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Old May 20th 06, 04:12 AM posted to sci.space.policy,sci.space.history,sci.space.station
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Default ...Lesson for Nasa! US Airmail and Aviation

In article .com,
Hyper wrote:
...and the limits imposed on fission by uranium supply.


Isn't the problem of supply obviated by using breeder reactors?


If you build the breeder reactors, and the corresponding reprocessing
plants; there are non-trivial political obstacles to doing so, not to
mention some remaining technical issues with existing breeder designs.

And what about the kilotons of U238 in storage?


What about them? U-238 isn't a reactor fuel, not without breeding.

Likely recoverable reserves of U-235 (not counting seawater and granite,
both of which are very difficult to mine economically) correspond to about
300 TW-yr of energy. Unfortunately, world power demand is going to grow
by tens of TW in the next half-century, so that just isn't enough to base
a long-term energy infrastructure on. Breeding -- preferably U-233 from
thorium rather than Pu-239 from U-238 -- would fix that, but it means
restarting breeder-reactor technology work quickly, and then building a
lot of breeder reactors and reprocessing plants in a hurry.
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