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Solar energy now overlaps in cost with nuclear fuel alone for "cheap" modular reactors
(energy-utilities.com)
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this post was submitted on 26 Aug 2023
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Okay, some basic physics here, to make thorium useful, you have to convert it to uranium (specifically uranium-234)
That's how a molten salt reactor functions, they use a seed of fissile material to breed the thorium into protactinium, which then decays into uranium.
Once you have the u-234, you can use it to breed the thorium, but you do need that seed of either u-235 or plutonium.
As for u-235 and u-238, well, those are full of harvestable energy as well. U-235 is what we burn in reactors because u-238 is fertile, not fissile. U-238 breeds up to p-239, which can explode if you know what you're doing, but can also be burned in a reactor for massive amounts of power.
We have the technology to do all of this right now. It's not 10-20 years out, it's today. What we don't have is an easy way to overcome decades of oil company anti-nuclear propaganda.
No breeder program has ever worked. The best was a couple of low burnup proofs of concept of breeding. They all failed trying to do proof of concept for the reprocessing step -- usually after many billions in subsidies.
Running a full fuel load of the steady-state isotope mix hasn't even been attempted.
https://en.m.wikipedia.org/wiki/Superph%C3%A9nix
Super Phoenix was a prototype super breeder reactor built in France. It has issues in the first years (normal for a prototype) but by the end it was running with an availability of 96%.
Like every other program, if it never made more fissile material than was loaded with, and then ran on that material, it's just a U235 reactor that caught fire more often
Correct me if I'm wrong but I don't think superphenix used any U235. The fuel is Pu239 and U238.
So I don't understand your claim since no U235 was used in this reactor.
Edit: The reactor in talking about never caught fire. Your whole message is false information
For anyone still reading, Phenix's fuel cycle (superphenix never really did anything at all except break down but it's basically the same, just a little bit higher burnup so slightly more Pu and energy at the last step).
Mine 3000t of uranium ore from Nigeria. Leave 2999t of very low level radioactive heavy-metal laden rock and sulfuric acid slurry behind in a poorly built dam for the people of Arlit to deal with.
Separate 130kg of ~4% enriched U with 5kg of U235. Leave 870kg of depleted but highly toxic and corrosive UF6 in a barrel for your grandkids to deal with.
Put the 130kg of fuel in a LWR. Get ~100TJ (140TJ in a gen iii reactor nowadays).
Separate the 1kg of Pu remaining, dump most of the Cs, Tc99 and a few other fission products into the north sea (which is still detectable in safe, but high levels in fish in Norway). This bit costs more than mining the fuel did. Radiate your own people a little with Xe-85.
"Save" the 123kg of Uranium with 1.2kg of fissile isotopes in a "strategic reserve". Nobody with a centrifuge anywhere outside of Mayak will ever enrich this because it is highly contaminated with U234, U236 and U232. It's waste. You could pretend it had 20TJ in it if you were a nukebro.
Put the 1kg of Pu in Phenix. Fission 20g of it. Get 200GJ.
Now you have 20g of super-weapons grade plutonium and 980g of plutonium that is too full of Pu240, Pu241, Pu242, Am and a few other elements to use. It's waste, nobody will ever enrich it.
Congratulations! You did a closed-loop fuel cycle! Energy solved! You have 200GJ worth of fissile material and 0.1% more energy than just using an LWR! If you did it again you could get 0.101% extra energy!
Now let's go spend the same amount as $85/W PV for the same energy output costs in 1976 on superphenix!
The Pu came from either a graphite pile or an LWR like all other Pu and wasn't involved in any process that made more than was inserted and turned into waste. MOX with extra steps and no closed cycle is still just MOX.
Also it shut down in 1992 because of air in the molten hot sodium. What do you call hot oxidising sodium?
So far we've got:
Combining oxygen with sodium isn't fire.
Running for a total of 6 months in ten years is 96% availability.
Net consumption of fissile material with no attempt at reprocessing into fuel for another cycle is breeding.
Net importing electricity from germany (and importing every month except for spring and autumn where local wind and solar is most abundant) is exporting "large amounts".
Do you even understand how ridiculous you sound? Like is this a self-humiliation thing?
Also you're lying about the second part https://pris.iaea.org/PRIS/CountryStatistics/ReactorDetails.aspx?current=178
You see, the rule of thumb is very easy. If a nukebro or industry PR tells you something, there's a 96% chance it's a lie until someone else checked and they backpedalled at least 5 times. This is in spite of being forced to report the truth through other channels much of the time.
It's U233
So it is... That's what I get for typing that completely by memory.
U-234 is the side product... It's another fertile form of uranium that can form when you don't get the protactinium out fast enough...
You also get U232 and a bunch of other actinides. Then you have to turn your reactor off because the void coefficient and delayed neutron fraction keep changing and you don't want it to go prompt critical.
Then you have a bunch of gamma emitting salt there's no clean or affordable chemical process for separating, and you leave it lying around for 50 years before finally burying it at huge expense.
You did get the benefit of pointing to your failed experiment every time someone points out that LWRs are unsustainable though, so that's nice.
Maybe BN-800 will finally be run in breeding mode but not as an obvious shell game to make weapons grade plutonium now that it's more than a year old and catching fire as often as every other sodium cooled reactor?