Reddit reviews THORIUM: energy cheaper than coal

OOD115

>I've railed against Thorium reactors for years on here, so much so that I'm so fucking tired of talking about it. I worked on nuclear plants as an engineer for a decade, but am no longer involved.

>Thorium reactors don't even solve any proliferation concerns. I see so many people saying it should be exported to third world countries because they can't use it to make a bomb. This is fucking false. Th-232 is fertile and can create U-233 after neutron capture, which is fissile. This can be chemically separated out to form weapons-grade U-233.

>It solves fucking nothing. It's propaganda from "Gen IV" universities looking for funding for projects that will never get built. And it's being pushed by India because they have enormous Thorium reserves, but no Uranium resources.

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LFTRs produce Uranium 233 which is indeed a weapons grade material, however it is poisoned with Uranium 232 which is a proliferation prophylactic.

LFTRs are also non appreciable breeders meaning if you divert the Uranium 233 they generate to try and use it for weapons, the reactor cannot sustain itself and shuts down.

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Robert Hargraves teaches energy policy at Dartmouth an Ivy League school.

Robert Hargraves graduated from Brown University (PhD Physics 1967)

http://www.thoriumenergyalliance.com/downloads/American_Scientist_Hargraves.pdf

"The uranium-233 produced from thorium-232 is necessarily accompanied by uranium-232, a proliferation prophylactic. Uranium-232 has a relatively short half-life of 73.6 years, burning itself out by producing decay products that include strong emitters of high-energy gamma radiation. The gamma emissions are easily detectable and highly destructive to ordnance components, circuitry and especially personnel. Uranium-232 is chemically identical to and essentially inseparable from uranium-233."

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"Only a determined, well-funded effort on the scale of a national program could overcome the obstacles to illicit use of uranium-232/233 produced in a LFTR reactor. Such an effort would certainly find that it was less problematic to pursue the enrichment of natural uranium or the generation of plutonium."

"the proportion of U-232 would be about 0.13% for a commercial power reactor. A year after separation, a weapons worker one meter from a subcritical 5 kg sphere of such U-233 would receive a radiation dose of 43 mSv/hr, compared to 0.003 mSv/hr from plutonium, even less from U-235. Death becomes probable after 72 hours exposure. After ten years this radiation triples.

A resulting weapons would be highly radioactive and therefore dangerous to military workers nearby. The penetrating 2.6 MeV gamma radiation is an easily detected marker revealing the presence of such U-233, possibly even from a satellite.

For personnel safety, any U-233 material operations must be accomplished by remote handling equipment within a radioactively shielded hot cell. This can be designed to make it very hard for any insiders or outsiders to remove material from the hot cell."

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LFTRs are not designed to be appreciable breeders, they will produce only as much U233 as is required to continue their operation and no more, removing U233 from the equation means the reactor will eventually shut down.

"However, taking into account the overall fission rate per capture, capture by other nuclei and so on, a well-designed LFTR reactor should be able to direct about 1.08 neutrons per fission to thorium transmutation. This delicate poise doesn't create excess, just enough to generate fuel indefinitely. If meaningful quantities of uranium-233 are misdirected for nonpeaceful purposes, the reactor will report the diversion by winding down because of insufficient fissile product produced in the blanket."

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Thorium Energy Cheaper Than Coal - Robert Hargraves

https://www.amazon.com/THORIUM-energy-cheaper-than-coal/dp/1478161299


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Ultimately any fission reactor's neutron flux can convert U238 to Pu239 or Th232 to U233, but the best designs make that incredibly difficult and expensive.

There is no way to prevent a determined government from building a weapons program from a modified power plant. This is why they are inspected by IAEA. IAEA monitoring (or refusal thereof) makes this public knowledge.

Any government that has the resources would opt to go the proven route of U235 or Pu239, rather than have to deal with potential U232 contamination.

"I'm pretty sure the core of the people pushing thorium are just trying to rebrand good old nuclear power."

Have a look at the "SuperFuel" book that came out recently: http://books.google.com/books?id=lQm_BMnHNd0C&printsec=frontcover

Thorium is only half the story; the other is the reactor to use it, which uses molten salt both as a coolant and fuel.

You might also find http://www.amazon.com/THORIUM-energy-cheaper-than-coal/dp/1478161299 interesting.

Others include Robert Hargraves, who has a physics Ph.D. and just published a book on thorium reactors, and Ralph Moir, who published ten papers on them including one coauthored with Edward Teller. Here's an article the two published in Physics and Society, and another in American Scientist.

Another is David LeBlanc, a nuclear scientist at Carleton University. Here's his Google tech talk. And here's one by Joe Bonometti, who was a nuclear specialist at NASA.

Some others here.

Depends on which nuclear power you are talking about. There is a case to be made for Energy cheaper than coal