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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."
It may well be physically in France, I wouldn't call it French per se. The I in the name most assuredly stands for International, with technical and financial input from around the world (China, the EU, India, Japan, Korea, Russia, and the USA, in alphabetical order).
It's a project we all may ultimately depend on as a civilisation, so the International part is important.
the world's first Fusion Reactor
http://en.wikipedia.org/wiki/Farnsworth-Hirsch_Fusor
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
SPELLING FAIL.
Dog is my co-pilot.
Shame about the whole 3 strikes business and kicking the Roma's out of the country...
People replying to my sig annoy me. That's why I change it all the time.
Actually, ITER is intended to demonstrate a useful amount of energy production from fusion. It's baseline design is for Q=10, i.e. 10 times more power out from fusion than put in. This is essentially a feasibility demonstration, and experimental test bed for things like wall modules and blankets. The follow-on (DEMO) will then be a prototype power plant, and actually be connected up to generators etc.
ps. though AC, also a plasma physicist working on tokamaks
There are two main reasons why it is thought that ITER can achieve more power out than in (10 times more in fact)
1. It is about 8 times the plasma volume of JET (about 2x in each direction). The temperature gradients in tokamaks have limits (things like Ion Temperature Gradient mode-driven turbulence) so the bigger you make the machine the hotter you can make the middle of the plasma and the better your performance. The problem with this is that the power output goes like the volume, but the area this power is deposited on goes like the area. Hence why small fusion plants would be nice, and materials are the biggest issue for ITER and DEMO
2. They will be using Tritium in ITER. Tokamaks today have only very rarely used tritium (e.g. JET, JT60-U) to produce more power out than in (very briefly 1s). This is because the plasma physics doesn't really change when you add Tritium, so experiments use Deuterium which is much cheaper and less dangerous (e.g. radioactive). At 100 million degrees, the D-D fusion rate is still pretty small and so the amount of fusion energy produced is tiny. The D-T rate is orders of magnitude higher and so significant power can be produced
p.s. Yes, AC plasma physicist
Fortunatly the magnetic confinement techniques they'll be using doesn't fail at any particular temperature. RTFM!
Which is still a tiny bit short of the 100,000,000K that they're looking at. http://en.wikipedia.org/wiki/Iter#Reactor_overview.
I said it earlier and I'll say it again: this is *not* a French reactor. It may be physically based in France, but it's an international endeavour. There's already a tokamak in operation, located in England and operated by the whole EC: it's called JET, for "Joint European Torus".