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THORIUM. Is it really that safe and great alternative to Nuclear? Is it the Other Miracle that Bill Gates is looking for?

I've been against Nuclear all my thinking life.. so from about age 20 and am now 54. Japan has not helped me become a lover of Nuclear. One thing that I heard briefly in a news report, was the word Thorium. It is apparently a rare earth mineral that is found with Uranium and dug at the same time.
I read the following.. and are yet to check the facts...
* It is a very efficient source of power generating material.
* It has already been dug up and is sitting in piles
* If there is a problem, you just simply turn it off like a light
* The waste can not be used to make a bomb
* Current Nuclear plants can be converted to use it
* It's actually cheaper than Uranium
* It doesn't require those big exclusion zones

Personally, I don't know enough about it, but from what I've read in an article titled "A report on Thorium: The newest of the technology metals . by Jack Lifton" which certainly seemed comprehensive and informed, I'm starting to wonder why this conversation hasn't been had before.

Interestingly, I don't see any reference to Thorium on the Terrapower website even though Stewart Brand referenced it in his Debate FOR Nuclear Power at about the 7 minute mark in the debate. I do note that a search for Thorium on the Terrapower website gives no hits at all.. Refer 13:20 into the Bill Gates speech as well. Not sure why.

What do YOU think?

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    Mar 16 2011: Just to make one thing clear at first:

    Thorium power is nuclear power.

    The main point of using thorium, in addition to the proliferation issues with uranium, is that there is 10 fold amount of it available compared to Uranium. If you take into account also the fact that we only use uranium-235 in our nuclear reactors, and this consitutes only 0.7% of the total amount of uranium, the increase is 100 fold.

    Thorium reactors also operate by burning uranium. This is created from thorium by bombarding it with neutrons. This forms uranium 232, which is highly radioactive and is hence hard to deal. This is why U232 can't be used for nuclear weapons, it's hard to handle.

    If you consider the events which are now unfolding in Japan, the heat being released at Fukushima is from the fission products. Fission products are an inevitable result of fission processes and therefore such an event could also happen to a thorium nuclear power plant.

    Thorium as a nuclear fuel is propably the way to go in the future. This is due to it's high availability and low price. But before we get there we need to learn a lot more about large breeder reactors and reactors operating on fast neutrons.
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      May 14 2011: No, the main point of Thorium is not it's greater abundance or where it's cheaper. IV generation uranium reactors would greatly extend the uranium resources making it last many many times longer than the current practices would allow.

      The main point of Thorium is that it is ideal for use in a liquid fuel reactors. Liquid fuel reactors have several huge advantages in terms of efficiency and safety. Efficiency because the you can easily burn the fuel to near 100% rather than only about 1% for one pass of Uranium solid fuel. Safety because the liquid salts are self-quenching, you heat them up they expand and you lose criticality necessary to maintain fission reaction, also you lose power and the solid frozen salt plug melts allowing the core to drain by gravity into a tank that maximizes passive heat dissipation. No need for diesel power generators to cool the core on shutdown means the problem that occurred in Japan would not have happened with thorium liquid fuel reactors. These liquid salt reactors operate at atmospheric pressure without high pressure water and can be gas cooled, Energy generation is more efficient gas turbines.

      So no, the events as happened in Japan with the melting of solid fuel would not have happened with liquid fuel. The explosive expansion of high pressure water into steam or the creation of Hydrogen gas from the zirconium cladding of the solid fuel would not have happened either.

      Thermal breeder reactors are much more inherently safe than fast breeders, and you can also build much small more compact reactors too. Bigger isn't necessary.
      • May 17 2011: I have been tryiing to locate some more specifics on MSR Thorium reactors. Thanks very much..Do I understand you correctly to say that such a reactor would be "failsafe" , or self-extinguishing (without positive human inputs) in the worst case scenario? If so, why aren't they all like that?! They might even be able to get Insurance...Rumor has it that the real reason is that the process doesn't produce weapons grade Uranium for bombs. What do you think of thiat idea?
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          Jul 7 2011: Yes,
          a well-designed Liquid Fluoride Thorium Reactor would shutdown on it's own with no humans if the power went out.

          If you tried to over-heat it you would just end expanding the liquid salt volume (the liquid is not pressurized and has a similar viscosity to water) & it there would be less fuel in the core of the reactor reducing fission causing the reactor to essentially shut off and start to cool.

          Nuclear engineers during World War II had three choices to make fission bombs. One through Uranium, one through Plutonium, and one through Thorium. Two of those three choices had more direct solutions. The last one through Thorium required too many steps and some big technical drawbacks. They chose to work with making Uranium (Little Boy) and Plutonium (Trinity and Fat Man) bombs. After the war, the experience with nuclear reactors used to make bomb material (Hanford) was used to make power plants for Navy ships and submarines. The first civilian reactors were basically Navy designs place on land. Only the nuclear plane idea being worked on at the Oak Ridge National Laboratory in the 50's and 60's and funded by the Air Force put such constraints on the designs (safety, compactness, no high pressure, no need for water, higher efficiency of fuel, no need to replace fuel because of Xenon desturction, etc.) that liquid reactors (molten salts) using Thorium which is usable in the thermal part of the spectrum became seen as a necessity. The lead scientist on the project was the same scientist who invented the light water reactors that the Navy was using. He though that use of liquids and thorium for civilian use was by far the better way. During the Nixon Administration, his voice become politically isolated. All the expertise in liquid reactors was at Oak Ridge NL where he was in charge. Other national labs and those in the administration favored solid fuel, fast breeder plutonium reactors. He was fired. Liquid reactor project lost it's funding.
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          Jul 7 2011: the irony. is that several years later, the Carter administration canned the Fast Breeder Plutonium reactor program. That ended the U.S.'s research into any kind of breeder reactor (plutonium faster breeder solid fuel reactors now used by the French, and the safer thorium thermal breeder liquid fuel reactors which are now gaining a new look in the last few years). Breeder reactors become synonymous in the U.S. with proliferation risks even though because people talked about faster plutonium breeder designs as if that was the only type of breeder. All institutional memory of the Thorium thermal breeder program was lost by late 70's and early 80's, and in the era before the Internet, the work became just books on the shelf in the library of the national labs. So much so that you could get a Ph.D. in Nuclear Engineering and NEVER learn about Thorium as a nuclear fuel.

          So problem is now while all the work was documented and because of the internet much of it is now online for people to discover, all the engineers and experts that worked on liquid reactors from the 50's through the early 70's in the U.S. are either dead or long retired.

          So in the information age. U.S. has no jump on anyone that decides to pick up the ball and run with it. Like for example China.

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