Talk-Polywell.org

Very interesting presentation about how new REBCO HTSCs affect the outlook for nuclear fusion reactors. This is about Tokamaks but the technology developments affect all magnetic confinement reactor designs. Dennis Whyte briefly mentions other magnetic confinement devices and talks about them quite positively.
Even Tokamaks seem to become more attractive with this. It certainly is worth watching. The future of fusion seems to look brighter than ever.
https://www.youtube.com/watch?v=KkpqA8yG9T4

It is interesting, how similar Tokamak Energy's approach is to ARC/SPARC approach by the MIT. Who copied from whom?
http://nextbigfuture.com/2016/05/compac ... .html#more

This may be a naive question, but why can't we simply update an existing Tokamak test reactor, like JET with REBCO HTSCs? They seem to be compact enough to replace traditional magnetic coils. It seems to me that this would be a much quicker way to demonstrate the increased efficiency these REBCO HTSCs promise than to build an all new test reactor with all the things needed to operate it. IF (!), they work as well as MIT and TE seem to expect, then JET could probably beat ITER in terms of fusion output. So why is no one proposing it? Am I missing something?

Skipjack wrote:It is interesting, how similar Tokamak Energy's approach is to ARC/SPARC approach by the MIT. Who copied from whom?
http://nextbigfuture.com/2016/05/compac ... .html#more

I couldn't say definitively, but Tokamak Energy does list Professor Dennis Whyte as a consultant. He also features in two videos on Tokamak Energy's YouTube channel.

Oh duh! Its the same guy! Guess they are somehow cooperating on this

Dennis Whyte and MIT have updated their ARC design. At the same size, they have now been able to increase the fusion power to 1 GW. Great lecture on youtube explaining design details of the ARC. I am NOT a huge fan of Tokamaks, but Prof. Whyte and his students at the MIT have done a fantastic job at designing a tokamak that could be feasible (and economic) as a commercial reactor.
https://www.youtube.com/watch?v=RkpIVBAxBS4

I just watched one of Prof. Whyte's videos - very impressive. (I'm looking forward to seeing the other one.) He makes the point that the REBCO superconductor allows higher fields which allow a Tokamak to be made much smaller, which greatly reduces the cost and construction time. Would the same hold true for a polywell?

Both machine would also breed tritium from lithium. In ARC, the lithium blanket takes the form of a molten salt, FLIBE, which also acts as coolant and (damage-resistant) radiation shielding. The polywell could use the same method, right?

(Prof. Whyte also liked the higher magnetic field because it made the plasma more stable, but the polywell field curvature already provides stability. He also liked the new REBCO superconductor because the coils could be made demountable, but I don't think that's helpful for a polywell because there's no need to access the inside of the coil.)

jrvz wrote:I just watched one of Prof. Whyte's videos - very impressive. (I'm looking forward to seeing the other one.) He makes the point that the REBCO superconductor allows higher fields which allow a Tokamak to be made much smaller, which greatly reduces the cost and construction time. Would the same hold true for a polywell?

Both machine would also breed tritium from lithium. In ARC, the lithium blanket takes the form of a molten salt, FLIBE, which also acts as coolant and (damage-resistant) radiation shielding. The polywell could use the same method, right?

(Prof. Whyte also liked the higher magnetic field because it made the plasma more stable, but the polywell field curvature already provides stability. He also liked the new REBCO superconductor because the coils could be made demountable, but I don't think that's helpful for a polywell because there's no need to access the inside of the coil.)

It is my understanding that most magnetic confinement concepts and also magneto- inertial confinement will benefit as well, at what rate depends on the scheme, though. Some may be limited by engineering considerations. One of the limiting factors for the size of that ARC is/was the neutron flux. The improvements to the design that came with the new divertor allowed them to go to further improve on that though. They were able to double the output without increasing the size.

There is a materials issue for high T. Lots of stress between the coils, and on the vessel from the coils. There are also cooling issues, and at high T's weird things can start happening to fluids and components. Everything is magnetic, you just don't always see it until you get high enough T.

I also seem to recall there is some issue with machine dynamics. Can't put my finger on it right now, and could be wrong.

In general, for Polywell, more T is better.