[ExI] nuclear fusion

[John K Clark]

Keith wrote:

>it's [fusion] incredibly dangerous. The problem is
> any neutron source can be diverted into making
> extremely high grade plutonium.

Oh I don't know, I think the cat is already out of the bag. Right know there
are hundreds, probably thousands of tons of Plutonium on the planet,
I'm not sure a little more would make things significantly more dangerous
than they are now.

Damien Broderick Wrote:

  > From fusion reactors?

Yes. Most of the energy produced in a deuterium-tritium reaction is in the
form of high speed neutrons; if you pack common cheap U238 around a
fusion reactor then you've got yourself a Plutonium factory. Even without
the U238 these neutrons would cause problems with magnetic confined
fusion as they would make the entire machine radioactive and cause
mechanical weakness in the parts. This would be less of a concern for
LASER inertial confinement fusion and no problem at all if you used a
deuterium-helium 3 reaction, but there's not much helium 3 on Earth
(although there's plenty in comets and in the outer moons) and you'd
need ever higher temperature and pressure than in the D-T reaction.

  John K Clark