Polywell update from May - sounds like things are going really well!

[OKIsItJustMe]

46. You really ought to say what you mean then

Producing fuel for a Thorium reactor is not as easy a task as it is made out to be by its supporters, nor is its product as clean:

http://world-nuclear.org/info/inf62.html

[font face=Serif][font size=5]Thorium[/font][font size=3]

• Thorium is more abundant in nature than uranium.
• It is fertile rather than fissile, and can be used in conjunction with fissile material as nuclear fuel.
• Thorium fuels can breed fissile uranium-233.

The use of thorium as a new primary energy source has been a tantalizing prospect for many years. Extracting its latent energy value in a cost-effective manner remains a challenge, and will require considerable R&D investment.

...

[font size=2]* The high cost of fuel fabrication is due partly to the high level of radioactivity that builds up in U-233 chemically separated from the irradiated thorium fuel. Separated U-233 is always contaminated with traces of U-232 which decays (with a 69-year half-life) to daughter nuclides such as thallium-208 that are high-energy gamma emitters. Although this confers proliferation resistance to the fuel cycle by making U-233 hard to handle and easy to detect, it results in increased costs. There are similar problems in recycling thorium itself due to highly radioactive Th-228 (an alpha emitter with two-year half life) present.[/font]

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Meanwhile hydrogen-boron fusion may be even better than we thought.

http://research.duke.edu/blog/2011/03/extra-alphas-fusion-energy

[font face=Serif]March 31, 2011

[font size=5]Overturned scientific explanation may be good news for nuclear fusion[/font]

[font size=3]Flat out wrong.

That’s what a team of Duke researchers has discovered, much to its surprise, about a long-accepted explanation of how nuclei collide to produce charged particles for electricity – a process receiving intense interest lately from scientists, entrepreneurs and policy makers in the wake of Japan’s nuclear crisis.

Plasma physicists have been trying for 25 years to create electricity from the fusion of boron and hydrogen atoms.

The new study says their efforts have been based on a misunderstanding of the underlying physics – although the error could end up actually helping those looking to fusion energy as an alternative energy source.

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http://dx.doi.org/10.1016/j.physletb.2010.12.015