Reply To: Repowering the electric utility industry

[Joeviocoe]

Thanks for the explanation James.

jamesr wrote:
Todd Rider’s thesis http://dspace.mit.edu/handle/1721.1/11412 and subsequent work, showed that this bremsstrahlung issue effectively rules out all other fusion fuels except D+T, D+D, and D+He-3, and furthermore for nett gain has to be at or near thermal equilibrium. This is partly why I don’t believe any of the other innovative concepts such as polywells will work. However Rider did not take account of the effect of the quantization of electron cyclotron orbits in very strong magnetic fields http://en.wikipedia.org/wiki/Landau_quantization. This limits the transfer of energy from the fast ions to the electrons, and effectively keeps the electron temperature much lower than the ion temperature. Even so it is a tall order to reach the extreme fields needed to reduce the key collision parameter known as the Coulomb Logarithm from the
standard value of 15-20 beyond even Rider’s most optimistic value of 5.

Does the Polywell concept not achieve magnetic fields in the GigaGauss range? What parameter(s) are needed in a Focus Fusion device to achieve the needed field strength?