5 ms·

Objectively speaking, the smallest reactor would require at least a few tens of kg of fissile material, due to the physics involved. So due to the proliferation

Objectively speaking, the smallest reactor would require at least a few tens of kg of fissile material, due to the physics involved. So due to the proliferation and terrorism risks, even the smallest district nuclear would still need to be a large industrial facility with heavy security, owned by a powerful entity that can foot the insurance and legal costs etc. So it's not something any amateur tinkerer would touch any time soon.

surfingdino 2y ago
What happens when the manufacturer of the reactors goes bust? Will the government take over monitoring and maintenance?
- fnordian_slip 2y ago
  Good point. They'd have to, and this would mean the energy companies model of "privatise the profits, socialise the losses" might go into hyperdrive. On the other hand, nuclear energy is heavily subsidised already anyway, and its proponents seem to be very good at ignoring that, so maybe this does not matter to most.
Propelloni 2y ago
> owned by a powerful entity that can foot the insurance and legal costs etc. This is not the case with current "large" reactors, why would it be different here? Those risks you mention are mutualized because no single entity but a state could bear them.
- krisoft 2y ago
  It is absolutely the case with the current "large" reactors. They are owned by huge companies not by the next door dude. This is what the commenter said. It would be the same even for "microreactors". > Those risks you mention are mutualized because no single entity but a state could bear them. You are talking about something else. You are saying they are not big enough to cover all possible liability. That is not what cornholio is saying.
  - Propelloni 2y ago
    I see what you are getting at and I agree, I could have phrased that better. So here is what I meant to ask: the capacity to cover liability apparently has no bearing on ownership of today's large reactors, so why would it be different with smaller reactors?
preisschild 2y ago
It is possible to use proliferation-hardened fuel, like TRISO, that can't easily be separated again.
- adrianN 2y ago
  You can still use it nicely for terrorism.
- cornholio 2y ago
  From what I understand, TRISO is more about reactor safety than proliferation. A proliferating entity could easily ground up the particles and chemically leech the useful fissile material, they need to do enrichment anyway which is orders of magnitude more difficult. A good anti-proliferation design are traveling wave U238 fast breeders. They are filled with depleted uranium and breed plutonium 239, but, due to the long residence time in the reactor, the isotopic vector is heavily polluted with things like Pu240 which spontaneous fissions reducing the yield, Pu238 which generates massive heat etc. This reactor grade plutonium is completely worthless as a bomb material and would require reprocessing that is even more difficult then enrichment of natural Uranium. Alas, none of the TWR proposals (CANDLE, Terrapower etc.) ever made it into production.

surfingdino 2y ago

What happens when the manufacturer of the reactors goes bust? Will the government take over monitoring and maintenance?

fnordian_slip 2y ago
Good point. They'd have to, and this would mean the energy companies model of "privatise the profits, socialise the losses" might go into hyperdrive. On the other hand, nuclear energy is heavily subsidised already anyway, and its proponents seem to be very good at ignoring that, so maybe this does not matter to most.

Propelloni 2y ago

> owned by a powerful entity that can foot the insurance and legal costs etc. This is not the case with current "large" reactors, why would it be different here? Those risks you mention are mutualized because no single entity but a state could bear them.

krisoft 2y ago
It is absolutely the case with the current "large" reactors. They are owned by huge companies not by the next door dude. This is what the commenter said. It would be the same even for "microreactors". > Those risks you mention are mutualized because no single entity but a state could bear them. You are talking about something else. You are saying they are not big enough to cover all possible liability. That is not what cornholio is saying.
- Propelloni 2y ago
  I see what you are getting at and I agree, I could have phrased that better. So here is what I meant to ask: the capacity to cover liability apparently has no bearing on ownership of today's large reactors, so why would it be different with smaller reactors?

preisschild 2y ago

It is possible to use proliferation-hardened fuel, like TRISO, that can't easily be separated again.

adrianN 2y ago
You can still use it nicely for terrorism.
cornholio 2y ago
From what I understand, TRISO is more about reactor safety than proliferation. A proliferating entity could easily ground up the particles and chemically leech the useful fissile material, they need to do enrichment anyway which is orders of magnitude more difficult. A good anti-proliferation design are traveling wave U238 fast breeders. They are filled with depleted uranium and breed plutonium 239, but, due to the long residence time in the reactor, the isotopic vector is heavily polluted with things like Pu240 which spontaneous fissions reducing the yield, Pu238 which generates massive heat etc. This reactor grade plutonium is completely worthless as a bomb material and would require reprocessing that is even more difficult then enrichment of natural Uranium. Alas, none of the TWR proposals (CANDLE, Terrapower etc.) ever made it into production.