There is an extraordinary push by certain individuals to extol the wonders of thorium-fueled nuclear reactors. In fact, so concerted is this push that some blame me for preventing the ongoing expansion of such technology. So here are the facts about thorium for those who are interested.
The U.S. tried for 50 years to create thorium reactors, without success. Four commercial thorium reactors were constructed, all of which failed. And because of the complexity of the problems enumerated below, thorium reactors are, by an order of magnitude, more expensive than uranium-fueled reactors.
The longstanding effort to produce these reactors cost the U.S. taxpayers billions of dollars, while billions more dollars are still required to dispose of the highly toxic waste emanating from these failed trials.
The truth is that thorium is not a naturally fissionable material. It is therefore necessary to mix thorium with either enriched uranium 235 (up to 20-percent enrichment) or plutonium, both of which are innately fissionable, to get the process going. Uranium enrichment is very expensive, while the reprocessing of spent nuclear fuel from uranium-powered reactors is enormously expensive and very dangerous to the workers, who are exposed to toxic radioactive isotopes during the process. Reprocessing spent fuel requires chopping up radioactive fuel rods by remote control and dissolving them in concentrated nitric acid, from which plutonium is precipitated out by complex chemical means. Vast quantities of highly acidic, highly radioactive liquid waste then remain to be disposed of. (Only 6 kilograms of plutonium 239 can fuel a nuclear weapon, while each reactor makes 250 kilograms of plutonium per year. One millionth of a gram of plutonium is carcinogenic if inhaled.)
So there is an extraordinarily complex, dangerous and expensive preliminary process to kick-start a fission process in a thorium reactor.
When non-fissionable thorium is mixed with either fissionable plutonium or uranium 235, it captures a neutron and converts to uranium 233, which itself is fissionable. Naturally it takes some time for enough uranium 233 to accumulate to make this particular fission process spontaneously ongoing.
Later the radioactive fuel would be removed from the reactor and reprocessed to separate out the uranium 233 from the contaminating fission products, and the uranium 233 will then be mixed with more thorium, to be placed in another thorium reactor.
But uranium 233 is also a very efficient fuel for nuclear weapons: It takes about the same amount of uranium 233 as plutonium 239 — 6 kilograms — to fuel a nuclear weapon. To its disgrace, the U.S. Department of Energy has already “lost track” of 96 kilograms of uranium 233.
A total of 2 tons of uranium 233 were manufactured in the U.S., and this material naturally requires similar stringent security measures used for plutonium storage, for obvious reasons. It is estimated that it will take over $1 million per kilogram to dispose of the seriously deadly material. An Energy Department safety investigation recently found a national repository for uranium 233 in a building constructed in 1943 at the Oak Ridge National Laboratory. It was in a dreadful condition, and investigators reported that an environmental release from a large fraction of the 1,100 containers “could be expected to occur within the next five years because some of the packages are approaching 30 years of age and have not been regularly inspected.” The DOE determined that this building had “deteriorated beyond cost-effective repair and significant annual costs would be incurred to satisfy both current DOE storage standards, and to provide continued protection against potential nuclear criticality accidents or theft of the material.”
The DOE Office of Environmental Management now considers the disposal of this uranium 233 to be “an unfunded mandate.”
Thorium reactors also produce uranium 232, which decays into an extremely potent high-energy gamma emitter that can penetrate one meter of concrete, making the handling of this spent nuclear fuel extraordinarily dangerous.
Although thorium advocates say that thorium reactors produce little radioactive waste, they simply produce a spectrum of waste that’s different from those from uranium 235, which includes many dangerous alpha and beta emitters and isotopes with extremely long half-lives, including technetium 99, with a half-life of 300,000 years, and iodine 129, with a half-life of 15.7 million years.
No wonder the U.S. nuclear industry gave up on thorium reactors in the 1980s. This was an unmitigated disaster, as are many other nuclear enterprises undertaken by the nuclear priesthood and the U.S. government.
Originally published: http://www.huffingtonpost.com/helen-caldicott/thorium_b_5546137.html
10 thoughts on “Thorium”
: Advantages of LFTRs (Th fueled molten salt reactors)
No CO2 emissions. Not practical for making bombs. Breed their fuel from thorium.
Hugely efficient. Create just 1% as much waste as conventional reactors.
Do not need periodic shut downs because fission byproducts are continuously removed.
Not water-cooled, so hydrogen and steam explosions are eliminated. Well suited to arid areas and countries where water is scarce.
Don’t need huge containment domes because they operate at atmospheric pressure.
The reactor can’t “melt down” because the fuel/coolant is already liquid and the reactor vessel is designed to handle even higher temperatures.
Thorium ore is safer to mine because it is less radioactive than uranium ore.
Thorium 232 is 500 X as abundant as U-235.
Fluoride salts are easier to handle and less corrosive than the supercritical water used by solid-fuel reactors.
LFTRs are highly scalable – from small plants to 2,000 MW plants.
LFTRs could replace all of the world’s coal-powered generators by 2060.
LFTRs will cost 10-15% as much as comparable, solid fuel uranium reactors, allowing affordability to developing nations. They are suitable for modular factory production, truck transport, and on-site assembly.
LFTRs are intrinsically safe because overheating expands the fuel/salt, decreasing its density, which lowers the fission rate.
Loss of power melts a freeze plug, automatically draining the fuel into a tank to cool.
At least 99% of a LFTR’s thorium is “burned”, compared to 0.7 % of the uranium in today’s reactors.
You forgot to mention that Th 232 fission will be too cheap to meter. Thus, you may as well try to assert that Th 232 fission is sustainable; that it imposes no ecological mining scars; that it would emerge unaffected by any natural disaster; that the toxic waste it would add to the already bloated, dangerous stockpiles–is of no consequence; and that more radiation in the air, water and earth is good because its less than previous releases.
The nuclear industry owes the world a huge debt. All of its revenues and taxpayer/ ratepayer subsidies and R&D funds must now go toward the huge cost of of nuclear phase-out, clean-up and long-term safe and secure storage of nuclear waste. It seems absurd for the public to trust the nuclear industry in yet another of its nuclear ventures. We must shout out loud “No to nuclear!” We must in light of the industry record and the health and ecological hazards of fission in war, energy and economy. We must do this as intelligent, ethical beings who have an array of effective alternatives in current use, worldwide.
Wow, 50,000$ buys a dozen soulless death promoting trolls for a year.
Nuclear: millions of cancers, trillions of dollars for accidents, 5 years of proven reserves with the existing commercial tech, and materials and build time limited to 5% or less of our energy needs.
Solar, wind and wastes are nearly unlimited and cheaper.
PS, why can’t you get the chemical symbol for Thorium right?
The chemical symbol for Thorium is not displayed in this article.
Interesting conspiracy theory on thorium from a person named Caldicott who lives by conspiracy theories!
“The U.S. tried for 50 years to create thorium reactors, without success. ” – really?
How does a self-advertizing doctor claiming expertise in all things nuclear not know that the Shippingport PA reactor was reloaded with Thorium fuel in 1977 and ran until 1982, when it was scheduled for shutdown? How does Dr. Caldicott not know the result demonstrated thorium fuelling successful and that the reactor made >1% more fuel in 5 years than it consumed?
Wonder if this comment will be published. Or, will Caldicott continue to violate her Hippocratic Oath?
Call any time, Helen. I’m a Dr. too!
650 400 3071
Well, this comment has been published, although I don’t generally recommend publishing your phone number in a context like this. Up to you, I suppose.
The post you wrote for Dr. Caldicott seems to imply that the reactor which confirmed the possibility of dissolving nuclear fuel, the Molten Salt Reactor Experiment left a mess of waste behind (which it did, which could easily have been avoided), and that thorium needs to be reprocessed as a solid fuel.
You write… “Reprocessing spent fuel requires chopping up radioactive fuel rods by remote control and dissolving them in concentrated nitric acid, from which plutonium is precipitated out by complex chemical means.”
…you are clear that MSRE was a liquid fueled reactor, yes? Are you going to simultaneously complain about the MSRE mess that was left behind when research was discontinued, and also ignore the fact MSRE’s fuel was in liquid form?
This would be (principally) my beef with Dr. Helen Caldicott. Much talk about the challenge of reprocessing solid fuel. No acknowledgement that liquid fuel enables economic reprocessing, either continual or batch.
What do you personally make of this?
…I mean I’ve been investigating thorium & molten salt reactors because I’m concerned about global warming. I see attempts at addressing the problem which do not seem to be very effective (look at Germany’s CO2 progress, not their “renewable” progress, compared to France).
But Caldicott’s “prescription for survival” is crap. She’s good with burning candles for light… they emit more heat than light… you’re better off burning coal, transmitting it across the grid, and illuminating an old inefficient incandescent light bulb than burning candles to light a room.
She has said this repeatedly. And also called electric cars “cancer cars”. Repeatedly.
Ricky Onsman, what is wrong with her, and why are you helping her?
I’m not the author of this article. It was written by Dr. Caldicott (which I think you could deduce from the second sentence alone) and originally published by the Huffington Post here: http://www.huffingtonpost.com/helen-caldicott/thorium_b_5546137.html. I’ll add a credit line to the article itself shortly.
As to your questions directed at me, Gordon, first, I make of the video that it’s yet another ad hominem attack on a person who gives a shit, prepared in this case by Thorium fans who don’t. As to your second, there is nothing wrong with her that global good health, peace and safety won’t fix, and I help because it’s right.
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