The (nuclear) path not taken
December 21, 2009 6:23 PM   Subscribe

Nuclear engineers are never taught about the other kind of nuclear reaction. But a working prototype was built over 40 years ago. "The thick hardbound volume was sitting on a shelf in a colleague’s office when Kirk Sorensen spotted it. A rookie NASA engineer at the Marshall Space Flight Center, Sorensen was researching nuclear-powered propulsion, and the book’s title — Fluid Fuel Reactors — jumped out at him. He picked it up and thumbed through it. Hours later, he was still reading, enchanted by the ideas but struggling with the arcane writing. “I took it home that night, but I didn’t understand all the nuclear terminology,” Sorensen says. He pored over it in the coming months, ultimately deciding that he held in his hands the key to the world’s energy future."

LFTR in under 10 minutes. The Liquid Fluoride Thorium Reactor is an updated version of the nuclear technology developed at Oak Ridge National Labs in the '50s and '60s. The concept is inherently meltdown- and proliferation-resistant, and could lead to carbon-neutral energy production at about the same cost as current coal-fired power plants.

Lots more information can be found at the Energy From Thorium blog, and three Google Tech talks will give you a solid background on the subject. They're summarized in the 10 minute remix above:

* Dr. Joe Bonometti, 11/19/2008
* Dr. David LeBlanc, 2/20/2009
* Dr. Robert Hargraves, 5/26/2009
posted by Araucaria (76 comments total) 30 users marked this as a favorite
 
Now is the time to buy property in Un'goro Crater, Silithus, and Winterspring.
posted by aeschenkarnos at 6:26 PM on December 21, 2009 [20 favorites]


Here's a better link to the 10 minute remix.
posted by Araucaria at 6:27 PM on December 21, 2009


Uranium won out in part because it could be used to make plutonum based bombs? That's pretty crazy.
posted by boo_radley at 6:36 PM on December 21, 2009


Hmm. The idea of thorium reactors has been discussed around here, and Wired can be a little breathless talking about technology.

The basic problem, as I understand it, is that we already have all this infrastructure built up for uranium plants. The R&D costs and time for building a full scale thorium plant make uranium a better bet right now. That doesn't mean research shouldn't be done.

I'd rather see more research into fusion. Thorium may be more plentiful then U238, but we are never going to run out of hydrogen. The current designs for fusion reactors include tokamak and Stellarator designs.
posted by delmoi at 6:40 PM on December 21, 2009


I feel so...strange, and a little pathetic. A little happy, too. I had no idea thorium existed IRL.
posted by 3FLryan at 6:40 PM on December 21, 2009


I've always dreamed of writing an arcane textbook of (fictional) science and engineering that should not be. Unfortunately, I lack the creativity to come up with stuff like Le Boit Diabolique. If I had money and weren't lazy, I guess I could hire a team of crack science humorist specialists. It'd be something for hipster and goth engineers to keep around.

However, there's so much denailism and pseudoscience on the shelves, I'm worried people would just think my book was just another Kevin Trudeau's "Scientific Proofs and Theorems THEY Don't Want You to Know." Plus, you can pretty much pick up any book on homeopathy and get the same experience.

That said, it's cool to see alternate reactor designs going on. If this doesn't produce fissile fuel suitable for a nuclear bomb, we may just have a proper reactor we can trust developing nations with. They get cheap, green power, and we can sleep safely knowing the engineers won't sell the plutonium on the black market to Al Qaeda.
posted by mccarty.tim at 6:41 PM on December 21, 2009 [1 favorite]


boo_radly, Uranium won out because it was symbiotic with nuclear arms development. It gave the military cover to say that its nuclear technology had civilian applications. Plus there was profit to be made in nuclear fuel processing. So any investment in standard LWR technology could be leveraged into military contract work and visa-versa.
posted by Araucaria at 6:45 PM on December 21, 2009 [1 favorite]


If fusion research is such a gamble, why not have all the world's governments agree to produce gambling licenses that return 75% of the profit to an international pool of money that goes towards fusion research? After all, it's how many counties pay for schools and roads. And it's not taking money away from people. It's money the people give up of their own free will for an activity they should be smart enough to not participate in.

Plus, we're largely researching fusion for a "Get out of Human Stupidity" free card. We're burning oil frivolously with no regard for the future like the apes we are, so we might as well use our economist brains to find a way to get energy from the stupid. Then, we can gamble until the sun goes dark, instead of until we run out of oil.
posted by mccarty.tim at 6:46 PM on December 21, 2009


The best part is that LFTR shoots most of the anti nukies rational arguments out of the water. I find that some of them continue to oppose the most practical alternative energy because they don't believe that it is possible for a reactor to just blow up like Hiroshima.
posted by Megafly at 6:47 PM on December 21, 2009 [1 favorite]


Correction "don't believe that it isn't possible for"
posted by Megafly at 6:48 PM on December 21, 2009


Fuel input per gigawatt output: 250 tons raw uranium
I liked the article, but dumb unit-conversion oversights like this make me twitch a little. Just to put it in more familiar terms, this is like saying that a 150 horsepower engine requires 10 gallons of gas. You have a rate on one side, and an absolute quantity of fuel on the other. That doesn't compute. I suspect they mean GW*yr, or maybe GW*powerplant-lifetime, but you can't tell without additional information.

Pretty sloppy, Wired.
posted by Kadin2048 at 6:49 PM on December 21, 2009 [3 favorites]


[Re: Thorium. The old-style lantern mantels (for, e.g. Coleman camping lanterns) were thoriated and could, in shipping-container quantities, scare the crap out of people as thorium is a fairly mild alpha emitter (radon is a proximal decay product). I think you might have to go to China to find mantels that are still thoriated, but a fun factoid nonetheless.]
posted by Emperor SnooKloze at 6:52 PM on December 21, 2009 [1 favorite]


delmoi, I completely agree that we should proceed with current nuclear technology. It is ready to go right now and is carbon neutral.

However a moderate investment in LFTR (both standard and fast neutron designs) could be used to process traditional nuclear wastes into much smaller quantities that decay to background levels in 300 years. This would be worth pursuing if only to reduce the hazard of nuclear waste storage.
posted by Araucaria at 6:53 PM on December 21, 2009


Uranium won out in part because it could be used to make plutonum based bombs? That's pretty crazy.

I don't know.. A lot of countries have developed their own nuclear reactor technology, and not all of them were interested in building bombs. Actually, here is a list of Thorium powered reactors on wikipedia. It leaves me wondering where the whole "nuclear engineers are never taught about.." line comes from.
posted by Chuckles at 6:53 PM on December 21, 2009 [1 favorite]


Uranium won out because it was symbiotic with nuclear arms development.

In the US, there are other places though...

It gave the military cover to say that its nuclear technology had civilian applications.

Kind of like NASA and ICBM technology.
posted by Chuckles at 6:56 PM on December 21, 2009


I just love how we have this vast untapped power source -- which, aside from being incredibly abundant is also extremely clean and safe (when compared to the alternatives, anyway) -- yet there is no desire or funding to actually get things started because, hey, we've got our dirty, dangerous technology and it's working for us and turning a profit right now.

Ha ha. Oh, humanity. We are so fucking doomed.
posted by Avenger at 6:57 PM on December 21, 2009 [16 favorites]


Chuckles: It leaves me wondering where the whole "nuclear engineers are never taught about.." line comes from.. I apologize, it comes from me only. I was summarizing based on comments I've read over the last year from nuclear engineers trained in the US. This was probably overreaching because some schools in the US and elsewhere may indeed cover thorium technology. But my impression was that US university programs in nuclear engineering give cursory mention at best to Molten Salt Reactor technology.

My other comment is also IMO, not a statement of fact.
posted by Araucaria at 7:03 PM on December 21, 2009 [1 favorite]


A lot of countries have developed their own nuclear reactor technology, and not all of them were interested in building bombs

Not snark -- I had the same thought, then went through the list of countries with nontrivial nuclear energy production, and changed my mind. I am wondering which countries you are thinking are not interested in building bombs today and not interested in having the capability as a contingency plan.
posted by rr at 7:04 PM on December 21, 2009 [1 favorite]


btw, I should mention -- This list, from Wikipedia.. Start by excluding most NATO member countries (especially those that have tested), China, Taiwan, Korea, Japan and all former Soviet countries. The rest of the list is small deployments that very likely outsourced the development and ended up getting what was familiar.
posted by rr at 7:09 PM on December 21, 2009


I'm sorry, but I came into this being optimistic because, hey, engineering our way to sustainability! But then I discover that this technology is thrown under the bus, not for practical consideration, but because it just so happens that another technology is really good at making bombs. You can say, "That's just capitalism," or "That's just politics," but that's even more depressing. Those concepts run through America's very veins. If that's true, than we're truly screwed, and the country I love so very much (Yes, liberals can love America) isn't long for this Earth.

It really makes me wonder if the Coppenhagen summit is all just an act, and the world leaders are just looking for a way to weaponize carbon reduction.
posted by mccarty.tim at 7:09 PM on December 21, 2009 [1 favorite]


Ha ha. Oh, humanity. We are so fucking doomed.

Agreed.

I don't get how there is not money in this, nor what the huge tech hurdle is. Sounds like containing the highly corrosive fluid is the main problem? This can't be that hard.

I mean, there is big money to be made with a solution like this, if not in our backwards first-world nation, then in aspiring first-world nations the world over.

I feel like I'm missing a piece of the puzzle.
posted by maxwelton at 7:10 PM on December 21, 2009 [1 favorite]


Uranium won out in part because it could be used to make plutonum based bombs? That's pretty crazy.

Isn't it? Even crazier - people think that the movie Dr. Strangelove was fictional. The only thing fictional about it is the really crazy parts that they left out of the movie.
posted by loquacious at 7:11 PM on December 21, 2009 [5 favorites]


If this is so hard to engineer, how did we get the conventional reactors in the first place? And plutonium bombs? And the Large Hadron Collider for that matter?

Engineering is humanity's thing. If we can build a magical thinking machine that lets us near telepathically talk to anyone on Earth in under a second, and then figure out how to fit one in our pockets and run it from a battery, we can squeeze some electrons out of a rock.
posted by mccarty.tim at 7:15 PM on December 21, 2009


"Named for the Norse god of thunder, thorium is a lustrous silvery-white metal. It’s only slightly radioactive; you could carry a lump of it in your pocket without harm."

Is that a lump of thorium in your pocket, or are you just cultivating a new energy source?
posted by Smedleyman at 7:20 PM on December 21, 2009 [6 favorites]


People really, really like the being able to make bombs thing.

Would this be technically more difficult than containing liquid sodium?
posted by Artw at 7:22 PM on December 21, 2009


Two things to note on that list of thorium reactors linked above -- most of those appear to be retired experimental reactors and the remainder are quite small (though I guess calling 40MW small is all about context).

Though there are some quite impressive wind farms. Perhaps the "but this is america so of course we screw it up and do the irresponsible thing" crowd would appreciate the irony that not only are the majority of wind farms in the US, and the amount of power produced in the US dwarfs that produced by all other nations combined, but the big ones are in Texas, of all places...
posted by rr at 7:25 PM on December 21, 2009 [1 favorite]


Kind of like NASA and ICBM technology.

I'm really not sure that this is supported by the evidence. I mean, the military had their missiles before NASA existed. I'm pretty sure that nobody justified ICBMs by saying they could later be used by a civilian agency when congress got around to creating one. If anything, NASA was justified by the reverse argument, "Hey we got this great weapon! ...".
posted by kiltedtaco at 7:33 PM on December 21, 2009 [1 favorite]


If this is so hard to engineer, how did we get the conventional reactors in the first place? And plutonium bombs? Essentially America gained most of the major intellectual resources for doing these things by accepting eastern European refugees fleeing from the Nazis. Let me recommend THE MAKING OF THE ATOMIC BOMB by Richard Rhodes. It's very well written and makes the basic technical concepts very accessible.

Also, since we're talking of Thorium, scientists have found the first stable ultra-heavy element, provisionally referred to as unbibium, lurking in garden-variety samples of terrestrial Thorium.

Further, there was a mention upthread of fusion. I feel like this is as good a place as any to mention focus fusion (a.k.a. FOFU). These people have an aggressive, concrete timeline and funding for an ongoing program of laboratory prototyping and testing. I think they have a technology worth watching.
posted by newdaddy at 7:37 PM on December 21, 2009


Bussard's fusion plan is also one to watch (though he is dead). On FF, frankly, Eric Lerner comes across as a bit of a timecube guy and gives his own interest a bad name.
posted by rr at 7:39 PM on December 21, 2009


Megafly: The best part is that LFTR shoots most of the anti nukies rational arguments out of the water.

Assuming this is 100% true, and recognizing that the anti-nukies where at their most powerful in the 1980s and and 1990s, it makes it that much more difficult to understand why it hasn't already turned into a viable technology. There must be factors holding it back other than "uranium is more convenient and can be used in bombs".

rr: I am wondering which countries you are thinking are not interested in building bombs today and not interested in having the capability as a contingency plan.

Well, I was thinking of Canada, Nordic countries, and possibly Germany and Japan. Of course it is all kind of complicated.

Canada has a strange history around nuclear weapons, and reading that wiki link it becomes clear that AECL was a lot more a pawn of the US nuclear weapons industry than I realized. It should have been obvious.. Japan is equally ambiguous, in a different way. I've read credible sources that go further than suggested in that wiki article, saying that Japan literally has weapons ready for assembly on very short notice, but I've also heard credible opposing arguments. And ambiguous in yet another way, Germany has stationed American nuclear weapons. Unlike Canada and Japan, I don't see the direct argument for why Germany's nuclear industry should be beholden to military considerations.

That leaves "Nordic Countries" :) Sweden was clearly aiming for bombs too though. Which leaves Finland..

All this points strongly in one direction though. It seems that nuclear power just doesn't make sense economically unless it is highly subsidized by weapons programs. I'm on the fence about being an anti-nukie myself, but all this seems to be a strong anti-nukie argument to me.
posted by Chuckles at 7:41 PM on December 21, 2009 [2 favorites]


people think that the movie Dr. Strangelove was fictional. The only thing fictional about it is the really crazy parts that they left out of the movie.

That and the part about the entire world being blown up. That was also fictional.
posted by Ironmouth at 7:43 PM on December 21, 2009 [8 favorites]


We're talking about an elemant without a link to the appropriate Periodic Table of Videos vid?

I'll fix that. It's only 30 seconds long, but thorium is an element just like all the others. It deserves its video link, great or small.
posted by mccarty.tim at 7:45 PM on December 21, 2009 [1 favorite]


Also, since we're talking of Thorium, scientists have found the first stable ultra-heavy element, provisionally referred to as unbibium, lurking in garden-variety samples of terrestrial Thorium.

Don't always believe what you read on Slashdot: Heaviest element claim criticised
posted by XMLicious at 7:49 PM on December 21, 2009


Emperor SnooKloze: The old-style lantern mantels. . . were thoriated and could, in shipping-container quantities, scare the crap out of people as thorium is a fairly mild alpha emitter. . .

A friend of mine who works in a nuke plant likes to say, "milliREMS are your friends.
REMS -- not so much."

As a nuke employee, he's allowed 5 REMS per year. . .
posted by Herodios at 7:51 PM on December 21, 2009


[Re: Thorium. The old-style lantern mantels (for, e.g. Coleman camping lanterns) were thoriated and could, in shipping-container quantities, scare the crap out of people as thorium is a fairly mild alpha emitter (radon is a proximal decay product). I think you might have to go to China to find mantels that are still thoriated, but a fun factoid nonetheless.]

David Hahn got the Thorium for his backyard breeder reactor that way.
posted by Artw at 7:56 PM on December 21, 2009


Herodios: As a nuke employee, he's allowed 5 REMS per year. . .

Since radiation is a lifelong-accumulated threat, what that really means is that he is allowed 5*(# of years they expect a worker to have a career) REMs.

Shudder.

Which, if you live in certain uranium-rich areas of, say, the American West, you are going to get from the ground you walk on, anyway.

Shudder.
posted by IAmBroom at 8:03 PM on December 21, 2009


maxwelton: "I feel like I'm missing a piece of the puzzle."

Well, you're missing a few billion pieces of the puzzle — that's what's needed; several billion dollars of capital investment. That could, in theory, come from either the government or the private sector, but the private sector isn't really hot on anything that smells of research these days. They want marketability, and its consequent payoff, within a few quarters or at least on a very rigid timeline.

This goes doubly or triply for anything nuclear, because of the public opinion and politics you'd have to play. Even if you could come up with a working design, you'd still have to get it through the NRC's approval process and past the anti-nuke crowd, the latter of whom aren't constrained by logic or reason in many cases, and play directly to the public's emotions with their mushroom-cloud rhetoric and imagery.

Plus, the payoff is uncertain: if the technology really works as promised (carbon-neutral! too cheap to meter! bomb-proof!), who's to say that whatever patents you might have would be respected? The pressure on governments to just run roughshod over you, to sacrifice you and your investment for the public good, would be tremendous.

So on one hand, you have a large risk that it won't pan out and turn into a marketable product, at least within a short amount of time that investors are looking for. And on the other hand, there's the risk that even if everything did work out perfectly, that it wouldn't be monetizable because the demand would be so dire. Together, it makes it a hairy proposition for most investors; maybe there are a few rich people here and there that might be willing, but Wall Street in general probably isn't going to bankroll it.

On the government side, I see the barriers to funding being twofold: first is the general resistance to anything "nuclear," whatever it might involve. Although public perception may be turning, I can imagine a lot of politicians not wanting to have anything to do with "more nuclear power plants." Plus you just have a lot of competing priorities when it comes to funding. Carbon-neutral energy isn't enough of a priority in the U.S. to justify the dollars right now.

Perhaps at some point in the not-too-distant future, climate change will become a True Crisis, and there will be the right combination of public interest in carbon-neutral nuclear energy coupled with political will to fund new reactor research. But I'm skeptical that we're closer than a few decades from that crisis. Most predictions of climate change that I've seen put the burden on low-lying developing countries (e.g. Bangladesh), and the lives of foreigners have never counted for very much when it comes to U.S. politics.

I don't predict we'll see any real large-scale action (on the Manhattan Project scale that would be necessary to rapidly develop and build out new reactor designs for electricity production to replace fossil sources) until something occurs to impress on the public that climate change is real and that their way of life absolutely depends on funding the research. As long as the cost can be shoved off and borne by someone on the other side of the globe, not a chance.
posted by Kadin2048 at 8:11 PM on December 21, 2009 [3 favorites]


And i was jsut reading this this morning: "An LFTR deployment plan for Australia".

No offence to the usual worthies here on MeFi, but I reckon the debate over there will be more informed and useful than the one here, for those that want to engage with the numbers and physics rather than the politics.
posted by wilful at 8:14 PM on December 21, 2009 [2 favorites]


I don't get how there is not money in this, nor what the huge tech hurdle is.

There's not money in this because nuclear reactors have always been primarily government initiatives. There's no money in selling nuclear reactors because they can only be built, supported, and insured by a government willing to do so.

That, and there are only two reasons to have a nuclear reactor in the first place: you want to make bombs, or you are on a nationwide idealistic crusade to wean your country off of imported fossil fuels.
posted by deanc at 8:28 PM on December 21, 2009 [4 favorites]


Would this be technically more difficult than containing liquid sodium?

God, what is it with people and their bizarre fear of sodium! Why wouldn't you be able to contain it? It's melting point is lower then the boiling point of water! As long as it doesn't get wet, it won't explode!
posted by delmoi at 8:57 PM on December 21, 2009 [1 favorite]


As long as it doesn't get wet, it won't explode!

You also should avoid sunlight, and NEVER feed it after midnight.
posted by flaterik at 9:17 PM on December 21, 2009 [7 favorites]


I'd love for Oz to be a forerunner in safe nuclear power generation, but frankly we're all too busy running around shoving our collective heads up our arses to actually get something DONE. Oh, if only I had a spare AU$1bn lying around ...
posted by nonspecialist at 9:17 PM on December 21, 2009


As a nuke employee, he's allowed 5 REMS per year. . .

Well, not really. I mean, the limit is 5 Rem/yr (REM is also plural btw), but organizations are required to have a program in place to maintain exposure as low as reasonably achievable. My local control level, which could be extended up to 5 rem in small increments that become increasingly more difficult to justify and get approved, is 500 mrem/yr. Due to the strict exposure controls and good work practices in place, I have managed to accumulate 25 mrem this calendar year, which is almost over. A program that consistently maxes out all of its workers to the legal limits will quickly find itself in hot water with oversight agencies. (Disclosure: I am responsible for exposure control practices where I work.)

Which, if you live in certain uranium-rich areas of, say, the American West, you are going to get from the ground you walk on, anyway. Shudder.

Wouldn't that mean that the limit is very near natural background levels? Isn't that a good thing?
posted by ctmf at 9:33 PM on December 21, 2009 [2 favorites]


That and the part about the entire world being blown up. That was also fictional.

So far . . .
posted by flug at 9:35 PM on December 21, 2009


God, what is it with people and their bizarre fear of sodium! Why wouldn't you be able to contain it? It's melting point is lower then the boiling point of water!

Except that molten sodium and molten salt reactors operate at 650ºC-1400ºC or so. It's not just-barely-liquid sodium, it's blazing-hot, almost-boiling sodium. And in the case of molten salt reactors, it's white-hot and corrosive as hell to boot. Yes, such reactors can be engineered to be safe, but let's not pretend it's not a substantial challenge or that safety concerns are irrational.
posted by jedicus at 9:52 PM on December 21, 2009 [1 favorite]


What they did to Karen Silkwood is reason enough not to pursue nuclear technology. What caused TMI and Chernobyl are reasons enough not to pursue nuclear technology. The people who run these programs have demonstrated time and again that they have almost no regard for public safety.
posted by Blazecock Pileon at 10:12 PM on December 21, 2009 [1 favorite]


Was that a troll, Blaze? Because I'm wondering what industry you know of that has not had any accidents to learn from. I think the nuclear industry has been unbelievably safe to the general public, given the number of accidents over the age of the industry.
posted by ctmf at 10:25 PM on December 21, 2009




Only the one of them has blown up so far! The rest just had regular meltdowns!
posted by Artw at 10:41 PM on December 21, 2009 [2 favorites]


Oh come off it, stop the insanity, why you would bother mentioning Chernobyl in this thread is beyond me.

a. almost thirty years ago, in the USSR, based on a 1950s design.
b. caused by utter idiocy and incompetence on a grand scale, not witnessed anywhere else
c. It killed a lot less people than coal mining does every year
d. Is talking about a technology substantially different to the subject of this thread.

Mentioning chernobyl is about as relevant as mentioning the Ford Pinto when talking about modern car safety.

The people who run these programs have demonstrated time and time again that they have overwhelming regard for public safety. Hence the almost immaculate safety record.
posted by wilful at 10:50 PM on December 21, 2009 [11 favorites]


I am wondering which countries you are thinking are not interested in building bombs today and not interested in having the capability as a contingency plan.

Possibly, but also note that most countries developed their nuclear tech through deliberate strategic gifting by nuclear powers such as the Atoms for Peace program. This would tend to propagate existing weapons-tied tech rather than fostering alternative tech. The countries that would be interested in alternative tech would actually be the ones least likely to get gift tech, in a vicious circle again re-emphasizing weapons-tied nuclear development (see, e.g., Pakistan and India). Thus there isn't really a market so to speak for the alternatives.

I don't think, therefore, that the existence of widespread uranium reactor technology necessarily indicates that every country where you find it wanted a weapons capability in their back pocket. In fact, many of them only obtained the technology through strict IAEA monitoring programs intended to prevent such bleed-through.

Kind of like NASA and ICBM technology.

I'm really not sure that this is supported by the evidence. I mean, the military had their missiles before NASA existed. I'm pretty sure that nobody justified ICBMs by saying they could later be used by a civilian agency when congress got around to creating one.


I love NASA, but this is wishful thinking. The space race was all about military dominance, from Sputnik to Shuttle. In a less general sense it was about putting a peaceful public face on missile technology, and in yet another it was about ensuring a supply of rocket scientists and rocket building companies for the forseeable future.

It is certainly more than mere coincidence that Shuttle's two fatal accidents are both tied to design considerations forced on the program in its early stages when Congress effectively required NASA and the USAF to merge their rocket plane programs. The Air Force wanted a space station to spy on the Russians, and the capability to steal Russian satellites if necessary. It was only the Challenger accident that pushed the USAF back to the Deltas and the latter-day Atoms for Peace program that merged the Freedom and Mir 2 space stations into ISS, quite literally as a deliberate agreement between the Clinton and Yeltsin administrations to employ the Russian technical class so they wouldn't migrate around the world selling Soviet nuclear tech.

All the nice toys we get from NASA are spinoffs from its playing beard to the military.
posted by dhartung at 11:03 PM on December 21, 2009 [3 favorites]


If you read through the details of the thorium reactors actually built, listed in the Wiki article mentioned above, it doesn't sound so promising. For example, the German THTR-300 cost 2 billion Euros, was shut down for being too expensive to run, and will cost another 1/2 billion to finish shutting it down.

The only non-research ones running, in India, are being used to produce bomb grade plutonium.
posted by eye of newt at 11:06 PM on December 21, 2009 [2 favorites]


It gave the military cover to say that its nuclear technology had civilian applications.
...
Kind of like NASA and ICBM technology.


Sort of like The US Post Office and Cruise Missiles
posted by eye of newt at 11:10 PM on December 21, 2009


Just in case you missed it the first time around, A Review Of Criticality Accidents will make you blow milk out your nose.
posted by sixswitch at 11:24 PM on December 21, 2009 [1 favorite]


The big dumb booster rocket method of going to the moon won out over the Von Braun plan due to ICBM technology. NASA exists because after you have all this ICBM technology just laying around....
posted by Kid Charlemagne at 3:03 AM on December 22, 2009 [1 favorite]


In response to an AskMe post about thorium reactors last month, I spent some time thinking about the thorium fuel cycle. Shamelessly quoting myself:
The magical thing about uranium is that it goes critical all by itself. Natural uranium, sitting in the ground, has some fraction that spontaneously fissions and makes a few free neutrons. All you have to do is put enough uranium together that the best place for the neutrons to go is onto another uranium nucleus. A uranium nucleus eating a neutron breaks up, freeing two or three more neutrons; they are already in your pile, and so the best place for them to go is onto another uranium. It used to be that you didn't even need people.

Reactor folks talk about the "neutron multiplication factor," usually called k or keffective, which is the number of fission neutrons that go on to produce another fission. A heavy element like uranium or thorium has half again as many neutrons as protons; two fragments from the middle of the periodic table only want to have about 20% more neutrons than protons; this is why you get a few free neutrons from a fission. An "average" fission in U-235 makes about 2.4 neutrons. It took one neutron to induce the fission, so if all the fission neutrons made other fissions you would have k = 1.4 and a runaway reaction. Your reactor must contain some material that eats 0.4 neutrons per fission, and it should be possible to add or remove this "neutron poison" as different parts of the fuel burn faster or slower.

To induce fission on Th-232 takes two neutrons: one to initiate the sequence Th-233 → Pa-233 → U-233, and a second to induce fission in U-233. If thorium reactors exist, U-233 must produce more than three neutrons per fission. But now there is a much bigger variation in the amount of control that's needed. Early in the fuel cycle you need a neutron source, which is usually enriched U-235. The protactinium takes weeks to decay to U-233; during this time you'd like it to be out of the neutron flux, since it apparently likes to send off an extra neutron and turn into the nastier U-232. Finally your U-233 has to be dense enough to sustain a reaction, and you need some neutron absorber to control its rate. If the protactinium decay were faster this would be a nice little system. As it is, it sounds pretty touchy.

Thorium reactors are probably doable in the long term. But sustaining a reaction is much more complicated than simply assembling a pile of enriched uranium, and politically the "simple" reactors are hard enough to build.
posted by fantabulous timewaster at 3:53 AM on December 22, 2009 [1 favorite]


Yay, another technology which, like fusion, will be perpetually 25 years away from commercial operation.
** raises hands weakly to shoulder level **
posted by scruss at 5:04 AM on December 22, 2009


I enjoyed reading The Fusion Quest recently, even if it is a bit out of date; I gained a lot of appreciation for the slow but steady progress that's been made.
posted by Wolfdog at 5:12 AM on December 22, 2009


Japan is equally ambiguous, in a different way. I've read credible sources that go further than suggested in that wiki article, saying that Japan literally has weapons ready for assembly on very short notice, but I've also heard credible opposing arguments.

Japan is, for all intents, a nuclear power. The *only* question is "do they have masses of weapons grade plutonium already refined?" Everything else they have -- the electronics to control and detonate, the machinery to make the precision parts needed, the reactors to create the fissionables -- and the missles to launch them with.

Really, it all just a matter of time. How long? A year, if they spent no time thinking about this, to days, if they've already built the parts and just need to take Pu from stockpile and assemble.

However, the big question is why. Japan as a nuclear power against Russia had a problem -- too close, no warning. Nowadays, the only credible threat is North Korea, which probably has a bomb, but has very limited delivery systems, and is ruled by a nut who deterrence might not work against.

But on a technical level, you have to consider Japan a nuclear power on almost any timescale except "today". The moment the government wants it, there is nothing to slow them down. An analogy. They're holding A♥ 10♥ J♥ K♥ Q♥, all the need to do is reorder the hand and they'll have it.
posted by eriko at 5:36 AM on December 22, 2009 [2 favorites]


Correction "don't believe that it isn't possible for"

Megafly, that's the kind of meltdown you get when your sentence reaches a critical mass of negatives. What's wrong with writing "they believe that it's possible for..."?
posted by Kirth Gerson at 6:53 AM on December 22, 2009


>They're holding A♥ 10♥ J♥ K♥ Q♥, all the need to do is reorder the hand and they'll have it.

Can't read my... can't read my... No you can't read my half dead face...
posted by mccarty.tim at 7:08 AM on December 22, 2009


China, North Korea and Russia all have long-standing beefs with Japan, due to its imperial past and current land claims. The not-really-but-yeah-really nuclear program is in place for if/when Japan cannot depend on the US to provide a credible deterrent.

What I find more interesting is that Taiwan probably has at least one nuclear-armed missile... they were part of a mutual defense technology pact with the other two "pariah" nations of the '70s, Israel and South Africa, both of which have or had nukes.
posted by Slap*Happy at 7:32 AM on December 22, 2009


>
Australian Engineering. ducks
posted by mccarty.tim at 7:32 AM on December 22, 2009


What caused TMI and Chernobyl are reasons enough not to pursue nuclear technology. The people who run these programs have demonstrated time and again that they have almost no regard for public safety.

that's funny, because I thought the argument against nuclear power was that experience showed that to make it safe, it cost more than it brought in.

American nuclear power has had only one serious accident in its entire history. They haven't solved the waste issue yet, and for that reason, I'm thinking it isn't the best idea for the US right now. But there's no need to go overboard.

As for "the people who run these programs," its kind of hard to equate Soviet Communism with US energy corporate executives.
posted by Ironmouth at 8:55 AM on December 22, 2009


Was that a troll, Blaze? Because I'm wondering what industry you know of that has not had any accidents to learn from.

I would rather learn from the accidents that have already happened with nuclear technology, from criticalities to meltdowns to plant explosions. There's a lot to learn there that has been ignored.

That said: My God, the kind of breathless writing in the Wired piece really should immediately trip people's bullshit meters. It's not really much different than 1950s Popular Mechanics writing, in that regard, namely an atomic age promising pie in the sky, smiling white, suburban families flying around in jet packs and popping food pills.

You're being sold a bill of goods by a nuclear industry that could be trusted, if it wasn't about private contractors fucking over taxpayers for the bottom line, doing sloppy work that puts people's lives in danger and then murdering the ones who know too much about the slop, and accidents that continually show how dangerous this technology, in fact, is, despite nuclear technician cheerleaders going rah-rah-rah on the Internets.

I think the nuclear industry has been unbelievably safe to the general public, given the number of accidents over the age of the industry.

Quantity of accidents divided by time has never been and will never be any kind of reasonable measure of safety for this technology. As we've seen, it takes just one accident to kill and sicken a lot of people and make land uninhabitable for thousands of years.
posted by Blazecock Pileon at 9:34 AM on December 22, 2009 [1 favorite]


As we've seen, it takes just one accident to kill and sicken a lot of people and make land uninhabitable for thousands of years.

All power sources have drawbacks. You are ignoring the problems of coal (the single largest source of radionuclide pollution by a huge margin) and fossil fuels in general and the costs of doing things with various forms of alternative energy.

In short, you are making a very common mistake -- you are comparing the risk of a very rare and unlikely catastrophic scenario against risks you are not bothered to perceive and judging the former as a major issue.
posted by rr at 1:08 PM on December 22, 2009 [1 favorite]


Araucaria: read further: "Fluoride salts naturally produce HF when in contact with moisture, which may lead to release of hydrofluoric acid fumes during reactor shutdowns, decommissioning, or flooding." Hydrofluoric acid is extremely nasty stuff.
posted by jedicus at 1:50 PM on December 22, 2009


"I feel like I'm missing a piece of the puzzle."

If it sounds easy and clean and safe and too-cheap-to-meter, you're probably missing several pieces of the puzzle.

After 50 years of living with nuclear energy ... and its many many many drawbacks ... and the -endless- lies and streams of deceptions used to keep it afloat - I've (only a little) surprised to hear people going "Oh, that sounds easy, let's do that." If it was so easy, wouldn't your 'free market' have capitalized on it long ago?

If all of us fruit flies weren't stuck in the same, capped bottle, I'd say "Go ahead". Just so that I could enjoy a sad smirk 20 years down the road.
posted by Twang at 2:21 PM on December 22, 2009


You are ignoring the problems of coal (the single largest source of radionuclide pollution by a huge margin) and fossil fuels in general and the costs of doing things with various forms of alternative energy.

In my considered opinion, it is manipulative and foolish to use global warming and other environmental issues as a means to promote nuclear energy, while at the same time discounting very real operational safety concerns, given prior experience, as complete non-issues, as is happening in this thread (and in prior threads regarding this subject).

That's looking aside ecological issues such as the scarcity of nuclear fuel and the environmental and health costs associated with retrieving it, the inability of nuclear energy to meet demand to significantly eliminate coal and other fossil fuel consumption, and the lack of secure and safe waste storage facilities and procedures.

you are comparing the risk of a very rare and unlikely catastrophic scenario against risks you are not bothered to perceive and judging the former as a major issue.

Civilian and military nuclear accidents are not "very rare" or "unlikely". Private energy contractors have shown non-compliance violation after non-compliance violation of basic safety and security procedures. The United States government, in turn, has shown that it has no teeth to maintain safe oversight of existing nuclear energy facilities and little will to enforce laws. Whistleblowers have their lives destroyed, if are not "suicided" outright.

We can't even properly manage the nuclear technology that we have now. I can't imagine what the costs will be from expanding it, if prior experience is worth anything.
posted by Blazecock Pileon at 2:30 PM on December 22, 2009


Since we're talking about power reactors and not weapons or nuclear medicine, we can remove all but power reactor incidents from your sensational lists. Furthermore, if we remove all of the incidents that didn't significantly affect the general public, those lists then get pretty short.

...accidents that continually show how dangerous this technology, in fact, is,...

Powered flight is pretty dangerous, too, I guess you would say then? Because it sure seems to me that the aviation industry is wiping out people at a rate the evil nuclear handlebar moustache villains must be pretty envious of.

And then I'm done, because if you're emotionally convinced that nuclear power is evil and the corporations' goons are all out to get us, then no amount of argument based on statistics or risk analysis is going to do anything but waste our time.
posted by ctmf at 6:54 PM on December 22, 2009 [3 favorites]


I take part of that back. The lists themselves aren't sensational; they are what they say they are. They just don't illustrate what you're asserting.
posted by ctmf at 7:32 PM on December 22, 2009


Furthermore, if we remove all of the incidents that didn't significantly affect the general public, those lists then get pretty short.

Didn't somebody mention coal miners dieing? And the link between civilian and military nukes has be illustrated very thoroughly already, so...
posted by Chuckles at 9:13 PM on December 22, 2009


In case anyone is still reading this: Joe Bonometti states pretty much the same thing as my header [paraphrasing] "I have a masters in nuclear engineering and we had only about 10 minutes of discussion on thorium in my entire education" in both the original Google Talk and the 10 minute remix. Sorry I could give attribution earlier.

The main thrust of these articles is that liquid nuclear cycles are fundamentally different from traditional nuclear reactions using solid fuel. Continuous reprocessing is simple chemistry, not an arduous industrial process. U-233 fissile material is contaminated with U-232 [gamma rays interfere with electronics and ar, making it impractical to use in nuclear devices. The reaction is passively stable and operates at normal atmospheric pressure. High temperatures mean that an efficient Brayton cycle gas turbine can be used instead of a liquid turbine. So comparing this kind of nuclear power to U-235 or U-238 with LWR is not really applicable.

Yes, it is going to require a couple of billion dollars of investment to get this going, and there are some difficult problems still to work on. I would compare it to the construction of the Bonneville Power Authority in the 1930s. Enormous dams were constructed on the Columbia river at great cost. They were large industrial projects that required huge amounts of capital (monetary and political) to get started, but they have been running for 75 years with low sustaining costs [Yes, I am aware that there was a large environmental impact but this is a general idea not an exact parallel. And hydroelectric is carbon-neutral, after all]. This kind of investment is not something that private industry is going to initiate, but there is tremendous public benefit and it is worthwhile for government to get it started.
posted by Araucaria at 11:25 AM on December 23, 2009


bleah. "Sorry I could *not* give attribution earlier". and "gamma rays interfere with electronics and *are difficult to handle safely*".
posted by Araucaria at 11:27 AM on December 23, 2009


Unfortunately the waste is also contaminated with U-232 and difficult to handle safely.

It's a complicated problem.
posted by fantabulous timewaster at 4:43 PM on December 23, 2009


Regarding my earlier comment about the statistics (fuel consumption and power output) being a bit suspect, they are most definitely not talking about the actual fissile fuel consumption. Here are what those numbers are, for comparison:
The fission of a single uranium-235 (or similar) nucleus is thus accompanied by the release of over 200 Mev of energy. This may be compared with about 4 ev which are released by the combustion of an atom of carbon-12 […] Alternatively, it may be stated that 1 pound of fissile material should be capable of producing the same amount of energy as 1400 tons of 13,000 Btu/lb of coal. […]

A useful fact to remember is that the power production corresponding to the fission of 1 gram of material per day would be roughly 104 watts, i.e., 1 megawatt. The mass consumed is, however, greater than 1 gram because some of the fissile nuclei are lost as a result of non-fission capture reactions.

from Glasstone, S., Sesonske, A., Nuclear Reactor Engineering, 1967. §1.44 - 1.46.
The actual true fuel consumption of a nuclear reactor, even a large one, is fairly small, on the order of a few kilograms per fueling. The only way Wired is getting anything close to the number they are quoting is by counting as consumed the mass of the entire fuel assemblies, which include not only the actual (fissile) fuel but also a lot of cladding and then all the nonfissile 238U that's just along for the ride and occasional neutron.

All of that is only "consumed" (in the sense of ending up as waste) because we don't currently reprocess it; an optimized uranium fuel cycle — which would be a fair comparison, since the thorium fuel cycle they're comparing it with is practically hypothetical — would have much better-looking numbers. So they're definitely engaging in a little number-massaging there.

Incidentally, if thorium reactors were dropped from the nuclear engineering curriculum, it happened after 1967, when my copy of Glasstone was published: it contains a fair bit of information on the subject, including a section on the properties of thorium with notes on its its properties in relation to molten-metal reactors. It spends about as much time on thorium as a reactor fuel (§8.91) as it does on plutonium, and is in no way dismissive. Perhaps this changed in later editions as the technology matured and emphasis was placed on dual-use technologies, but I found the datapoint interesting.
posted by Kadin2048 at 11:31 PM on December 26, 2009


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