On Thorium Power (and the 'hype' thereof)
I've noticed, particularly on reddit but also elsewhere on the english-speaking internet, that thorium nuclear (MSR/LFTR) power is being hyped. And I can't help but feel suspicious. It seems too good to be true. "burns our nuclear waste", "infinite fuel", "Absolutely safe", "Proliferation is not an issue". Stuff like that. Not gonna provide much evidence for those claims existing here, but I'll say that you can usually find them in any big thread involving energy sources and there's a few TED talks too. Coal, conventional nuclear, renewables, any of those is apparently strictly inferior and we're complete morons for not switching already. Coal apparently causes more damage through radiation than nuclear, nuclear is dirty and renewables need something... anything.. to keep them company in case we can't get enough wind/sun. (Also, batteries and hydroelectric storage don't exist.)
German wikipedia has this to say about thorium hype: "Der MSR/LFTR als Teil einer Thoriumnutzung erhält etwa seit dem Jahr 2010 insbesondere im angelsächsischen Raum starke Unterstützung verschiedener Organisationen, während Nuklear- und Energieexperten eher zurückhaltend sind. Einige dieser Befürworter halten den LFTR sogar für die Lösung fast aller Energieprobleme.[2][3][4][5] Kritiker sprechen aus unterschiedlicher Motivation heraus vom MSR- oder Thorium-Hype[6] oder sogar von Astroturfing[7]." - https://de.wikipedia.org/wiki/Fl%C3%BCssigsalzreaktor - paraphrased: MSR/LFTR received strong support in english-speaking areas by various orgs, while nuclear- and energy experts are mostly silent. Some supporters regard LFTR as solution to all energy problems. For various reasons, critics call thorium hyped or even astroturfed. [citations are mostly english, for the curious]
Meanwhile, there's major problems regarding practicality, we can't estimate just how secure it is (keep in mind modern reactor concepts are all "theoretically safe" as long as you keep the human out of the loop and maintain the facility properly.) Proliferation risks of thorium fueled reactors are immense due to U233 (232-contamination doesn't make the weapon less dangerous when used, just more dangerous to handle.). Also, no serious evidence for the capability to burn nuclear waste. And decommissioning a thorium plant seems, as of now, to be just as much of a shit job as a conventional nuclear plant - if not worse.
My main question with this is: How do you view thorium power / did you notice the same trends as I did? I'm just trying to form a conclusion between the hype and a maybe cynical pessimism.
Bill gates and the chinese backing it is a good argument. Both are "institutions" that seem to base their actions more on facts over hype.
Forgive me for not digging too much into the WNA's summary right now (I plan to later), as it seems to be a lobby organization of the nuclear industry - they have a stake here and would probably be part of the suspected hype generation machine.
My first thought about the safety assessment was that it was only looking at LWRs as comparison. But most new plants are PWRs, a subtype thereof, so fair enough, I'll accept it with a grain of molten salt. However, it admits the same caveat that de.wiki notes: No PSA yet. And it seems a PSA only covers known unknowns; it assesses failure modes we can anticipate, which is -to me- not very calming for a highly dangerous emerging technology. I'm also unsure whether a PSA covers the craziness of actually running the damn thing including lack of maintenance and human errors; considering these will be run by commercial operators, maintenance might suffer.
Waste management: This reads like a recipe for splitting the actually radioactive compounds from the "boring" salts involved. Storing the radioactive stuff in a glass body sounds not too bad, but my intuition tells me the actual messiness of the damn things is not going to be the spent fuel, same as with conventional nuclear. The next paper however mentions dissolving the nasties at "10−3 g/m2" - which sounds to me like they're measuring how much nasties were dissolved per surface area of glass dust. What kind of mass-specific surface areas could we expect for this glass given what kind of storage methods?
Also, is there anything to back up the claim that we can just pour radioactive waste into such a reactor or is that one BS?
Completely ignoring the specificity of thorium, it is my oppinion that humanity has been handicapped by resistance to nuclear energy. We have done far more damage to this planet with oil and other combustible energy sources than even the worst nuclear disasters.
Maybe. Consider that nuclear has been a vanishingly small part of worldwide power generation, and coal made up the bulk for a century. The fact that coal did more damage over that time period is unsurprising. (https://en.wikipedia.org/wiki/World_energy_consumption)
I do not know what would've been if we went for nuclear straight away and in full force. The pile of waste would be larger, and likely still as unsalvageable as it is now. If we had 10x as much accumulated nuclear energy production by now, we might expect 10x as many large accidents. We might also presume less than that because of a better safety record due to more experience. Or we might expect even more than 10x because accidents become more normal and thus safety is taken less seriously, degrading the safety culture if you will. My bet is on slightly less than 10x.
I don't have the answer. (Well... if you press me for one, I'll say renewables and fusion research.) But I do know that we haven't even begun cleaning up the nuclear mess we made. I don't think fission nuclear is sustainable at all. The sheer amount of waste is what kills it in my book, at least as long as we don't have a realistic storage option yet. (Keep in mind my Germany-centric perspective. The US might have a easier time storing it, both legally and geographically.)
Even if you take the most gratuitous numbers for all of the people killed in nuclear disasters since 1945, and multiplied them by ten, you wouldn't be anywhere near the annual death toll from coal. And that's just mining and related air pollution deaths, not even factoring in all the future deaths from global warming. Nuclear power occasionally kills people in once in a generation accidents, coal (and all fossil fuels for that matter) kills tens to hundreds of thousands annually when working as intended.
The damage from combustion exhaust is part of it, yes. But the thing that was forefront in my mind when I brought that up was the two giant oil spills that happened only within the last decade. I remember reading that the Deepwater Horizon spill was supposed to be the worst ecological disaster in history - worse than Chernobyl - and the Keystone pipeline spill is supposed to be even worse than that. And if you think that we have a problem cleaning up nuclear waste, just remember how poorly we took care of the Gulf of Mexico.
I'm aware nuclear power isn't perfect. But at the same time, it feels that the world just gave up on it in search of easier answers. The US literally decided to just bury nuclear waste before we threw in the towel instead of finding something better to do with it.
Our record on waste handling isn't stellar. For example: https://en.m.wikipedia.org/wiki/Hanford_Site
I have to keep reminding people that "risk" is the likelihood something negative will happen multiplied by the magnitude of harm if it occurs. With nuclear power technologies, we keep screwing up on risk vs benefit by locating reactors near population centers, failing to socially insure the full cost of disasters, understating the real costs of the nuclear fuel lifecycle, ignoring distribution losses from highly centralized generation, and so on.
While nuclear power is a potential remedy for greenhouse gas emissions, and no one should underestimate the cost and risks of climate change, it's reasonable to demand an accurate accounting.
Oh, thorium hype has been kicking around for a decade or more. It's just that some plutocrats are suddenly trying to green up and promote nuclear power as a way to maintain energy consumption without baking the planet via CO2 emissions, so the chatter level is rising.
There's a good summary here of why thorium is just one nuclear power option, not an especially good or bad one:
https://whatisnuclear.com/thorium-myths.html
This site has some good general information on nuclear power and generation methods.
The proliferation problems de.wikipedia talks about are related to Uranium 233 - which is even "better" weapons material than plutonium: "Durch kontinuierliche Abtrennung von 233Pa (Halbwertszeit: 1 Monat) lässt sich im LFTR relativ reines, also 232U-armes, hochwaffenfähiges 233U gewinnen.[49][50] Diese Abtrennung von 233Pa ist – aus Gründen eines möglichst effizienten Betriebs – in vielen LFTR-Varianten sogar vorgesehen und wurde im Rahmen der MSBR-Entwicklung im Labormaßstab getestet."
"By continually extracting 233Pa, a LFTR can generate low-232U, highly weapons grade 233U. This extraction of 233Pa is -for the sake of efficient operation- even designed into many LFTR-Variants and was testet at lab scale when developing MSBRs."
That kinda sounds like the problem is not plutonium.
No..? As I said, you split off the 233Pa and let it decay to 233U. Gun-design, there's your nuke. Or if you're a terrorist you don't really care about the 232U messing up your men, you just wanna fuck shit up anyway, then any 233U you can find is good enough. I can't seem to find much on how to actually pin down the location of a hard gamma source, so that one's hard to verify.
Ninja: I'll admit that it seems like a less than optimal choice for already nukified countries.
NinjaNinja: http://scienceandglobalsecurity.org/archive/sgs09kang.pdf indicates that 232 doesn't start to radiate hard-gammas immediately; rather, that only happens after a few months. It also points out that a Gun-design is possible with U233.
So you're claiming that 233Pa can't be extracted? Because that seems possible apparently. You seem to be dodging my argument.
Because it's not all that hard. Here, I tracked down the original source of the MSR-era research on Pa removal:
http://moltensalt.org/references/static/downloads/pdf/ORNL-TM-1543.pdf - that seems like you just need ThO2 or similarly easily obtained chemicals. That crashes out the Pa, and you redissolve that for further processing. That doesn't seem too hard to me.
As @vektor indicated, if you're reprocessing anyway, it's not that difficult to pull protactinium-233 and let it decay to nearly pure U-233. U-233 has advantages in weapons over U-235 if you don't have to worry about U-232; it is a proliferation risk when you've got nation-state resources to make this happen.
Plutonium isn't the only proliferable weapons-grade material, though - as the material notes, you can make bombs out of U-233, which is easily refinable from thorium/MSR processes. I'll freely acknowledge, though, that there's a safety benefit from not producing plutonium, which is a deadly material whether used to produce bombs or not.
Okay, further research; U-233 wasn't a serious bomb-grade material due to inevitable presence of U-232, which is a vicious gamma-emitter, and would likely make any transport extremely detectable, as well as dangerous.
Addendum here on proliferation risk and safety hazards of U-233/232 [PDF warning] - http://fissilematerials.org/library/sgs09kang.pdf
That is some nasty sh*t - gamma exposure from U-232 decay chain is much, much worse than from plutonium, and I'd not want to work around anything that might release it.
I had some radiation safety work in grad school, and wound up interviewing at the Hanford Nuclear Reservation.
There's a long, long process underway to clean up pits full of millions of liters of waste - estimated at around 2 x 106 Curies. The position would have involved designing hardened sensor technologies for monitoring that hell's brew, which consists of just about every possible isotope on the periodic table, not counting corrosive chemical properties. They couldn't make any sensor or camera to see what was happening in the tanks which would last more than an hour in that hard radiation flux.
Which brings me back around to an extension of your position. Proliferation or not, U-233/232, even in a closed thorium/molten salt cycle, is going to be hard to monitor, dangerous to work with, will require long storage to handle safely for disposal, and generally makes thorium cycle reactors less attractive than the hype would suggest.
Not necessarily less attractive than uranium, MOX, or heavy water reactors, but not free of the causes for public safety concern which have dogged nuclear power use.
I really wish the history of nuclear power wasn't so intimately tied to the history of nuclear weapons.
PDF warning - Thorium breeder cycles might have gotten off the ground much faster if plutonium production in fast breeder reactors hadn't been a priority for weapons production.
Military weapons production and nuclear waste disposal were recklessly casual affairs, they distorted and diverted civilian nuclear development, and will darken the safety record of nuclear power indefinitely. I don't know that the U.S. has transparent systems for chemical fuel processing capable of providing public safety assurance, or non-proliferation/arms certification.
Also see my comment adjecent to yours on how U232 contamination is apparently not that inevitable.