3 ms·
Isn't the residual heat from normal decay something like 10% of the reactor output? When you split Uranium you get a lot of byproducts with short half-lives th
by Symmetry 9y ago
Isn't the residual heat from normal decay something like 10% of the reactor output? When you split Uranium you get a lot of byproducts with short half-lives that continue decaying away even when Uranium chain reaction stops. So you've still got 40 MW to deal with, at least until those short-half-lived byproducts finish decaying.
- adrianN 9y ago5% for the first few seconds: http://www.euronuclear.org/info/encyclopedia/r/residual-heat.htm http://www.euronuclear.org/info/encyclopedia/r/residual-heat... but your point of course still stands. It's certainly not trivial to build passive-safe reactors, but it's also not impossible.
- vilhelm_s 9y agoAccording to one document[1] > The decay heat produced by a reactor shutdown from full power is initially equivalent to about 5 to 6% of the thermal rating of the reactor. This decay heat generation rate diminishes to less than 1% approximately one hour after shutdown. However, even at these low levels, the amount of heat generated requires the continued removal of heat for an appreciable time after shutdown. At 400 MW it takes about 4 hours to boil the water in an olympic swimming pool[1], so there should be some safety margin for the power to drop. Then once it is down to 1% decay heat it could boil for a couple of weeks before running dry. [1] https://web.archive.org/web/20110316042315/http://www.hss.doe.gov/nuclearsafety/ns/techstds/standard/hdbk1019/h1019v2.pdf https://web.archive.org/web/20110316042315/http://www.hss.do... [2] http://www.wolframalpha.com/input/?i=(specific+heat+of+vaporization+of+water)+*+(2500+m%5E3)+*+(density+of+water)+%2F+400+MW http://www.wolframalpha.com/input/?i=(specific+heat+of+vapor...