4 ms·

AFAIK modern reactor designs do a lot to solve the long-term storage issues; from what I remember France uses a series of different reactor designs, combined wi

AFAIK modern reactor designs do a lot to solve the long-term storage issues; from what I remember France uses a series of different reactor designs, combined with reprocessing, that result in a small amount of waste that's only a problem for 60-70 years. The kind of reactor most people think of (again, AFAIK) are breeder reactors, or otherwise derived from breeder reactors, which were about making weapons-grade material rather than power, which is part of the reason those designs have the issues everyone (largely legitimately) has with them.

notJim 6y ago
What is the state of the world with these modern reactor types? Are they in use anywhere, or still limited to research experiments?
- jabl 6y ago
  The Russians have a couple of them in production (BN-600 & Bn-800) and another being planned (BN-1200). They work fine, but with current uranium prices there's not much reason to do breeding and reprocessing. It's good that we research these, but there is no pressing need to take them into use soon.
jabl 6y ago
No, France uses light water reactors, just like the rest of the world. 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.
- speedgoose 6y ago
  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.
  - jabl 6y ago
    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.
- RangerScience 6y ago
  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.
fuoqi 6y ago
IIRC the idea behind BN reactors is that single such reactor would "burn" waste from 2-3 VVER reactors and recycled by BN fuel would be loaded back to them. So you would install a number of BNs in Russia and supply recycled fuel back to exported reactors. Not only you will save money on fuel (well, assuming nuclear fuel will cost more than it does today), but also will reduce amount of nuclear waste for long-term storage (today most of waste from exported reactors has to come back to Russia).

notJim 6y ago

What is the state of the world with these modern reactor types? Are they in use anywhere, or still limited to research experiments?

jabl 6y ago
The Russians have a couple of them in production (BN-600 & Bn-800) and another being planned (BN-1200). They work fine, but with current uranium prices there's not much reason to do breeding and reprocessing. It's good that we research these, but there is no pressing need to take them into use soon.

jabl 6y ago

No, France uses light water reactors, just like the rest of the world. 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.

speedgoose 6y ago
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.
- jabl 6y ago
  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.
RangerScience 6y ago
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.

fuoqi 6y ago

IIRC the idea behind BN reactors is that single such reactor would "burn" waste from 2-3 VVER reactors and recycled by BN fuel would be loaded back to them. So you would install a number of BNs in Russia and supply recycled fuel back to exported reactors. Not only you will save money on fuel (well, assuming nuclear fuel will cost more than it does today), but also will reduce amount of nuclear waste for long-term storage (today most of waste from exported reactors has to come back to Russia).