MIT's simple ARC reactor for nuclear fusion power plants

in environment on 2015-12-02 10:46 (#WCZ9)

Advances in magnet technology have enabled researchers at MIT to propose a new design for a practical compact tokamak fusion reactor. MIT's new reactor is named as the ARC reactor.

Rare-earth barium copper oxide (REBCO) superconducting tapes are the enabling technology behind the ARC reactor. When it is cooled to liquid nitrogen temperature, the superconducting tape can carry as much current as the large copper conductor, enabling the construction of extremely high"field magnets, which consume minimal amounts of power.
https://www.youtube.com/watch?v=O3ECJSEeW_A&list=PLK2ccNIJVPpB_XqWWq_oaZGIDzmKiSkYc

http://www.techtimes.com/articles/76112/20150812/tiny-fusion.htm

tokamak's vs Stellarators (Score: 1)

by billshooterofbul@pipedot.org on 2015-12-07 17:27 (#WYCJ)

It kind of seems odd to me to miniaturize a design that hasn't worked well enough even at large scales. But maybe the physics works out like semiconducters where efficiency is gained with smaller size ( possibly less energy input needed? ).

As an alternative, I'd like to see more research put into Stellarators. Take these super conductors and put them into both, see which works better with them. Oh and we'll need twice the research money for that. But we'll get more than two results!

https://en.wikipedia.org/wiki/Stellarator

No evidence that it does shit to address the real problem (Score: 1)

by fnj@pipedot.org on 2015-12-08 13:48 (#X1C6)

As far as I know, the reason Tokamaks have consistently failed for over 50 years has nothing to do with them being too large and expensive. Dozens of them have been tried, many very extensively. In all cases, nobody has figured out how to solve the exceedingly difficult problem of maintaining stable confinement for more than milliseconds. Confinement takes more than just a simple toroidal magnetic field.

There are other problems, huge ones, but until some progress is made on this overriding one, we are just stumbling helplessly in the dark.

I assume that many if not all Tokamaks have used superconducting magnets. You don't run currents of millions of amperes through copper. Not for long (more than milliseconds). Even if you had enough copper to carry it and enough refrigeration to keep the copper from melting, losses would be collossal.

Re: No evidence that it does shit to address the real problem (Score: 1)

by billshooterofbul@pipedot.org on 2015-12-08 15:26 (#X1NG)

Well, yes confinement is a huge issue, and obviously all other tokamaks have used superconducting magnets, this uses high temp ( well liquid nitrogen is considered high temp) ones that reduced the energy needed to keep them cool. Less input energy should mean that getting to a point where they put out more energy than they take in should be easier. I thinkthat's the significance here.

But yeah, huge problems like confinement remain. I'm so disappointed that NIF didn't work. Although, in retrospect, I wonder if it was ever supposed to work for non weapons reasons.