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Solar energy now overlaps in cost with nuclear fuel alone for "cheap" modular reactors
(energy-utilities.com)
this post was submitted on 26 Aug 2023
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And are we taking into account safe storage of nuclear waste for thousands of years (which we as civilization still don't even have) or not?
Today's journalists are really superficial.
That's what blew me away. People keep saying a lot of hand wavy stuff about storage but when you really dig into there isn't a great solution other than keeping an eye on it for a few hundred years. Making private company's responsible for stuff that generates no profits and requires repeated Inspection's and maintenance doesn't sound good to me.
We absolutely need nuclear. But we should approach it cautiously. I don't think discussion about nuclear is as cautious as it should be. But that's par for the course with humanities track record
There's no need to consider nuclear. The power storage requirements for a 100% - epsilon renewable grid are vastly smaller than the amount of battery that will be deployed to EVs in the next few years.
https://www.nature.com/articles/s41467-021-26355-z
Those batteries can be used either after they degrade to the point where the EV needs a new one, or while still in the EV if a small fraction of owners participate in V2G.
Additionally the accessible uranium reserves cannot make a significant impact on the world's energy requirements.
In 8 million tonnes of accessible natural uranium there are about 56,000 tonnes of U235. Fissioning all of this yields around 5000EJ of thermal energy Exhausting all techniques of reprocessing and breeding that have actually ever worked, there's about 10,000EJ.
The world used 620EJ of primary energy last year so the absolute most generous interpretation is there are 16 years of accessible fission energy, In any realistic scenario it's much, much less.
The amount of energy that can be provided via fission with current technology isn't a meaningful contribution and can't be deployed in a meaningful timeframe.
There may be niches where GW scale LWRs are a much better choice than other options. On the off chance they do crop up, what little uranium 235 there is should be reserved for those.
It still sounds crazy to most people : it's a long way to go that should be paved for speeding up modern consciousness.
Fun fact, That "thousands of years" of storage is entirely a man made limitation.
95% of nuclear waste is unspent fuel. That's the source of the "thousands of years" waiting for the more energetic parts of the unspent fuel to decay.
There are a couple of nasty decay side products that last a long time in there, but those can also be fed into a reactor to be burned away. That's about 1% of waste. (mostly plutonium)
Pretty much everything else, the remaining ~4% or so of waste, is only really super dangerous for about 60-90 years, and only radioactive for about 300.
Another fun fact, a lot of that 4% is actually valuable in various industry, including nuclear medicine.
I always point to this video on the subject.
Sadly, Jimmy Carter signed a ban on refining waste, and then got it incorporated into some international agreements. He thought we would just bury the waste again, it came out of the Earth, it could go back in until we were ready to refine it and move on. Sadly, Nymbyism killed that plan.
Are we talking about present or future?
Nuclear has a chance in thorium and malten salt reactors, uranium is made for nuclear booms, not for safe energy generation.
Sadly, no one is investing enough in thorium and malten salt to make it available in next 10-20 years, we have better chance in fusion than thorium.
Until than, sorry, but while you are right, that technology is not yet available.
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.
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?
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%.
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.
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?
This is a myth. Fissile isn't fertile. No breeding program has ever worked and none even aspire to burn all the actinides.
You're also pretending the only waste product is spent fuel.
95% of waste is un-burnt uranium. That's the full truth.
The 1% of waste that's plutonium is the full reason we don't allow reprocessing or breeding programs. Even though there's no evidence of any country using their civilian nuclear power program to create weapons.
No, they use their military nuclear programs to do that.
If you watch the video, it covers all of it. Every side product, every decay product, and it walks it through several thousand years of decay.
You're still trying to conflate U238 which isn't a fissile element with nuclear fuel. This is a lie. It's like saying plastic waste is un-fusioned carbon and hydrogen and is actually nuclear fuel. By the most tortured definition it is true, but you have not communicated anything. Instead you are intentionally misleading.
You're also trying to pretend U238 and Pu239 are where the danger is. Pu240, Am and fission products are the radioactive part. Extracting the Pu239 doesn't change the dangerous radioactivity meaningfully.
You've also doubled down on pretending spent fuel is the only waste product. 95% of the waste by volume is not high level waste and most of the high level waste is not spent fuel.
This propaganda technique and method of lying is called paltering.
U-238 is fuel, you just need to run a reactor type that was mostly banned in the 70s. Otherwise u-238 is not a big deal to handle. If you don't want to burn it, just bury it where you found it, or convert it to the oxide and mix it with a few thousand gallons of water before dumping it out at sea. (which is where 99% of uranium can be found)
And yeah, plutonium is the dangerous stuff, but it's also the best fuel you can get. Sure, Pu-240 is an issue, but it's also solvable. And by solvable, I mean that it's one more neutron away from being fuel again. This does slow the reaction, after all, it takes multiple neutrons to become fissile again. Pu-241 is back to being fuel. Pu-242 is not fuel, but also has a low cross-section.
That video I linked talks about all of this. It runs through a typical burn of a light water reactor, and breaks down what percentage of everything is in the waste, from day one out to several hundred thousand years. It also gives a dollar amount for each part on the open market.
Even so, if you really don't want the transuranics, just use the thorium cycle. There are a dozen reactor designs that can handle thorium. We just need to let people build them.
Working breeder programs are a myth and condescendingly telling me to watch a video taking a narrow myopic view of things I already know (which ignores all the important points) isn't helping your point.
Show me where I can find documentation of a reactor running on U238 or Th which actually worked for a complete fuel cycle and wasn't just the same breeding ratio as a U235 but with extra steps.
You've also not addressed the hard bit either, which happens outside the reactor.
Also nobody banned breeders, breeder programs are still eating huge amounts of public money and failing to do anything useful in india and china to this day. Superphenix and Monju also weren't banned in the 70s. Nor were the BN reactors.
The only reason they exist is for plausible deniability on filthy loss-making Pu separation equipment for weapons, and for people like you to palter with.
Reprocessing fuel for breeder reactors was the thing that was banned. Now there have to be all sorts of workarounds that don't work well.
...banned in a couple of countries for four years.
Why is every single one of these always a trivially verifiable lie?
Oh you're a lftr bro.
Do you realise how hilarious it is that your proposed solution to mineral scarcity and toxicity of the product lifecycle is 2kg of beryllium per capita?
I said,
But every reply I've gotten from you has been you not actually addressing what I've said, but you, instead, seem to be replying to what you wish I'd said. There's some disconnect.
Ah so now it's one of those superposition reactors which has the all the upsides all the different people trying to sell them imagined after building half of one and having it fall apart in a year, but none of the downsides. Also a U235 reactor running Th in place of U238 for a breeding ratio of 0.5 somehow means U235 ia sn't needed anymore.
The disconnect is you are pretending a half-proof-of-concept of the easiest bit is all the hard bits being complete.
This is just the marginal cost of the front end of the cycle ignoring the back end and all other fixed or marginal costs.
Ie. If you already have bought an SMR in a high-solar-resource region, is it cheaper to buy fuel to run it during the day or to buy solar panels instead and turn it off. The answer being it's a wash right now, but uranium is going up for the moment and solar is going down for now.
Safe storage of nuclear waste hasn’t been an issue for decades. You see it comes from this place called the ground, and goes back into this place called the ground. I know, it’s like science fiction.