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Power Science

Thorium, the Next Nuclear Fuel? 710

mrshermanoaks writes "When the choices for developing nuclear energy were being made, we went with uranium because it had the byproduct of producing plutonium that could be weaponized. But thorium is safer and easier to work with, and may cause a lot fewer headaches. 'It's abundant — the US has at least 175,000 tons of the stuff — and doesn't require costly processing. It is also extraordinarily efficient as a nuclear fuel. As it decays in a reactor core, its byproducts produce more neutrons per collision than conventional fuel. The more neutrons per collision, the more energy generated, the less total fuel consumed, and the less radioactive nastiness left behind. Even better, Weinberg realized that you could use thorium in an entirely new kind of reactor, one that would have zero risk of meltdown. The design is based on the lab's finding that thorium dissolves in hot liquid fluoride salts. This fission soup is poured into tubes in the core of the reactor, where the nuclear chain reaction — the billiard balls colliding — happens. The system makes the reactor self-regulating: When the soup gets too hot it expands and flows out of the tubes — slowing fission and eliminating the possibility of another Chernobyl. Any actinide can work in this method, but thorium is particularly well suited because it is so efficient at the high temperatures at which fission occurs in the soup.' So why are we not building these reactors?"
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Thorium, the Next Nuclear Fuel?

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  • Re:Cost (Score:2, Informative)

    by RichMan ( 8097 ) on Saturday January 02, 2010 @12:08PM (#30622882)

    Nope the thorium reaction path produces weapons grade fissibles.
    So still no explanation as to why no common use of Thorium reactors. []

    The thorium fuel cycle mainly creates Uranium-233 which can be used for making nuclear weapons, and since there are no neutrons from spontaneous fission of U-233, U-233 can be used easily in a gun-type nuclear bomb. ... some weapons proliferation risk due to production of 233U; ....

  • Re:Cost (Score:5, Informative)

    by Anonymous Coward on Saturday January 02, 2010 @12:08PM (#30622886)
    India's Kakrapar-1 reactor is the world's first reactor which uses thorium rather than depleted uranium to achieve power flattening across the reactor core.[21] India, which has about 25% of the world's thorium reserves, is developing a 300 MW prototype of a thorium-based Advanced Heavy Water Reactor (AHWR). The prototype is expected to be fully operational by 2011, following which five more reactors will be constructed.[22] Considered to be a global leader in thorium-based fuel, India's new thorium reactor is a fast-breeder reactor and uses a plutonium core rather than an accelerator to produce neutrons. As accelerator-based systems can operate at sub-criticality they could be developed too, but that would require more research.[23] India currently envisages meeting 30% of its electricity demand through thorium-based reactors by 2050.[24]
  • by Greg Hullender ( 621024 ) on Saturday January 02, 2010 @12:24PM (#30623070) Homepage Journal
    There's no question that Thorium has lots of advantages over Uranium, but it's much harder to make it work at all. Check out the list of disadvantages in the Wikipedia article "Thorium fuel cycle." It adds all kinds of engineering challenges that Uranium doesn't have.

    Of course, if we're going to tackle the problems of the 21st Century, we have to be willing to solve hard engineering problems, but it makes perfect sense to tackle the easier ones first. Especially when it takes years to build and test a reactor, so developing anything really new is apt to take a decade or two before it can actually make money. So far, it has always seemed easier to tweak the existing, mature Uranium technology to deal with its remaining problems.

    Personally, I'd love to see a sustained government effort to develop commercially viable Thorium power plants. (I have thought this since the 1970s.) But the reason that hasn't happened yet is Thorium just has too many unsolved problems -- it's not because of some industry conspiracy.


  • Re:20+ years (Score:2, Informative)

    by Bigjeff5 ( 1143585 ) on Saturday January 02, 2010 @12:26PM (#30623084)

    India has Thorium reactors today.

  • by Anonymous Coward on Saturday January 02, 2010 @12:31PM (#30623146)

    "You sure it isn't because their oil production has peaked and is now declining alarmingly quickly?"

    Yes. I'm pretty sure... I've seen the actual raw data on oil reserves for that region while consulting in the Middle East. They're not peaking for another 200 years or so at the projected outputs.

    They've all read the peak oil books and are laughing all the way to the bank.

    (posting anonymously for obvious reasons)

  • by ameline ( 771895 ) <ian,ameline&gmail,com> on Saturday January 02, 2010 @12:35PM (#30623176) Homepage Journal

    As the subject says, there is already a proven and safe reactor design that can use the thorium fuel cycle.


  • by FooAtWFU ( 699187 ) on Saturday January 02, 2010 @12:35PM (#30623178) Homepage
    That's probably a point, but with the fervor of their anti-Israeli rhetoric, only a fool would ignore the possibility that they're after a nuclear weapon.
  • by Anonymous Coward on Saturday January 02, 2010 @12:37PM (#30623214)

    36 comments so far, and only one mentioning the #1 problem of current nuclear technology: WASTE.

    The problem is still unsolved but nobody cares about it. Meanwhile, we are cumulating tons of material which will be dangerously radioactive for many generations after ours.

    If switching to thorium stops the generation of highly radioactive waste, we have the #1 good reason for doing so.

  • Re:Why not? (Score:5, Informative)

    by QuoteMstr ( 55051 ) <> on Saturday January 02, 2010 @12:48PM (#30623318)

    yes, U is getting in short supply now

    Not true [].

  • Re:Because... (Score:2, Informative)

    by Bigjeff5 ( 1143585 ) on Saturday January 02, 2010 @12:52PM (#30623360)

    You know India uses thorium reactors, right?

    Somebody must not have told them how impossible it was, or how many years it would take, or how it wasn't cost effective.

    Stupid Indians (with a dot, not feathers).

  • Re:Gimmick (Score:5, Informative)

    by naasking ( 94116 ) <> on Saturday January 02, 2010 @01:16PM (#30623666) Homepage

    Thorium is a significant efficiency improvement over Uranium or Plutonium reactors, and this is disregarding the safety improvements inherent to a salt-based reactor. I'm not sure how you could possibly conclude it's a minor improvement.

  • by careysub ( 976506 ) on Saturday January 02, 2010 @01:20PM (#30623708)
    The Wired Magazine article presents a false picture of the development of nuclear power and leaves out some crucial facts about thorium reactors. A key fact about thorium reactors mentioned no where in the article: you can't build a reactor, load it with thorium alone, and have it work. It will sit there producing no power forever. This because thorium is only the breeding material and is not fissile. To get the reactor to produce power the thorium has to be mixed with plutonium or U-233 bred in some uranium fueled reactor somewhere, or with highly enriched U-235. In other words - the reactor has to be loaded with bomb-usable material and there has to be a lot of it, enough for hundreds of weapons.

    This is part of why the whole quasi-conspiratorial story of "why we didn't go with thorium in the first place" is utter nonsense. It was not because "we wanted bombs instead" and were prejudiced against "superior thorium", it is because only if you have an established nuclear industry cranking out materials usable in bombs by the thousands can you build these reactors in the first place. Either you must have natural/low enriched uranium reactors to produce plutonium, or you need large amounts of highly enriched uranium (prime bomb material) to load into thorium breeders.

    Also unacknowledged is that the particular type of reactor being promoted, the molten fluoride salt reactor, was and is a complex technology that requires substantial additional development. Only one single reactor of this kind was ever built, and it was an 8 megawatt (thermal) materials test reactor, not a power reactor. We are looking at many years of additional development before construction can start on a prototype full scale power reactor. I agree that this technology should be further pursued, and it may turn out more successful that plutonium breeders (no successful power plants have been built, just several failures) but it is by no means guaranteed.

    Hyman Rickover, by the way, was interested in light water uranium fueled reactors because they are a good technology for powering submarines, not because they produce plutonium (they are lousy plutonium producers, the yield is low and the material produced has terrible properties for bombs).

    Check out the 2005 IAEA survey document ( for a good summary of the thorium technology options and prospects.

  • Re:Because... (Score:3, Informative)

    by Vellmont ( 569020 ) on Saturday January 02, 2010 @01:25PM (#30623772) Homepage

    That's a lot of claims. Do you have any cites for any of them?

    The article say thorium does NOT have to be enriched. A quick look at the the isotopes of thorium [] wikipedia article confirms that Th-232 is the only isotope of any real abundance. That's a bit of a major error on your part, and casts doubt on the reliability of the rest of your post.

  • Re:Because... (Score:5, Informative)

    by naasking ( 94116 ) <> on Saturday January 02, 2010 @01:29PM (#30623814) Homepage

    By most accounts, a functional prototype reactor is 20 years away.

    The designer of the molten salt Thorium reactors ran his reactor non-stop for over 10 years IIRC. This was in the 1960s. What is unproven exactly?

    Extracting thorium from the ground is harder than for uranium,

    Which we will run out of in 10 years [].

    Thorium will also produce dangerous, radioactive by products,

    And Uranium produces candy canes and puppies? If Thorium really is harder to refine or weaponize than Uranium, we'd be better off switching to Thorium, so you contradict yourself.

    Also, Thorium reactions do not produce plutonium. The fact that Thorium reactions do not produce weaponized by products is one of its huge advantages, above and beyond its abundance and higher efficiency as nuclear fuel when compared to Uranium.

  • Re:zero-risk? (Score:1, Informative)

    by Anonymous Coward on Saturday January 02, 2010 @01:46PM (#30624016)

    Actually there is. There is genuinely foolproof and can't fail. The reason is physics would have to be changed for them to fail. But then I guess you worry about that too?

  • by Cheech Wizard ( 698728 ) on Saturday January 02, 2010 @01:52PM (#30624094) Homepage

    "You sure it isn't because their oil production has peaked and is now declining alarmingly quickly?"

    Yes. I'm pretty sure... I've seen the actual raw data on oil reserves for that region while consulting in the Middle East. They're not peaking for another 200 years or so at the projected outputs.

    They've all read the peak oil books and are laughing all the way to the bank.

    (posting anonymously for obvious reasons)

    Posting anonymously because it's bull. 200 years to peak oil there? Maybe if they don't sell any.

  • by Anonymous Coward on Saturday January 02, 2010 @01:59PM (#30624188)

    Buffoonery. It's business, pure and simple.

    We have an established process and no one wants to buy that system. There is no reason to build a new system, which will still generate wastes which no one wants in their back yard, and small amounts of weapons grade material which no one wants, and basically no energy producer is willing to fund for fear that they will be betting their entire company on a system that will be hindered.

    Progress-energy and others have spent a ton of money only to be held up by regulators (NRC) for 24 months! Figure the vig on a 5 Billion dollar loan for 24 months! This hold-up is PARTIALLY because of the political fear that nuclear is BAD. These power producers are borrowing BILLIONS of dollars and paying INTEREST every day on these dollars to build a very long term system, only to be held up by all manner of interests (Federal, State, and local).

    You want nuclear of any kind? You need to guarantee some loans. Nuclear simply isn't politically correct. Period.

    Simply put, it MAY BE the safest power system that the planet has to offer, and no one wants it because it is "nuclear". NIMBY. Average Joe doesn't want it. Period.

    It won't matter if it is plutonium, uranium, thorium, pebble bed, liquid fuel, gaseous fuel, or run by fairy dust! People are scared of nuclear, and it will take a ton of long term education the change that. "A person is smart. People are dumb, panicky dangerous animals and you know it. "

    And by the way, I know a couple of aspiring nuclear engineers who would love to work on thorium reactors, but there are no jobs in nuclear right this second. Hiring freezes abound. Also, you can build a perfectly good bomb from Thorium by-products. U-233 Teapot MET 1957 20+kt bomb anyone? And you can build a perfectly safe reactor from highly enriched U-235. Or plutonium. Finally, you can build a suitable explosive device from your water heater! Go watch Mythbusters and scale up according to need.

    Pedal your conspiracies elsewhere.

    Your humble senior reactor operator.

  • Re:Because... (Score:5, Informative)

    by naasking ( 94116 ) <> on Saturday January 02, 2010 @02:01PM (#30624216) Homepage

    The U-233 generated in a Thorium reactor is consumed in the Thorium reaction itself to sustain the reaction []. It would take significant effort to extract it in a usable form. The proliferation danger is significantly lower when compared to our existing nuclear infrastructure.

  • Re:Because... (Score:3, Informative)

    by ee2go ( 917739 ) on Saturday January 02, 2010 @02:02PM (#30624220)
    Not quite. The current Indian reactors use Thorium instead of depleted Uranium to even the core temperature. Even the next generation AHWR reactor will only use Thorium as part of the fuel (from here: []):

    In India, construction is expected to start early in the next decade on the first 300 MW(e) advanced heavy water reactor, which has been developed for co-generation applications. The reactor is designed to operate with 233U-Pu-Th fuel; it uses boiling light water as a coolant and heavy water as the moderator.

  • by AigariusDebian ( 721386 ) <aigarius&debian,org> on Saturday January 02, 2010 @02:06PM (#30624258) Homepage

    Well, just load it up with some waste from the current reactors. Poison it with U-238 so that it is too noisy to use in any nuclear weapon and off you go, it is self-sustainable from that point and does not need any more Uranium.

  • by ThePhilips ( 752041 ) on Saturday January 02, 2010 @03:01PM (#30624786) Homepage Journal

    Posting anonymously because it's bull. 200 years to peak oil there? Maybe if they don't sell any.

    IIRC, there is an embargo on Iran selling oil. In other words: yes, they do not sell any.

  • Re:zero-risk? (Score:3, Informative)

    by electrosoccertux ( 874415 ) on Saturday January 02, 2010 @04:05PM (#30625472)

    It's called a pebble-bed reactor, and the reaction is automatically limited in the mixture of uranium as the reactor heats up through a mechanism called neutron cross section broadening.
    It is failproof.

  • by Buelldozer ( 713671 ) on Saturday January 02, 2010 @06:18PM (#30626758)

    How can you say these things with a clear conscience? You're either misinformed or attempting to pull off one helluva a bald faced lie!

    "Last I checked Iranians weren't training terrorists." [] - London, Feb. 27 – Iran Focus has obtained a list of 20 terrorist camps and centres run by Iran’s Islamic Revolutionary Guards Corps (IRGC).

    "And it is well known that Iran has actually not supported Hezbollah, contrary to popular American rhetoric."

    Oh really? [] - "The Hezbollah, or Party of God, (also HizbAllah or Hizbullah) is an Iranian movement formed at the time of the Iranian Revolution to assist the Ayatollah Ruhollah Khomeini and his forces in consolidating power."

    Or [] - "On Tuesday, Iran's rhetorical threats against Israel and its unswerving embrace of Hezbollah continued."

    I'm trying to not be offensive but your viewpoint has left me incredulous! How do you say the things you do, which are in direct contradiction to well known and cited information, WITHOUT CITATION and then get modded to +5 insightful?

    Help me out here.

  • Re:Why not? (Score:5, Informative)

    by definate ( 876684 ) on Saturday January 02, 2010 @07:04PM (#30627156)

    "It is clear from this Figure that known uranium resources have increased threefold since 1975, in line with expenditure on uranium exploration. (The decrease in the decade 1983-93 is due to some countries tightening their criteria for reporting. If this were carried back two decades, the lines would fit even more closely.) Increased exploration expenditure in the future is likely to result in a corresponding increase in known resources."

    "Widespread use of the fast breeder reactor could increase the utilisation of uranium 50-fold or more. This type of reactor can be started up on plutonium derived from conventional reactors and operated in closed circuit with its reprocessing plant. Such a reactor, supplied with natural or depleted uranium for its "fertile blanket", can be operated so that each tonne of ore yields 60 times more energy than in a conventional reactor."

    Read more, type less.

  • by sentientbeing ( 688713 ) on Saturday January 02, 2010 @07:47PM (#30627548)
    You dont seriously believe we spent billions invading Iraq to bring democracy to the Middle East?

    Go and watch The History of Oil - Robert Newman. Its both hilarious and informative. []
  • Re:Why? (Score:5, Informative)

    by JetTredmont ( 886910 ) on Saturday January 02, 2010 @09:01PM (#30628130) Homepage

    The "uses more carbon to produce than it saves in its lifetime" charge is a persistent myth. It seems just "shocking" enough to be true, and happens to coincide with what many rich interests would like to be true. As a result, it comes up quite often in non-fact-centric talk shows and as a result is something that a lot of people just "know". Unfortunately, it's just not true.

    I have researched this and haven't been able to find a time when it was EVER true, but it certainly isn't true of either modern solar cells (even in small-scale deployments) or wind turbines. Moreover, as the general power supply becomes "greener", the carbon footprint for manufacturing (a huge portion of which comes from the energy needed to produce, not raw materials) also declines.

    Example calculation for mid-size (office building) solar deployment: []

    - Calculates a carbon break-even point of 15 months, for a product expected to last for 25 years on the inside.
    - Obviously comes from the company making these, so take it with a grain of salt, but it's not likely to be off by the order of magnitude or more needed to make your statement true.

    I can't find similar calculations for wind turbines fro a quick Google search, but the return on carbon "investment" there is shorter-term (assuming a windy area and fairly large-scale deployment of multiple wind turbines in a pass). If you have a citable reference stating otherwise, please share it with the class.

  • Re:zero-risk? (Score:3, Informative)

    by Rising Ape ( 1620461 ) on Saturday January 02, 2010 @11:00PM (#30628760)

    Radioactivity is a concentration problem. Radioactivity, just like chemical pollution, is dangerous only beyond a certain threshold: we are right now exposed to cosmic rays, but that is not a cause of cancer, because our bodies can handle that level of radioactivity: they evolved for millions of years in this environment.

    That's not the generally accepted view, which is that any dose of radiation could cause cancer, with probability proportional to dose (up to a point). Your "dangerous beyond a threshold" argument is only true for the acute effects of radiation, not its carcinogenic characteristics. If the standard model is correct, the radiation from coal plants certainly does cause cancer (as do cosmic rays), it's just hard to detect because cancer is so common anyway.

As of next Tuesday, C will be flushed in favor of COBOL. Please update your programs.