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Is Safe, Green Thorium Power Finally Ready For Prime Time?
MrSeb writes "If you've not been tracking the thorium hype, you might be interested to learn that the benefits liquid fluoride thorium reactors (LFTRs) have over light water uranium reactors (LWRs) are compelling. Alvin Weinberg, who invented both, favored the LFTR for civilian power since its failures (when they happened) were considerably less dramatic — a catastrophic depressurization of radioactive steam, like occurred at Chernobyl in 1986, simply wouldn't be possible. Since the technical hurdles to building LFTRs and handling their byproducts are in theory no more challenging, one might ask — where are they? It turns out that a bunch of U.S. startups are investigating the modern-day viability of thorium power, and countries like India and China have serious, governmental efforts to use LFTRs. Is thorium power finally ready for prime time?"
Why?
NIMBY
Chernobyl was a graphite moderated water-cooled reactor. Any commercial nuclear plant in the U.S. is a water-moderated and water-cooled reactor.
Despite the normal perception of the word, a "moderator" actually increases the nuclear activity in a fission plant since it slows-down ("moderates") neutrons and therefore increases the probability that the neutrons cause a fission event. In Chernobyl, the coolant (water) was blown away in the pressure explosion, but the moderator (graphite) remained in place which led to the runaway meltdown.
By contrast at Three Mile Island & Fukushima, the loss of coolant led to a meltdown (literally heat causing melting to occur), but since the water moderator was also missing, the accidents did not lead to a runaway that was anywhere near as severe as Chernobyl. If Fukushima had included a pressure vessel of the same caliber as the one used at TMI, then hardly any radioactivity would have been released during the Fukushima accident.
AntiFA: An abbreviation for Anti First Amendment.
Molten salt has a lot of advantages as a working fluid over water, unfortunately the major big disadvantage outweighs all the positives.
Viz. the conditions inside these reactors would be absurdly corrosive. F salts are chemically aggressive, and that aggressive increases with temperature. That is compounded by the fact that the reactor materials will also be bombarded with significant neutron fluxes, and by the presence of all dissolved decay products in the working fluid.
We simply don't have materials that can stand up for any length of time to that kind of abuse.
I have the misfortune of living at ground zero for an ongoing wind farm build. 24/7 truck traffic, massive clouds of dust, hour plus highway shutdowns while they move their superloads, obnoxious subcontractors that ignore traffic laws, etc, etc. Then there's the ecological impact -- acres upon acres of wooded hilltops have been deforested. I truly had no idea how obnoxious it was until Google Earth got updated images. Take a look at some before and after photos of a large wind farm and see for yourself how bad it is.
All of this might be worth it if wind energy scaled the same as nuclear, or could provide the same power density, but both of those are utterly impossible. You'll never match nuclear reactions for power density, and the footprint of a nuclear power plant is no larger than that of any other modern industrial concern.
Everything in life is a tradeoff, but having lived near Three Mile Island, and now living in the midst of a wind farm, I'd take the former any day of the week. You simply didn't know TMI was there, unless you happened to have cause to drive by it. Contrast that to dozens of wind turbines, visible for miles around, along with the obnoxiousness of their build process.
Nuclear and low impact hydro are the way to go for base load. Natural gas, along with wind, and solar for the peak load.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
Within microseconds of convincing any "environmentalist" that there is even the slightest possibility of a new class of reactor actually being built you will see the proponents vanish under thousands of lawsuits. Atomic energy is absolutely the only viable method of generating power without carbon emissions that we have, but it is not politically correct and a new reactor design not only won't change that, it will actually provoke a far more extreme response. Too much paranoia, too much stupidity, too much ignorance. It'll never happen, no matter how much it needs to. Americans can no longer deal with reality.
So there is a trope in the engineering world that the safest reactors are the ones that are confined to paper studies, or, to put it more timely, to PowerPoint slides.
It's true that the LFTR reactors don't have the same failure modes as the pressurized light-water reactors, but they still have the same basic issue, namely that there is a very large amount of power-generating capacity in a relatively small volume. Even pebble-bed reactors, similarly touted as "intrinsically safe" during their design phase, have had a radiation-release accident -- scroll down to "Criticisms of the design" on that Wikipedia page. The lesson (which I learned from Charles Perrow and Fukushima) is that complex systems with high power densities are intrinsically hazardous, because unexpected interactions (which arise from the complexity) tend to be highly destructive (because of the power density). LFTRs are less complex, and so less dangerous, than PLWRs, and that's good, but it doesn't make them safe.
The stupid cliche you hear over and over again is true -- safety is a process. You can design reactors so that the safety process is easier to implement, but what actually makes things safe is conservative management schemes that retain the redundancy and margin for error that the process demands, and not cutting them out because of the money, or, worse, because of complacency induced by faith in the design.
There's another industrial safety joke, particularly applicable to complex systems -- accident analysis consists of filling in X and Y in the phrase, "Nobody imagined X could happen whlie Y was true."
2*3*3*3*3*11*251
The title of your post asks a question, that question is What's-his-name law.
Since the law in question is "If the title asks a question, then the answer is no."
Therefor it is No's Law.
Don't know something? Look it up. Still don't know? Then ask.
Indeed, another great advantage of nuclear power is that whenever there's a catastrophic meltdown, we get hundreds of square kilometers of new wooded nature preserve.
So, what you're saying is, you don't like living next to a building site? What makes you think that subcontractors on wind farms are any worse in traffic than subcontractors on any other building site?
#shakes head#
I have the misfortune of living at ground zero for an ongoing wind farm build. 24/7 truck traffic, massive clouds of dust, hour plus highway shutdowns while they move their superloads, obnoxious subcontractors that ignore traffic laws, etc, etc. Then there's the ecological impact -- acres upon acres of wooded hilltops have been deforested. I truly had no idea how obnoxious it was until Google Earth got updated images. Take a look at some before and after photos of a large wind farm and see for yourself how bad it is.
Where is this exactly? Come on, don't just give us an unverifiable anecdote, give us hard facts that can be verified.
A properly designed wind farm shouldn't require mass deforestation or environmental damage.
const int one = 65536; (Silvermoon, Texture.cs)
SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
It is unsinkable.
Troll is not a replacement for I disagree.
The article indicates that Adm. Rickover didn't like molten salt / sodium cooled reactors because the "Navy knew how to handle water". In reality, Rickover's nuclear program tried both approaches. The Nautilus (SSN-571) used a boiling water reactor, and the Seawolf (SSN-575) used a sodium cooled reactor. Both were built, both went to sea, and both performed reasonably well. But the sodium-cooled reactor turned out to be harder to maintain than the boiling water reactor, and couldn't be run at full capacity because of some design problems. so after a year, Seawolf was returned to the yards and converted to a boiling water reactor.
That was very typical of the military approach of the period - fully develop several alternatives, operate them, then dump the losers. The history of 1950s jet fighters is a striking example.
Oh no. Nation states might do bad things using their custom designed expensive reactors.
In the production of U233 from thorium-232, it is unavoidable that one will invariably produce small amounts of uranium-232 as an impurity, because of parasitic (n,2n) reactions on uranium-233 itself, or on protactinium-233. Uranium 232 is really, really bad stuff.
The decay chain of U232 quickly yields a number of different strong gamma radiation emitters, which makes manual handling in a glove box with only light shielding (as commonly done with plutonium) too hazardous. Not only will it kill you dead, its presence will also poison your weapon yield, and it will alert anyone who cares to look exactly where your weapon site is.
The thing is, any nation (or terrorist group?) with the money and the resources needed could produce weapons more cheaply and with less risk to their workers by enriching U238 into Plutonium 239, which is much better for making weapons anyway.
I think the article is fear mongering at best. Is their a proliferation risk? Sure. An exceedingly impractical risk imho.
According to wikipedia:
Quote:
The United States detonated an experimental device in the 1955 Operation Teapot "MET" test which used a plutonium/U-233 composite pit; this was based on the plutonium/U-235 pit from the TX-7E, a prototype Mark 7 nuclear bomb design used in the 1951 Operation Buster-Jangle "Easy" test. Although not an outright fizzle, MET's actual yield of 22 kilotons was significantly enough below the predicted 33 that the information gathered was of limited value. In 1998, as part of its Pokhran-II tests, India detonated an experimental U-233 device of low-yield (0.2 kt) called Shakti V.
So it has been attempted, and seems to have badly fizzled with both efforts. The bomb makers with deep pockets have quite rightly given up in disgust. If some well funded terrorist group or nation state is going to bother with trying to make a bomb, they are going to buy or steal U239 or they will build themselves a uranium reactor, then frequently load and unload fresh fuel rods so they can extract plutonium. Nobody is likely to ever again give bomb making with U233 much additional effort.
Anybody trying to extract the Protactinium from a LFTR in the hope of making U233 will find the neutron economy is such that they simply have to load all that U233 right back into the reactor or the thing will shut down.
U-232 is also produced in LFTR reactors, and is HELLACIOUSLY radioactive. You can't work around U-232 with just a glove-box - you're gonna get a tan that way. It also poisons the reaction of a U-233 bomb, so you've got to separate it out, so you're back to centrifuges and the like, and you're gonna have to throw out the contaminated and radioactive centrifuges when you're done as well.
Meldroc, Waster of Electrons
In this case, Dr. No is Ian Betteridge, who coined Betteridge's Law (though obviously the idea has been around long before him).
Still talking about large centralised power plants, are we?
I'll put my money behind decentralised power. In fact, I already have ... 3.5kw PV system just installed on the roof.
Cogeneration units for at-home are also gaining popularity, particularly in Germany and Spain. Whispergen.
Do not mock my vision of impractical footwear
You have a very caustic liquid at hundreds of degrees which is infused with very large amounts of high level radioactive waste. Fission daughter products which in a regular reactor are solid and encased in zirconium steel and treated with utmost care are now free floating in something very hot, flowing and caustic. What if if there's an accident and it rains. Or a flood. The fission products are very water soluble.
Every power plant also has to be a very nasty chemical separation and reprocessing plant. Consider the contamination just in "normal" operation. And consider the people running them.
What happens if it cools off and solidifies? You've frozen radioactive waste in the pipes a multi-billion dollar plant, and you can't go in there for decades.
There aren't some failure modes of existing reactors, but there are other failure modes and problems.
It might be a good idea to have one or two, very highly regulated and operated with the utmost skill (i.e. not for profit) used to burn up actinides wastes from other reactors.
kill me dead..... erm...isn't "it will kill you" enough? the added "you dead" seems utterly extraneous
Greetings Pedant!
Welcome to Slashdot. You will fit in here quite nicely!
Enjoy your prolonged stay.
Coal power has rendered a good sized area including a whole town uninhabitable for the foreseeable future. A fire started in a coal seam and just won't go out. The CO levels in the town range from harmful to deadly depending on the wind at the time. Eventually, it will all fall into a sinkhole and burn.