Economics of Plutonium/Isotope Producing Breeder Reactors?

Delta Force

Banned
Although currently not economically competitive with other means of producing nuclear fuel and power, could a breeder reactor produce plutonium and other isotopes at a lower cost than other nuclear technologies? Is there a way to determine how much plutonium and other isotopes a breeder reactor of a given output and breeding ratio can produce, similar to the rules of thumb for conventional light water, heavy water, and gas cooled graphite moderated reactors (1 gram plutonium per MWht for natural uranium designs, 0.5 grams of plutonium MWht for enriched uranium designs)?

For the purposes of this discussion plutonium is the main isotope of interest, as it is a material that is produced and used in large quantities for military and other primarily governmental applications where a niche solution could be considered, especially since governments were already funding breeder reactor programs (and in countries with them) plutonium and isotope production programs.
 

Perkeo

Banned
Although currently not economically competitive with other means of producing nuclear fuel and power, could a breeder reactor produce plutonium and other isotopes at a lower cost than other nuclear technologies?

Is there a technology to produce significant quantities of plutonium other than breeding in a reactor? Is there really a large differnce between a reactor that is designed to breed isotopes and a breeder reactor. IMO the latter is no more and no less than a good implementation of the former. [to clear terminology: according to Wikipedia, a breeder reactor is a nuclear reactor that generates more fissile material than it consumes.]

Is there a way to determine how much plutonium and other isotopes a breeder reactor of a given output and breeding ratio can produce, similar to the rules of thumb for conventional light water, heavy water, and gas cooled graphite moderated reactors (1 gram plutonium per MWht for natural uranium designs, 0.5 grams of plutonium MWht for enriched uranium designs)?

For the purposes of this discussion plutonium is the main isotope of interest, as it is a material that is produced and used in large quantities for military and other primarily governmental applications where a niche solution could be considered, especially since governments were already funding breeder reactor programs (and in countries with them) plutonium and isotope production programs.

The fuel efficiency of breeder reactors isn't a cost factor since fuel isn't a cost factor. Safety is, and a safe breeder reactor is a lot more expensive than a safe lightwater reactor.

Nuclear waste would make the breeder reactor more attractive, but that requires a less bipolar culture of debate than IOTL.
 
Bumpity bump.
you know how ursus californicus thinks about that

Is there a technology to produce significant quantities of plutonium other than breeding in a reactor? Is there really a large differnce between a reactor that is designed to breed isotopes (1) and a breeder reactor(2). IMO the latter is no more and no less than a good implementation of the former. [to clear terminology: according to Wikipedia, a breeder reactor is a nuclear reactor that generates more fissile material than it consumes.]

i think that 1 is a reactor that exists for the pure reason of creating isotopes, not just Pu isotopes, so more a reactor that produces medical & commercial isotopes, 2 is a reactor that is producing the same fissile material that it consumes
 

Perkeo

Banned
i think that 1 is a reactor that exists for the pure reason of creating isotopes, not just Pu isotopes, so more a reactor that produces medical & commercial isotopes, 2 is a reactor that is producing the same fissile material that it consumes

No, 2 would be a perpetuum mobile.

OK, EVERY reactor that produces Plutonium is more or less based on the following reaction:

n + 238U -> 239Pu

The only difference is that a breeder reactor can use the neutrons from the fission so efficiently that more non-fissile nuclei become fissile
than fissile nuclei are destroyed to produce those neutrons.

Therefore, the difference between a good isotope-producing reactor and a breeder reactor is somewhat evolutionary.
 
yes, i know, that

also i could imagine a breeder reactor that is optimised for producing fuel, instead of hybrid energy/fuel production.
It might have benefits with regards to construction and maintenance
 
One of the major problems of a plutonium breeder is you then have to separate the Pu out of the highly radioactive spent fuel. THEN you have to transport it to wherever your fuel fabrication facility is, under massive safeguards so that terrorists can't steal it. For instance.

Also, you'd not want to sell those reactors abroad (Nonproliferation), and most countries want to sell their designs abroad for economies of scale.

In many ways, something like a Candu which has a massive burn up ratio is a better option. (Candus can even be tweaked to be slow breeders.)

Also. It's much, much easier to build a slow breeder than a fast breeder, but if it takes the life of your plant to generate as much Pu as you put in U, that's not going to be economic in any scenario, surely.

Now. The proliferation problem goes away if you use Thorium reactors, as the U233 (iirc) fissile isotope is radioactive enough that few would try removing it for bombs. However, transport, processing, radioactivity of fuel rods, all those are still problems.
 

Delta Force

Banned
Is there a technology to produce significant quantities of plutonium other than breeding in a reactor?

Particle accelerators have been proposed for plutonium breeding.

Is there really a large differnce between a reactor that is designed to breed isotopes and a breeder reactor. IMO the latter is no more and no less than a good implementation of the former. [to clear terminology: according to Wikipedia, a breeder reactor is a nuclear reactor that generates more fissile material than it consumes.]

Non-breeder reactors used to breed isotopes are usually called plutonium/isotope production reactors, depending on what their primary purpose is. Breeder reactors produce more fissile material than they consume, while non-breeder reactors do not.

The fuel efficiency of breeder reactors isn't a cost factor since fuel isn't a cost factor. Safety is, and a safe breeder reactor is a lot more expensive than a safe lightwater reactor.

Nuclear waste would make the breeder reactor more attractive, but that requires a less bipolar culture of debate than IOTL.

The primary question for this though is if a breeder reactor could produce plutonium and other isotopes at a lower cost than conventional non-breeder production reactors. If the reactors are only used for materials production then the costs and complexity of adding electricity generating equipment aren't required, and it might be possible to design/operate the reactor to further optimize isotope production without the competing priority of power production.
 

Delta Force

Banned
yes, i know, that

also i could imagine a breeder reactor that is optimised for producing fuel, instead of hybrid energy/fuel production.
It might have benefits with regards to construction and maintenance

The reactors would be less expensive and likely more reliable without the need to generate electricity. Most of the reliability issues with liquid metal fast breeder reactors are due to fires breaking out in the secondary coolant loop used to produce electricity (the primary coolant loop cools the reactor itself).
 

Delta Force

Banned
One of the major problems of a plutonium breeder is you then have to separate the Pu out of the highly radioactive spent fuel. THEN you have to transport it to wherever your fuel fabrication facility is, under massive safeguards so that terrorists can't steal it. For instance.

Also, you'd not want to sell those reactors abroad (Nonproliferation), and most countries want to sell their designs abroad for economies of scale.

In many ways, something like a Candu which has a massive burn up ratio is a better option. (Candus can even be tweaked to be slow breeders.)

Also. It's much, much easier to build a slow breeder than a fast breeder, but if it takes the life of your plant to generate as much Pu as you put in U, that's not going to be economic in any scenario, surely.

Now. The proliferation problem goes away if you use Thorium reactors, as the U233 (iirc) fissile isotope is radioactive enough that few would try removing it for bombs. However, transport, processing, radioactivity of fuel rods, all those are still problems.

That's true, but it's also an issue that exists for conventional reactors used to produce plutonium and other isotopes. The primary purpose for a plutonium producing reactor would be military and other governmental applications anyways.
 
Although currently not economically competitive with other means of producing nuclear fuel and power, could a breeder reactor produce plutonium and other isotopes at a lower cost than other nuclear technologies?

I would expect that a breeder reactor, once built, would produce plutonium and other isotopes at a lower cost per kg than production piles or accelerators. But, unless you need just gob-smacking amounts of plutonium, the price of developing the breeder reactor would almost certainly be far greater than the cost saving from the lower production cost. Plus, all of the breeder designs I'm aware of produce plutonium heavily contaminated with Pu-240, which makes them highly suboptimal for weapons use.

As for amounts, if you find a design you like and dig up the R&D documents, they'll usually list the fuel inventory and the doubling time. That will give you the production rate.
 

Delta Force

Banned
I would expect that a breeder reactor, once built, would probably produce plutonium and other isotopes at a lower cost per kg than production piles or accelerators. But, unless you need just gob-smacking amounts of plutonium, the price of developing the breeder reactor would almost certainly be far greater than the cost saving from the lower production cost.

Billions of dollars were spent developing civilian breeder reactors suitable for power production, so isotope producing reactors might be possible with the same or a slightly increased budget since they wouldn't need any power generation equipment. Most of the issues with liquid metal fast breeder reactors are due to the secondary coolant loop and turbine assembly, so omitting those two features could allow for a practical production reactor design. Given the excellent primary cooling characteristics demonstrated by EBR-II, the design could even be safer than conventional pile reactors.

Plus, all of the breeder designs I'm aware of produce plutonium heavily contaminated with Pu-240, which makes them highly suboptimal for weapons use.

Conventional nuclear reactors have issues with plutonium-240 contamination too, although the issue can be mitigated through frequent fuel changes. How much of the contamination in breeder reactors is due to design vs. fuel cycle?

As for amounts, if you find a design you like and dig up the R&D documents, they'll usually list the fuel inventory and the doubling time. That will give you the production rate.

Where have you been able to find this information? Have you found anything on fuel and coolant inventories for other types of reactors?
 
Billions of dollars were spent developing civilian breeder reactors suitable for power production, so isotope producing reactors might be possible with the same or a slightly increased budget since they wouldn't need any power generation equipment.

By the time you finish that development, you'll have already finished building the Hanford complex or something like it, which historically was sufficient to produce all the plutonium the US needed for tens of thousands of nuclear bombs.

Most of the issues with liquid metal fast breeder reactors are due to the secondary coolant loop and turbine assembly, so omitting those two features could allow for a practical production reactor design. Given the excellent primary cooling characteristics demonstrated by EBR-II, the design could even be safer than conventional pile reactors.

This non-power-producing LMFBR is still going to need a secondary coolant loop dumping waste heat into a lake or river. You can run it at a lower temperature than a power producer, which helps, but it's still going to have the potential for sodium-water fires if the secondary loop leaks.

Conventional nuclear reactors have issues with plutonium-240 contamination too, although the issue can be mitigated through frequent fuel changes. How much of the contamination in breeder reactors is due to design vs. fuel cycle?

I'm not entirely sure, but my gut instinct is that you'll lose a lot of the advantages of a breeder with a change in the fuel cycle. The breeder pumps out huge amounts of neutrons, that's what makes it a breeder, so it can turn lots of U-238 into Pu-239, and lots of Pu-239 into Pu-240, really quickly. So you'll probably be shutting it down very frequently to change fuel loadings. Since what you're concerned with is plutonium production averaged over time, and it's not making any fuel while it's shut down, I suspect its average production will be a lot lower than its raw numbers would suggest.

In theory, you can make a breeder that can change fuel without shutting down, like the CANDU or the liquid-fuel reactors. Heck, you can make a liquid fuel breeder if you want to (LAMPRE for the win!). Aside from LAMPRE and its descendants, though, I can't recall seeing an LMFBR that can refuel without shutdown, which makes me wonder if there's some technical reason I'm not aware of that you don't want to do that in an LMFBR.

Where have you been able to find this information? Have you found anything on fuel and coolant inventories for other types of reactors?

SciTech Connect - if you search the database for the name of a US reactor design, you'll usually get a ton of documents. And yes, I've found information on fuel and coolant inventories for a wide variety of US experimental and production reactors.
 

Delta Force

Banned
By the time you finish that development, you'll have already finished building the Hanford complex or something like it, which historically was sufficient to produce all the plutonium the US needed for tens of thousands of nuclear bombs.

Weren't those facilities being considered for replacement by the 1980s?

This non-power-producing LMFBR is still going to need a secondary coolant loop dumping waste heat into a lake or river. You can run it at a lower temperature than a power producer, which helps, but it's still going to have the potential for sodium-water fires if the secondary loop leaks.

A lot of fires start in the turbine itself due to the nature of those systems, so the secondary loop would probably still be significantly more reliable.

I'm not entirely sure, but my gut instinct is that you'll lose a lot of the advantages of a breeder with a change in the fuel cycle. The breeder pumps out huge amounts of neutrons, that's what makes it a breeder, so it can turn lots of U-238 into Pu-239, and lots of Pu-239 into Pu-240, really quickly. So you'll probably be shutting it down very frequently to change fuel loadings. Since what you're concerned with is plutonium production averaged over time, and it's not making any fuel while it's shut down, I suspect its average production will be a lot lower than its raw numbers would suggest.

In theory, you can make a breeder that can change fuel without shutting down, like the CANDU or the liquid-fuel reactors. Heck, you can make a liquid fuel breeder if you want to (LAMPRE for the win!). Aside from LAMPRE and its descendants, though, I can't recall seeing an LMFBR that can refuel without shutdown, which makes me wonder if there's some technical reason I'm not aware of that you don't want to do that in an LMFBR.

Don't sodium cooled reactors operate at atmospheric pressure? Have any of them used online refueling? Clinch River had an "in-vessel transfer machine" for use during refueling that was derived from the West German SNR-300, and apparently EBR-II and the Fast Flux Test Facility had similar systems.

CRBRinvesselrefuelingmech.jpg


CRBRreactorhead.jpg


SciTech Connect - if you search the database for the name of a US reactor design, you'll usually get a ton of documents. And yes, I've found information on fuel and coolant inventories for a wide variety of US experimental and production reactors.

Is there anything for foreign designs?
 
Weren't those facilities being considered for replacement by the 1980s?

Probably, though I'm not familiar with the specific plans. But by that point we had so much plutonium lying around that we didn't really need any more.

Don't sodium cooled reactors operate at atmospheric pressure? Have any of them used online refueling? Clinch River had an "in-vessel transfer machine" for use during refueling that was derived from the West German SNR-300, and apparently EBR-II and the Fast Flux Test Facility had similar systems.

They do operate at atmospheric pressure, yeah. I don't know of any reason why you couldn't do online refueling, but aside from the liquid-fuel designs, I don't know of any that were planned to do so, which makes me wonder if there's some reason why you can't that I'm not aware of.

Is there anything for foreign designs?

Some stuff, but not as much.
 

Delta Force

Banned
They do operate at atmospheric pressure, yeah. I don't know of any reason why you couldn't do online refueling, but aside from the liquid-fuel designs, I don't know of any that were planned to do so, which makes me wonder if there's some reason why you can't that I'm not aware of.

If the reactor is being used for civilian purposes then there isn't really a need to limit plutonium-240 production. It's a breeder reactor, so it doesn't really to take on more fuel during operations, and the fuel can be changed out during the maintenance cycles when all the sodium has to be drained out anyways.

There might also be issues with plutonium being highly flammable. A fire in the secondary coolant loop or turbine room is quite different from a fire in/near the reactor vessel.
 
If the reactor is being used for civilian purposes then there isn't really a need to limit plutonium-240 production. It's a breeder reactor, so it doesn't really to take on more fuel during operations, and the fuel can be changed out during the maintenance cycles when all the sodium has to be drained out anyways.

Most breeders - especially the older designs - do have to be regularly refueled. While the total amount of fissiles in the core is (more or less) constant, there's a limit on how long the fuel rods can hold up; they need to be periodically removed, reprocessed, and recast, or else they eventually fail, releasing nastiness into the coolant stream. Also, most designs, old and new, use separate breeding blankets, so the new plutonium is being generated outside the core. If you could do online refueling, you could limit your downtime to what you need for maintenance only, which would be a nice feature.

These days, it seems like materials are getting to the point where we can at least talk about fuel rods tough enough to never need to be replaced until they're completely used up, as in the Traveling/Standing Wave Reactor. It's not clear to me if this is actually practically doable right now, but it's at least something that we might be doable in the not-too-distant future. But that's what you get from fifty years of R&D, it's not something we could do back in the '60s.

There might also be issues with plutonium being highly flammable. A fire in the secondary coolant loop or turbine room is quite different from a fire in/near the reactor vessel.

Historically, most LMFBR designs used plutonium oxide ceramic, which is nasty stuff but not flammable. Though I still wouldn't want a sodium fire anywhere near it.
 

Delta Force

Banned
Most breeders - especially the older designs - do have to be regularly refueled. While the total amount of fissiles in the core is (more or less) constant, there's a limit on how long the fuel rods can hold up; they need to be periodically removed, reprocessed, and recast, or else they eventually fail, releasing nastiness into the coolant stream. Also, most designs, old and new, use separate breeding blankets, so the new plutonium is being generated outside the core. If you could do online refueling, you could limit your downtime to what you need for maintenance only, which would be a nice feature.

These days, it seems like materials are getting to the point where we can at least talk about fuel rods tough enough to never need to be replaced until they're completely used up, as in the Traveling/Standing Wave Reactor. It's not clear to me if this is actually practically doable right now, but it's at least something that we might be doable in the not-too-distant future. But that's what you get from fifty years of R&D, it's not something we could do back in the '60s.

Historically, most LMFBR designs used plutonium oxide ceramic, which is nasty stuff but not flammable. Though I still wouldn't want a sodium fire anywhere near it.

I meant sodium, not plutonium, but both can catch fire. The mechanism would have to be fireproofed somehow.
 
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