Re:Air pollution is worse than we thought
by RangerScience on Thursday August 13, 2020 @02:50PM
(#24146814)
Cool, thanks for the corrections. I learned a bit about this for a single semester a decade ago, so I'm not surprised my knowledge is incomplete and warped by time.
Re:Air pollution is worse than we thought
by speedgoose on Thursday August 13, 2020 @02:49PM
(#24146807)
SuperPhénix was cool on paper but I'm actually surprised that they built it and after that it took so long to stop it. It used sodium, a lot of it, which explodes violently in contact of water.
That's an issue for most people. The political pressure was huge to stop the project. The CEA wasn't even that good at manipulating sodium, they got two known major incidents in Cadarache. One quite spectacular with a huge cloud of fire.
I think nuclear power is great to research and the risk is sometimes worth it, but SuperPhénix was too risky.
The issues with sodium are manageable, as seen in other sodium-cooled reactors like the Russian BN-XXX or the US EBR-II. Sodium has other good properties which make up for the downsides, which is why most fast reactor designs have chosen sodium has the coolant.
They also reprocess their spent fuel, but due to complicated sciency reasons you can only do that a few times when you're burning it in thermal reactors.
France had plans to move to a closed cycle, which would improve fuel utilization by a couple of orders of magnitude, but their breeder reactor program (required for the closed cycle) has largely stalled (see Phenix, SuperPhenix, and ASTRID which was recently cancelled before it even got off the drawing board).
And no, breeder reactors per se aren't about making weapons-grade material except in the feverish dreams of Greenpeace.