Thanks advancednano ... some good links there.

Tell me, when you say the Thorium cycle "can" breed fuel grade U233 - what is the energy economics of that process ? ... is it a process that should be promoted irrespective of the available Uranium sources ?

Is that CANDU / AECL Thorium cycle really just R&D stage, or is there proven (economically viable) breeder technology from UK's previous "fast breeder" technology ?

http://www.britannica.com/eb/article-81620/thorium-processing

When bombarded by thermalized neutrons (usually released by the fission of uranium-235 in a nuclear reactor), thorium-232 is converted to thorium-233. This isotope decays to protactinium-233, which in turn decays to uranium-233.

http://thoriumenergy.blogspot.com/2006/06/latest-developments-on-u-233-s...

If you get a mass of uranium 235 or plutonium or some other source of thermalized neutrons and put it with the thorium then you initiate the reactions which lead to uranium 233.

http://thoriumenergy.blogspot.com is the place to learn more.