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this post was submitted on 01 Aug 2023
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Oh, neat. My state did something not completely stupid. I've got some reservations about nuke power as opposed to renewable, but this is definitely better than continuing fossil fuels.
Fission and fusion reactors are really more like in-between renewable and non-renewable. Sure, it relies on materials that are finite, but there is way, way more of that material available in comparison to how much we need.
Making this distinction is necessary to un-spook people who have gone along with the panic induced by bad media and lazy engineering of the past.
Fusion and fission are quite different. A practical fusion reactor does not exist. It's outside our technological capability right now. Current fusion reactors are only experimental and can not maintain a reaction more than a small fraction of a second. The problem is plasma containment. If that can be solved, it would be possible to build a practical fusion reactor.
The fuel for a working fusion reactor would likely be deuterium/tritium which is in effect unlimited since it can be extracted from seawater. Also the amount of fuel required is small because of the enormous amounts of energy produced in converting mass to energy. Fusion converts about 1% of mass to energy. Output would be that converted mass times the speed of light squared which is a very, very large number, in the neighborhood of consumed fuel mass times 10^15^.
Fusion is far less toxic to to the environment. With deuterium/tritium fusion the waste product is helium. All of the particle radiation comes from neutrons which only require shielding. Once the kinetic energy of the particles is absorbed, it's gone. There's no fissile waste that lingers for some half life.
Wow. Thanks for breaking this down in layman’s terms, super interesting.
Here's something more interesting. A matter-antimatter reactor converts 100% of mass to energy so it's a hundred times more efficient than fusion. In modern times antimatter has been produced at quantum levels in large accelerators such as the Hadrian collider. So it does in fact exist and can be produced.
However a matter-antimatter reactor has some serious technical problems. For one it's currently impossible to create antimatter in any practical quantity. Second if antimatter comes in contact with matter, instant boom. Like a sugar cube size of the stuff could level a large city. So containment would be an insurmountable problem.
The interesting part is when you see an antimatter reactor in shows like Star Trek, it's based on real science. Interestingly in 1968 when they wrote the original Star Trek, nobody knew antimatter was a physically real thing. That's a case of sci-fi predicting science.
The internet can be cool sometimes.
But antimatter needs energy to create, probably more energy than it can produce. Unless you can find some source of it in the environment. Fusion is much more likely to be feasible.
Antimatter might make a good compact way to store energy for a starship, if it was created in a large fixed facility with access to huge power sources. But it's not a way to generate energy by itself.
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LWR fuel is incredibly limited without a massive fleet of breeders (and no breeder has ever run a full fuel cycle, nor has second generation MOX ever been used. First generation MOX is also incredibly polluting and expensive to produce).
The industry is already on to tapping uranium ore sources that are less energy dense than coal, and this is to provide a few % of world energy for a handful of decades.
redacted
I'm spooked by the fact that you have no idea how the US enriches uranium, or the difference between a power pressurized water reactor and a fast "breeder" reactor (if you were thinking of plutonium) or a centrifuge.
The US enriches uranium using a gas-centrifuge. The US also no longer recycles spent nuclear fuel, but France does.
redacted
Nuclear plants don't enrich. Enrichment would happen without power plants. Bomb fuel and power fuel are not the same.
Not trying to be "difficult," but isn't that what people thought about coal/oil at first? I understand that the scale is different, but it still needs to be a stop gap as opposed to a long term plan.
Spent Nuclear Fuel, unlike coal or oil, can be recycled to a certain extent (this is done in places like France but not the US). If we recycled all of the spent fuel, we'd potentially have a thousand years (give or take) of fissionable fuel. Plenty of time for us to get fusion running so we can completely wean ourselves off petroleum energy generation.
billions if we start using thorium
So far the problem, if I understand correctly, is all thorium reactors are molten salt reactors. The issue there is, we still haven't solved the metallurgy problems of dealing with the corrosive salt. It destroys all the pipes. We have slowed it down, but not enough to go production with.
How fast are talking. Like replace the pipes evety year or they breakbdown in months
I don't have an answer for that question unfortunately
By that time I'm hoping we'd be using Deuterium-Tritium fusion for all our needs. Or go full scale megaengineering and Dyson Sphere some star somewhere.
Why do you think we need nuclear to transition fully off petroleum? Renewables with storage are cheaper today for new build power, let alone in another 20 years. They continue to get cheaper and more efficient quite rapidly.
Because renewable depends on the weather, while nuclear doesn't.
A mix of renewable is absolutely a good thing to do, but still, having a constant source of energy mixed with that ensure stability.
The storage problem is the limiting factor. Batteries are wildly too expensive, pumped storage takes a huge amount of space and isn’t feasible in most places due to geography, and hydrogen is not nearly there yet technologically.
If we switched entirely to wind and solar we would need to accept total shutdowns when we had a bad run of weather.
last time I checked the renewables being installed didn't even offset the new energy demands being created, let alone making a dent in starting to decarbonize existing demand.
and the main reason is, that we need to tackle climate change from as many angles as possible and not eliminate a fine energy source just because something else is cheaper.
I mean for now renewables are cheaper, do you think we have enough raw materials to cover all of earths energy needs?
what happens when the raw materials will start to run dry but we still need to cover a bunch of energy needs, is that when we dust off the good ol Nuclear plants?
not to mention Nuclear plants provide a stable base load, no need for smart electronic devices that use power when it's most abundant etc. it's just power, that runs, constantly.
I think the issue is batteries, which are expensive and require rare earth metals which often have environmentally costly acquisition methods. Perhaps an optimal solution would be a baseline of nuclear power, and then enough renewables to meet peaks in demand. That way we have plenty of stable energy while minimizing nuclear risks.
When you get into power say a whole large city the batteries cost more then the solar panels. Especially in more polar places like Juno Alaska where you need to store a surplus of power for months. plus batteries degrade over time so they would have to be replaced. That's part of the reason why ion flow batteries are being researched, you can just drain them and replace the fluid*.
I didn't know about those. I'll have to look more into it. Thanks!
You're conflating leftover dregs of Pu-239 (about a 10-15% boost in energy per fuel input) with non-fissile material like U238. Breeder reactors required to use the second have never been used commercially in breeding mode.
You've either fallen for or are intentionally spreading a lie.
What lie am I spreading? Conventional Light Water Reactor Nuclear Fuel (5-6% U-235 w/t%) can be recycled. This can be done even without using breeder reactors which operate through fast fission of U-235
Yes the plutonium can be stripped out along with the other transuranics, and it does pose a proliferation risk (separate issue), but it definitely can be recycled. France reprocesses their fuel.
Edit: typo correction
Ah. So intentional then. You're trying to pretend extracting the <0.7% left over U235 and Pu239 (for a 10-15% increase in U235 fuel economy) is somehow fissioning U238.
I don't understand what you're trying to say here. Reprocessed fuel does not imply that we're now fissioning U-238. That takes place in a completely different energy regime (fast fission vs. thermal). Light Water Reactors and fast reactors operate differently, with different fuels. LWRs in commercial operation use slightly enriched U-235. There is no fissioning of U-238 other than the very small amount of spontaneous fission which is negligible compared to contributions from thermal fission in an LWR. The Six Factor formula governs criticality reactions, and these terms differ for both reactor types. The nuclear cross sections are fundamentally different between these energy regimes.
Reprocessed fuel is what it implies, recycled processed LWR fuel, stripped of the fission products that built up as the fuel underwent burnup in the core. If this were some sort of pretend activity then I guess the entire reprocessing back end of the nuclear fuel industry is fake.
I don't appreciate the personal attacks, so if you have nothing constructive to say, good day to you sir slash madam.
You're still trying to spread the "90% of nuclear waste is recyclable" myth, but now you've retreated to the bailey of "getting 10% more energy is technically getting something out of it so saying it is recyclable is totally true even though this has no impact on mining or the dangerous parts of waste!!" You're also pretending it magically makes the Pu240 and Am241 go away.
Reprocessing yields a small fraction of leftover fissile material. It is in no way characterisable as recycling.
The strategy is a very boring and tiresome propaganda move that is part of the Duke Energy and Rosatom astroturfing playbook. As is the "who me? I couldn't possibly be slyly trying to imply nuclear waste is actually fuel" act.
U-238 is largely stable and has the consistency of metal, making it easy to store or sequester away. Most natural deposits of Uranium are U-238.
Additionally you can make a breeder reactor that bombards U-238 to make U-239 which has a half life of 23+ minutes and decays into Plutonium-239 which can be used in nuclear power generation.
Not sure what you're even trying to say with the first bit. It's completely irrelevant
No breeder reactor has ever produced enough fuel to run on and extracted it. Breeder programs get as far as half of a proof of concept and then run out of funding on the actually hard part.
If we can pull off hydrogen fusion without crazy radioactive isotopes I reckon we can go on for a little while without having to worry about running out of hydrogen in the solar system / galaxy
Too bad the energy companies essentially never dispose of the waste properly, because it's too expensive if they want to give the huge bonuses to their CEOs and buyback thie stock. Even when doing it "properly" it's basically just making it the problem of future generations once the concrete cracks.
And to reprocess the waste and make it actually safe energy would mean no profit at all plus the tech doesn't exist yet to actually build the reactors to reprocess the waste. I mean we understand the theory, but it would take at least a decade to engineer and build a prototype.
Compare that to investing in battery tech which would have far reaching benefits. And combining that with renewables is much more profitable.
To be fair, nuclear waste tends to be disposed of much more properly than coal waste.
There's also orders of magnitudes less.
True, but still not anywhere near "clean" as it's always marketed as.
This is a stupid take.
Coal power puts out more radioactive waste than nuclear does, and coal sends it right into the air where we can't manage it.
Nuclear waste is kept solid, and contained. We know exactly where it goes and as long as the rules are followed it's not at risk of polluting anything.
Sure solar and wind don't have any by product once they are setup, but they also don't fit the baseline power need that nuclear does.
Problem is it's not profitable to follow the rules, and conservatives have blocked building a national "permanent" storage site for decades. The IS has no where to put it. It's just sitting in storage facilities, above ground and in many states in places where an earthquake could cause it to leak into ground water and make the area unlivable for centuries, or cost trillions to clean up.
https://www.scientificamerican.com/article/nuclear-waste-is-piling-up-does-the-u-s-have-a-plan/
Quite a large number of Republicans, including Trump himself, spend decades trying to ram Yucca mountain through. It faced heavy resistance from both the Clinton and Obama Administrations, the State of Nevada, and myriad of environmental organizations. Trying to blame it on "Conservatives" is pretty ridiculous.
https://www.ktnv.com/news/history-of-yucca-mountain-1982-2018
Yucca Mountain was killed by decades of persistent interference by opponents of nuclear power.
What makes you say that. Nuclear waste has the consistency of glass or sand depending on how it's processed. And if we reprocessed that waste like the French we could effectively remove the danger of it.
See earlier in the thread. The waste is highly radioactive, of course, and very hot for some time. First it is dumped in pools. If the pool floods or cracks, you end up with the Fukushima issue. Fortunately that went to the ocean primarily and so was diluted. But in the US, much of the country is landlocked and it would instead enter ground water.
Second, once the material is cooled enough to transport, it is supposed to be moved to a secure location, dropped deep into the ground, and encased in concrete. At this point if there are no earthquakes and water doesn't enter and damage the concrete, this will stay put for a thousand years or so, but eventually it will get out long before it's safe considering some of it takes around 250,000 years for it to decay enough to be safe.
As for what France does, as I mentioned, the US has not developed or built that tech because there is ultimately no profit in it and the US is unwilling to spend tax money on it. So it would fall to increased energy cost for the consumer in places where nuclear is used, and no one is going to like that. The cost of building the reprocessing facilities and doing the actual processing outweighs the value of the produced product. And building the first one is going to be the most expensive, and no modern energy company is likely to want to take the hit to short term stock prices in order to take it on. And conservatives won't approve tax increases at all in the current political climate. And progressive places have already started moving to renewables instead since it's cheaper.
First Ford, then Carter stopped commercial re-processing in the United States. Reagan brought it back. G. H. W. Bush then put the brakes on it but stopped short of an outright ban. Clinton stepped on the brakes even harder but again stopped shy of a full ban and when Bush Jr came into office he started a slow process of bringing it back. That's as far as this CRS Report goes although there may be an updated one somewhere out there.
Still, the US has spent money on it and was doing so at least as recently as 2008. It appears the biggest worry we have is proliferation of nuclear material, not profit or cost.
Not a single power source we have is clean
How is solar, wind, or hydro not "clean"? The generating of the power, not the building of the facilities, building anything is never clean.
~said the 1850s train conductor