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"There was, and is, no intention ever to actually use tokamaks as an electrical-energy source." I thought that's what DEMO which is planned to come after ITER

"There was, and is, no intention ever to actually use tokamaks as an electrical-energy source." I thought that's what DEMO which is planned to come after ITER is for. I have listened to quite a few people working on fusion (ITER, also the people working on Wendelstein-X) and none of them were as negative as you are. Where do all the things you saying come from?

ncmncm 8y ago
DEMO can be postponed indefinitely. Have you heard of any significant investment in maintaining structural integrity of the tokamak itself? Fission reactors need to maintain the integrity of the coolant pipes and the physical supports for the fuel, all just passive structure. I.e., valves, pumps, etc. are behind shielding. It's all just basic physics. And basic politics.
- maxxxxx 8y ago
  Are you saying that all the people working on this this stuff are either idiots or liars? My impression is that there are a ton of problems but they believe they can be solved.
  - ncmncm 8y ago
    The people working on tokamak are engaged in fascinating technical problems, and generally leave politics and practical engineering problems to others. They spent many years getting their particle physics degrees, and have no real job prospects besides this, research accelerators, or direct weapons work. You kind of have to feel sorry for them. There are beginnings of private investment in what might turn out to be practical (i.e. aneutronic) fusion power systems, but they do not seem to need very many physicists.
    - maxxxxx 8y ago
      How do you know all that stuff?
- ben_w 8y ago
  Friend of mine used to work on it. I think, from one of the pub chats we often had, the average number of times each atom in the reactor wall was expected to be knocked out of place by neutron collisions was in the order of 100. This is why I am down on fusion compared to most advocates. On the other hand, I’m also up compared to most pessimists because the everlasting delay looks like it’s caused by an asymptotic-to-zero funding graph. I still have silly ideas about how to improve the efficiency of Farnsworth-type designs — one I’ve never had time to simulate was “can star mode be enhanced with a simple magnetic field, and does it happen in the first place because of the magnetic field created by current flowing between inner and outer grids?”. I had that idea 10 years ago, I hope someone here has more time to sim it than I do.

ncmncm 8y ago

DEMO can be postponed indefinitely. Have you heard of any significant investment in maintaining structural integrity of the tokamak itself? Fission reactors need to maintain the integrity of the coolant pipes and the physical supports for the fuel, all just passive structure. I.e., valves, pumps, etc. are behind shielding. It's all just basic physics. And basic politics.

maxxxxx 8y ago
Are you saying that all the people working on this this stuff are either idiots or liars? My impression is that there are a ton of problems but they believe they can be solved.
- ncmncm 8y ago
  The people working on tokamak are engaged in fascinating technical problems, and generally leave politics and practical engineering problems to others. They spent many years getting their particle physics degrees, and have no real job prospects besides this, research accelerators, or direct weapons work. You kind of have to feel sorry for them. There are beginnings of private investment in what might turn out to be practical (i.e. aneutronic) fusion power systems, but they do not seem to need very many physicists.
  - maxxxxx 8y ago
    How do you know all that stuff?
ben_w 8y ago
Friend of mine used to work on it. I think, from one of the pub chats we often had, the average number of times each atom in the reactor wall was expected to be knocked out of place by neutron collisions was in the order of 100. This is why I am down on fusion compared to most advocates. On the other hand, I’m also up compared to most pessimists because the everlasting delay looks like it’s caused by an asymptotic-to-zero funding graph. I still have silly ideas about how to improve the efficiency of Farnsworth-type designs — one I’ve never had time to simulate was “can star mode be enhanced with a simple magnetic field, and does it happen in the first place because of the magnetic field created by current flowing between inner and outer grids?”. I had that idea 10 years ago, I hope someone here has more time to sim it than I do.