyone wanted to know the answer to was When will it be ready? The scientists and everyone else involved honestly thought 10 years would be more than enough time for the technology to mature and find its way into everyday lives. We are not quite there yet.

willis936 7y ago
I’ve heard the argument that it’s a matter of money rather than time. The physics is such that a big device is a good choice. Even the compact designs based on high field HTS coils will need to overcome their high power density in the divertor, that hasn’t come up much yet but it will. So we want a big device to figure out divertors and breeding and managing instabilities. Great. We’ll a just make the one, ITER. Well we’re still waiting. If someone with a lot of money wanted it to happen Right Now they could. You just need a 40 billion dollar c(r)ash program.
- pfdietz 7y ago
  That argument simply assumes money will solve the problems with fusion. There's very good reason to think it won't.
  - willis936 7y ago
    And that reason is? I have very good reason to think it will, as do the plasma physicists who work on magnetic confinement.
    - pfdietz 7y ago
      The volumetric power density of fusion reactors is inherently lower than fission reactors, because of the square cube law and the need for the fusion reactor to radiate it's output through the wall of the reactor. This means th e nuclear core of the fusion reactor will be both much larger and much more complex than a fission reactor.
      - willis936 7y ago
        Certainly a fusion reactor will be a large, expensive, and complicated device. If it’s going to be directly compared to fission solely on cost to generate power then yes fission is less expensive. The allures of fusion is its lack of ability to meltdown, global abundance of fuel, and the ability to choose what elements get activated. That seems like things that add value to me, but I don’t think the conversations on funding fusion research are at that level. I’ve read the transcripts of the US House Subcommittee on Science, Space, and Technology’s discussions on fusion energy science. It’s clear that the politicians that represent fusion scientists when the budget is made don’t have a strong grasp of what the devices are, their potential impact, the realistic failure modes for these projects, etc. It’s simply a game of politics.
        pfdietz 7y ago
        You are repeating the hoary old argument for fusion. That argument depended on it competing only against fission, and making grand nebulous claims that environmental and safety credits would let it pull ahead, even though it was otherwise more expendive than fission. But fission has now lost to renewables, which are now at a levelized cost 3-4x lower than fission. Fusion's putative safety/env benefits mean nothing now. The program now is existing on institutional inertia. I don't see this coming to anything but an inglorious end.
        DennisP 7y ago
        Wind/solar aren't that cheap if you include enough storage to get through a windless night, and enough overcapacity to get through cloudy winter weeks. If you're backing them up with fossil, then sure, they're pretty darn cheap.
        pfdietz 7y ago
        You back them up with short term storage and hydrogen. With plausible costs for 2030 a CO2-free grid optimizes to 0% nuclear.

willis936 7y ago

I’ve heard the argument that it’s a matter of money rather than time. The physics is such that a big device is a good choice. Even the compact designs based on high field HTS coils will need to overcome their high power density in the divertor, that hasn’t come up much yet but it will. So we want a big device to figure out divertors and breeding and managing instabilities. Great. We’ll a just make the one, ITER. Well we’re still waiting. If someone with a lot of money wanted it to happen Right Now they could. You just need a 40 billion dollar c(r)ash program.

pfdietz 7y ago
That argument simply assumes money will solve the problems with fusion. There's very good reason to think it won't.
- willis936 7y ago
  And that reason is? I have very good reason to think it will, as do the plasma physicists who work on magnetic confinement.
  - pfdietz 7y ago
    The volumetric power density of fusion reactors is inherently lower than fission reactors, because of the square cube law and the need for the fusion reactor to radiate it's output through the wall of the reactor. This means th e nuclear core of the fusion reactor will be both much larger and much more complex than a fission reactor.
    - willis936 7y ago
      Certainly a fusion reactor will be a large, expensive, and complicated device. If it’s going to be directly compared to fission solely on cost to generate power then yes fission is less expensive. The allures of fusion is its lack of ability to meltdown, global abundance of fuel, and the ability to choose what elements get activated. That seems like things that add value to me, but I don’t think the conversations on funding fusion research are at that level. I’ve read the transcripts of the US House Subcommittee on Science, Space, and Technology’s discussions on fusion energy science. It’s clear that the politicians that represent fusion scientists when the budget is made don’t have a strong grasp of what the devices are, their potential impact, the realistic failure modes for these projects, etc. It’s simply a game of politics.
      - pfdietz 7y ago
        You are repeating the hoary old argument for fusion. That argument depended on it competing only against fission, and making grand nebulous claims that environmental and safety credits would let it pull ahead, even though it was otherwise more expendive than fission. But fission has now lost to renewables, which are now at a levelized cost 3-4x lower than fission. Fusion's putative safety/env benefits mean nothing now. The program now is existing on institutional inertia. I don't see this coming to anything but an inglorious end.
        DennisP 7y ago
        Wind/solar aren't that cheap if you include enough storage to get through a windless night, and enough overcapacity to get through cloudy winter weeks. If you're backing them up with fossil, then sure, they're pretty darn cheap.
        pfdietz 7y ago
        You back them up with short term storage and hydrogen. With plausible costs for 2030 a CO2-free grid optimizes to 0% nuclear.