http://forums.somethingawful.com/showth ... id=3262710
This is mainly about ITER.
- High-power gyrotrons to generate ~200 GHz waves reliably and efficiently, for electron cyclotron heating (ECH) of the plasma
- Mirrors that can reflect ECH waves while not getting cloudy from neutron damage
- A reliable system to detect and mitigate major disruptions
- A way to get in and repair broken parts in the machine when it's been neutron-activated by the fusion reaction going on inside
All of these things are being actively worked on in fusion research labs. But there is a lot of development left to be done. I'll post more about this later, because it's really important, but there is a huge gulf between even ITER, which runs for about 10 minutes at a time, to a true reactor, which has to run at 10 times the power density of ITER, and for a year at a time with no interruptions.
Here is some interesting backstory about "technology" vs. "science". At one time, the fusion research program in the U.S. was run out of the Department of Energy's, well, energy program. Then, in the mid-1990s, the world basically decided they'd just about had enough of the broken promises from the various fusion research programs. This led to the cancellation of the entire Canadian program, and nearly did in the U.S. as well. The only way it was saved was by moving its 'home' within the government funding system to the DOE Office of Science; the same agency that funds particle accelerators like Fermilab.
Thus the fusion research program became a "science" project rather than an "energy" project. Everyone working on it still does it because it might one day solve our energy problems, but the program no longer had to justify itself to Congress in terms of progress towards actually making energy. When this happened, funding for basic science was ramped up, and for "fusion technology" like magnets, almost completely cancelled. So in the U.S. there has been very little development of practical fusion technology for the last 15 years; most of that stuff is now being developed in Europe, Korea, and Russia. American labs have made phenomenal progress forward on understanding plasma physics issues (transport, stability, etc.) but haven't focussed as much lately. on actually engineering parts for a reactor.