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> No, it's not. Uranium once used in reactor is literally changed to other elements. And the radioactive waste is sealed in container safe for 100s of 1000s of

> No, it's not. Uranium once used in reactor is literally changed to other elements. And the radioactive waste is sealed in container safe for 100s of 1000s of years. Sort of. What you are talking about is a technical problem and it has a solution. (and as others pointed out is not directly related to the subject at hand) Conventional nuclear reactors require a certain level of purity in the uranium to provide stable operation. As the uranium breaks down the fuel becomes less stable. After a while they remove the fuel and then place it into storage. However that uranium is not used up in that process. Most of it is still there. Which is one of the reasons why it's so difficult and expensive to store safely. Theoretically you can recover that fuel in breeder reactors. Essentially recycling it. So it can be re-used in conventional reactors. The breeder reactors will still produce usable electricity as well. And this can be done multiple times. Up to the point were most of the fissionable material is used up and it is much less radioactive and safe to handle. At that point you would combine the waste with clay and bake it into ceramic vessels that can be safely transported and stored indefinitely. The reason why this technology hasn't moved forward is mostly to do with a couple facts. The first one being that nobody is allowed to do anything with the 'waste' as it is Federally controlled and not owned by the power company. So the operators can't do anything with it even if they wanted to. And the second one being that during the cold war USA and other countries created vast amounts of purified uranium as part of their nuclear programs. And they have no place to put it and no use for it other than being put through nuclear reactors. The amount of potentially unlimited power left laying on the table because of politics, paranoia, and fear is mind boggling. If recycling is implemented we currently have many multiple generations worth of fuel stockpiled. It could put a end to the use of fossil fuels used for energy generation within our lifetime. Which is something that is not possible with wind or solar.

Retric 4y ago
That’s basically abusing the word uranium as U235 is used up while U238 is largely not in current designs. Reprocess spent fuel lets you extract the leftover U235, but it’s a small percentage of the original amount. What you want is something like the CANDU design which is far less dependent on U235. https://en.wikipedia.org/wiki/CANDU_reactor https://en.wikipedia.org/wiki/CANDU_reactor
- lazyier 4y ago
  Yeah. I am no expert by any means. I was thinking of something more along the lines of an integral fast reactor were the heavy elements are removed and reused in the reactor leaving the waste "purified" of those heavy elements. So the really dangerous stuff never leaves the building and is used up to produce energy. This means instead of having waste that is dangerous for tens of thousands of years you only have to worry about it for a few hundred. But I guess the some of the output from a IFT then could be used in something like a CANDU reactor? So you could use the combination of the two to use up most of the fissionable material and until the waste is so depleted that it is useless and is turned into ceramics or glass and safely stored. Something like that. Regardless this means that nuclear reactors provide the closest we can possibly get to truly renewable energy source and provide a path forward away from fossil fuels that could meet the energy budget of the planet for the next hundred thousand years or so. Anybody who really cares even a little bit about the environment and global warming should be clamoring loudly for this sort of tech. Large scale nuclear power production combined with locally produce small scale (I mean distributed) solar makes a lot of sense, IMO.
- arcticbull 4y ago
  U238 isn't used in current designs because there's so much U235, and the input cost of using U235 is low enough relative to the value of the electricity generated that it's not worth using the U238 - generally speaking. It however can be used in fast neutron reactors or breeder reactors. [1] [1] https://energyeducation.ca/encyclopedia/Breeder_reactor https://energyeducation.ca/encyclopedia/Breeder_reactor
  - Retric 4y ago
    Your general point is correct, however both U238 and U235 are are consumed by commercial reactors right now. U238 > U239 decay into neptunium-239 which then decays into Plutonium-239. Essentially there is so much U238 in the reactor and so many neutrons flying around the above just happens.
    - arcticbull 4y ago

Retric 4y ago

That’s basically abusing the word uranium as U235 is used up while U238 is largely not in current designs. Reprocess spent fuel lets you extract the leftover U235, but it’s a small percentage of the original amount. What you want is something like the CANDU design which is far less dependent on U235. https://en.wikipedia.org/wiki/CANDU_reactor https://en.wikipedia.org/wiki/CANDU_reactor

lazyier 4y ago
Yeah. I am no expert by any means. I was thinking of something more along the lines of an integral fast reactor were the heavy elements are removed and reused in the reactor leaving the waste "purified" of those heavy elements. So the really dangerous stuff never leaves the building and is used up to produce energy. This means instead of having waste that is dangerous for tens of thousands of years you only have to worry about it for a few hundred. But I guess the some of the output from a IFT then could be used in something like a CANDU reactor? So you could use the combination of the two to use up most of the fissionable material and until the waste is so depleted that it is useless and is turned into ceramics or glass and safely stored. Something like that. Regardless this means that nuclear reactors provide the closest we can possibly get to truly renewable energy source and provide a path forward away from fossil fuels that could meet the energy budget of the planet for the next hundred thousand years or so. Anybody who really cares even a little bit about the environment and global warming should be clamoring loudly for this sort of tech. Large scale nuclear power production combined with locally produce small scale (I mean distributed) solar makes a lot of sense, IMO.
arcticbull 4y ago
U238 isn't used in current designs because there's so much U235, and the input cost of using U235 is low enough relative to the value of the electricity generated that it's not worth using the U238 - generally speaking. It however can be used in fast neutron reactors or breeder reactors. [1] [1] https://energyeducation.ca/encyclopedia/Breeder_reactor https://energyeducation.ca/encyclopedia/Breeder_reactor
- Retric 4y ago
  Your general point is correct, however both U238 and U235 are are consumed by commercial reactors right now. U238 > U239 decay into neptunium-239 which then decays into Plutonium-239. Essentially there is so much U238 in the reactor and so many neutrons flying around the above just happens.
  - arcticbull 4y ago