3 ms·
> if we reprocessed all spent fuel in the U.S. today, we'd have enough Pu to power about 33 MWe worth of breeders, about 1/3 of the current fleet. That should
by uvdiv 16y ago
> if we reprocessed all spent fuel in the U.S. today, we'd have enough Pu to power about 33 MWe worth of breeders, about 1/3 of the current fleet.
That should be "GWe" not "MWe".
Also, I dispute your choice of statistic. Why not show what happens if you start fast breeders on mined uranium, just like LWRs?
- terra_t 16y agoSorry I missed a factor of 1000. Fast breeders on mined uranium have the same problem as plutonium breeders... Except you can breed plutonium faster (but less efficiently) in LWRs!
- uvdiv 16y agoI mean, it's an odd statistic. You can use U-235 directly, or you can burn it in an LWR, getting back just 1/5th its equivalent in Pu-239, and use that. If you're trying to maximize fissile input for fast breeders, LWR spent fuel isn't an efficient way. And moreover, with mined uranium there's no limit to your rate of expansion other than mining. You don't have to sit and wait for your atoms to reproduce (doubling time 20-40 years), when you can just dig up new ones. Some back of the envelope numbers: Assuming 3% enriched fuel burned to 40 GWd/ton, and 33% thermodynamic efficiency, the US nuclear fleet (~100 GWe) consumes around 100 tons/year of U-235 in fuel. At about 10 kg/MWe fissile inventory, just 10 years' of present US uranium consumption would be enough (1,000 tons) to start up a 100 GWe fleet of fast breeders -- same as the current LWR fleet. I found a table of fissile inventories here: http://nuclear.inl.gov/deliverables/docs/msr_deliverable_doe-global_07_paper.pdf http://nuclear.inl.gov/deliverables/docs/msr_deliverable_doe...