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Construction of French Fusion Reactor Underway
GarryFre writes "It has been said that fusion is 50 years away for quite a few decades, but now work has actually been started. Digging has begun in the south of France on the planned site for France's first fusion reactor. A tokomak is a torus shaped magnetic confinement device which is necessary to withstand the temperatures associated with fusion that are so high, solid materials can't hold them. As such, the building represents the future core of ITER (International Thermonuclear Experimental Reactor.) It will be interesting to see if it takes 50 years to build it."
That eternal "Fusion is 50 years away" saying stopped being due to physics and started being due to squabbling countries and their bureaucracies many years ago. ITER could have been started over a decade ago.
Free the Quark 3 from asymptotic confinement! Bring your charm! Don't get down! All colours and flavours welcome!
The whole point of ITER was to "demonstrate" that the science is settled. Apparently "the science" is fully settled. Nevertheless they've made several serious design flaws, and are seriously behind schedule (and below expected results for what they've done too). Nevertheless, they're charging ahead, and all smart people hope they succeed.
Btw, there are fusion reactors in most large hospitals, for neutron production. They're called "fusors" and they're basically a rolled up television display. Additionally these (very simple) devices are used for scientific research in most universities. They're very reliable, but have Q levels around 0.1 up to 0.3 for professionally constructed ones.
Imho, I think the American research plan is smarter than the European one. At the very least for the simple fact that Europe is throwing all their eggs in the same (proven to be somewhat unreliable) basket. America may be underfunding fusion research, absolutely, but at least America's underfunding 5 different attempts (including steam-based fusion, my favorite). But there are others, and there are even hybrid machines (meant to do research and to produce fusion, e.g. Z-pinch, or the Z-machine). Also there are several American tokamaks, just in case that's the solution after all.
The tokamak approach banks on pushing back to all forces that act on a fusing plasma, and it's like placing 2000000 small propellors on the ground to control a raging thunderstorm. I'm not saying it will never work, but I'll be utterly amazed. There are other approaches. Hydrogen bombs, on the plus side, they're proven to be effective. On the downside ... well ask some pacific ex-islands ... they know. Then there's inertial confinement fusion, where you generate a number of (relatively) small forces that converge on the same point. For a short time, huge forces will act on this small point, generating fusion. Steam-based fusion is an example, but so is laser fusion, and essentially Z-pinch too. There's also the polywell, an evolution of the only type of fusion rector in commercial use, the fusor, which is a fusor with a magnetic field to replace the fusor grids (google "should google go nuclear ?"). There's even a few attempts that involve principles that boil down to shooting high pressure gas in what's essentially a funnel, resulting in huge pressures just behind the end of the funnel. And I don't really understand how the Z-pinch is supposed to work.
I went to a talk from a fusion proponent recently who was involved with ITER, and had worked on fusion for most of his career. His view is that the media obsess over break even, and don't understand the reasons they've not hit it. His explanation was that they know how to get to break even now, but that wouldn't make for a usable reactor, as the cost of enegy production would be just too high if you're only just past that threshold. Also the cost of hitting break even now is considerably more than not hitting it. So instead of wasting lots of money hitting break even for a headline, they're trying to sort the issues they know to exist that are stopping them from being considerably more efficient than break even.
There were people on ITER who wanted it to be connected up to the grid, so that if they surpass break even (which they expect to), they'd be able to get a considerable PR coup. Problem is, hooking it up would have added considerably to the costs, which given how much it's overrun could have ended up killing the project.
jh