That "X years away" is a popular trope mainstreamed by Greenpeace & friends, but it's not true.
Fusion is an incredible challenge as it depends on plenty of sectors, such as material engineering, cooling technologies, laser, magnets etc etc, each of which is practically a separate science that is being developed right now.
In case of specific projects such as ITER, it's also equally complicated logistics and supply chains, as it's an international project, currently the most complex organizational and engineering project globally.
It does take a lot of time, because the research is done is a pretty regular schedule. A breakthrough of similar complexity, nuclear fission, has been completed much faster during war time due to mobilization of effort and resources. It's not the case with fusion unfortunately, or fortunately, as we're not at a world war.
The progress is however being made, and it's definitely not an all or nothing situation, because the construction of ITER alone brings plenty of new innovation, and the project is going to run first plasma in 2026. ITER will be the largest fusion device in the world, with Q=10 (the NIL experiment ran ar t Q=1.54) and when it works, both interest and funding should be much accelerated.
I very much recommend a book "ITER: The giant fusion reactor" by Michel Claessens, its former director, a it goes into great details on all these areas.
@rysiek
@kravietz @rysiek @aehnnek@universeodon.com
I completely agree that zero-power nuclear reactors were developed for urgent military reasons. Non-zero-power reactors seem to have been developed for non-urgent military reasons (originally they weren't even targeting submarines) in the US (Rickover and Naval Reactors); I am ignorant about the Soviet counterpart.
Do you think that there was a (perceived?) pressing military need for nuclear propulsion that sped things up, or that the post-war environment was friendly to even foibles entertained by the Navy, or something else?
> and when it works, both interest and funding should be much accelerated.
It seems to me that what should accelerate interest and funding is already _reliable prediction_ of it working. Do you expect that this could happen nontrivially earlier?
Nuclear weapons program in WW2 was a mobilization of science and resources on unprecedented scale, with a very clearly defined goals, and they solved plenty of engineering problems in a very short time, that would otherwise take decades of research at "relaxed" speed.
As for fusion, the prediction is quite certain that it will be working, what the research is focused on is how to make it as cheap as possible (the concepts of "engineering breakeven" and "commercial breakeven"). The plan for ITER is to run first plasma in 2026, but it will be still a research reactor, whose heat will be not used for producing power. But once ITER is live, the member states are expected to start construction of the second stage reactors called START, and these will be electricity producing units.
@rysiek @aehnnek
@kravietz @rysiek @aehnnek@universeodon.com
Nuclear weapons program needed reactors only for plutonium production. The culmination of that effort was Hanford B. Its construction was similar to Windscale: it was a cube with various rods stuck in it cooled with a large flow of water (as opposed to air in Windscale). This is not a design suited to power generation via steam production (if not for any other reason, due to inability to operate at higher internal pressures, due to its construction). Due to its low-pressure-water cooling, it operated at at most ~100degC (measured in outgoing cooling water; fuel elements and graphite core were naturally hotter), so it didn't allow exploration of higher temperatures. It also didn't have various feedback loops that power production plants would have due to e.g. the cooling being a loop (in Hanford B apparently the hot cooling water was discharged into the same river it was taken from).
The reactor research from Hanford B onwards didn't contribute to atomic weapons and IIUC it was clear at that time that no further research was necessary for production of more atomic weapons. And yet first reactors producing power appeared within a few years.
