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Power Science

Thorium, the Next Nuclear Fuel? 710

Posted by Soulskill
from the plenty-on-the-auction-house dept.
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?"

Thorium, the Next Nuclear Fuel?

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  • Why? (Score:5, Insightful)

    by Broken scope (973885) on Saturday January 02, 2010 @11:02AM (#30622798) Homepage

    Because a number of groups with rather different goals have one thing in common.

    Sustainable nuclear power is a threat to their pocketbooks.

    • Re: (Score:3, Insightful)

      by Ichijo (607641)

      Sustainable nuclear power is... oxymoron. There's only so much Thorium in the world.

      • Re:Why? (Score:5, Insightful)

        by QuoteMstr (55051) <> on Saturday January 02, 2010 @12:13PM (#30623634)

        Hey! Guess what? Everything is finite. What do you think you build solar panels and wind turbines from, pot smoke?

      • Re: (Score:3, Interesting)

        by cheesybagel (670288)
        There's only so much coal in the world as well. But we have been burning it for centuries and there is still more.

        There's only so much carbon fibre in the world to make windmills too.

      • Re: (Score:3, Interesting)

        by Dr. Spork (142693)

        Sorry to break it to you, but there are only so many years that the sun will be burning and the wind will be blowing. So these aren't sustainable either, right? The truth is, there is a practical method for extracting Uranium and Thorium from sea water. Japanese research shows we could do this for about $120/kg of Uranium - which, if burned completely in a reactor produces a great deal of energy. Since Thorium is more abundant, it should be cheaper.

        And the nice thing is that even if we used seawater Urani

  • Why not? (Score:5, Insightful)

    by Enry (630) <enry&wayga,net> on Saturday January 02, 2010 @11:07AM (#30622878) Journal

    - 1/2 the country doesn't believe what scientists tell them: evolution, global warming, birth control/STDs. Why believe them now?

    - No new nuclear plants have been built in 30-ish years.

    - uranium was thought to be pretty much endless, so why do more research into thorium? (yes, U is getting in short supply now)

    - nuclear power still has the stigma of 3 Mile Island and Chernobyl attached to it. It'll be tough to get public opinion on that changed, especially with advances in fuel cell and solar technologies

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

      by QuoteMstr (55051) <> on Saturday January 02, 2010 @11:48AM (#30623318)

      yes, U is getting in short supply now

      Not true [].

  • Gimmick (Score:5, Insightful)

    by QuoteMstr (55051) <> on Saturday January 02, 2010 @11:08AM (#30622894)

    On the one hand, modern uranium reactors (pebble bed, or even well-made light water reactors) are perfectly safe. Using thorium instead is at best a minor improvement.

    On the other hand, if using a different fuel convinces members of the general public that nuclear power is safe, and allows the construction of new facilities in less than a decade, that's great, and worth it even if thorium is slightly inferior as a fuel. In short, it can be a PR win.

    • Re:Gimmick (Score:5, Insightful)

      by Rehnberg (1618505) on Saturday January 02, 2010 @11:19AM (#30623018)


      Based on the article, I'm not sure that thorium is an inferior fuel. At the very least, it seems more efficient and more abundant, as well as less dangerous than uranium. To me, that's more important than raw power output, especially given that thorium cannot be weaponized.

    • Re:Gimmick (Score:5, Informative)

      by naasking (94116) <naasking@gmail. c o m> on Saturday January 02, 2010 @12:16PM (#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.

  • Problems (Score:5, Interesting)

    by SteveAstro (209000) on Saturday January 02, 2010 @11:13AM (#30622954)

    I am working on the very periphery of the problem, designing equipment to measure the properties of hot radioactive molten fluorides - in the region between 900-1700 C, for European nuclear researchers. Clearly one of the problems which should be obvious is that we are looking at cutting edge material technology to work at these temperatures and neutron fluxes !

    • Re:Problems (Score:5, Funny)

      by DoofusOfDeath (636671) on Saturday January 02, 2010 @11:28AM (#30623106)


      Well, duh. We didn't mention it because it was so obvious! Most slashdotters have known that crap from, like, CS 201.

  • Why move to Thorium? (Score:3, Interesting)

    by kestasjk (933987) * on Saturday January 02, 2010 @11:15AM (#30622984) Homepage
    Uranium is also abundant and safe, but it's a lot better known than thorium. Thorium is promising, but there's no need for an alternative nuclear fuel at the moment (and probably won't be for a very long time). The nuclear fuel isn't what caused the Chernobyl disaster, it was the reactor, and huge amounts of research has been invested into new uranium based reactors with all sorts of properties making them safer and cheaper.

    Thorium looks good and should be researched, but with nuclear fuel we're spoiled for choice. The idea that we need to find a new nuclear fuel for safety or cost reasons only damages the chance of people getting behind the fine technology we have/are-developing now.
    • Re: (Score:3, Interesting)

      by naasking (94116)

      Because we're scheduled to run out of easily mined Uranium within the next 10 years [], unless the US's military stockpiles are released. Thorium is far more abundant, is safer since it can't be weaponized and it's meltdown-proof in liquid salt reactors, and more importantly, is much, much more efficient as a nuclear fuel. So I disagree with all of your points, save one: Uranium is not abundant or safe, but I grant you that Uranium is more well known; it's infamy can also be considered a problem however.

  • by wembley fraggle (78346) on Saturday January 02, 2010 @11:15AM (#30622986) Homepage

    These days, people only mine Thorium while they're working on getting their skill up to the Fel Iron and outlands level. One thing worth noting is that somewhere in the past few patches, they've made it so you can mine Fel Iron at 275, which is pretty nice. No more running around the Eastern Plaguelands looking for Rich Thorium Nodes for those last few points when you'd rather be in Hellfire Peninsula.

  • by Rehnberg (1618505) on Saturday January 02, 2010 @11:17AM (#30623006)
    I brought this article up in my government class a few weeks ago (we spend more time discussing what the government is doing than how it's set up), and I couldn't convince a single person that this new kind of reactor was safe. Let's face it: years of not building reactors combined with years of scare tactics from our government about other countries building reactors can't be undone with science. Propaganda > Science
    • Re: (Score:3, Insightful)

      by nadaou (535365)

      Propaganda > Science

      yeah, but science has a much longer half-life.

  • Because... (Score:4, Interesting)

    by perrin (891) on Saturday January 02, 2010 @11:23AM (#30623062)

    The debate has been ranging here in Norway lately, since we hold a lot of the world's known reserves of the stuff (as opposed to many wild guesswork assumptions about possible reserves around the world). The reason why not more reactors are built is quite simply because the technology is not there yet. By most accounts, a functional prototype reactor is 20 years away. It is a very complicated technology, and more difficult to engineer safely than uranium reactors that we currently know a lot about. Several studies, for instance from MIT, cast doubt on whether thorium reactors will even be cost effective. Extracting thorium from the ground is harder than for uranium, and the enrichment process is more difficult and costly. Thorium will also produce dangerous, radioactive by products, and if you have enrichment capabilities for thorium, it is not a far step further to produce weaponized plutonium.

    So it may be the future, but apparently no silver bullet.

    All this is IANANP (I Am Not a Nuclear Physicist) so I guess someone reading ./ can answer this better than me.

    • Re: (Score:3, Informative)

      by Vellmont (569020)

      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) <naasking@gmail. c o m> on Saturday January 02, 2010 @12:29PM (#30623814) Homepage


      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.

  • by dfay (75405) on Saturday January 02, 2010 @11:24AM (#30623068)

    According to this [] (see the section called "Fuel cycle concerns"), because there is no need to refine the Thorium fuel, which is the stage where the nuclear power companies currently make their money, they would need to change their business model to cope. We all know how much companies like to do that.

    So, you combine the politicians' lack of desire to risk being associated with nuclear power, and the entrenched industry's lack of interest in the business model, and it's suddenly easy to explain.

  • by Greg Hullender (621024) on Saturday January 02, 2010 @11:24AM (#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.


  • by ameline (771895) <ian.ameline@g m a> on Saturday January 02, 2010 @11:35AM (#30623176) Homepage Journal

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


  • by prefec2 (875483) on Saturday January 02, 2010 @11:49AM (#30623330)

    Such reactors may be less dangerous and the may produce less radioactive waste. But even though. They still produce radioactive waste, which we cannot handle. And it uses still a extremely limited resource. We will eat up the reserves in no time. And it would be again a centralized energy production. We want a decentralized energy production to become independent from big energy companies and to produce the energy more safely. And a large number of small generators are much less vulnerable to a total loss than one big one. Big technology is bad technology.

    • by QuoteMstr (55051) <> on Saturday January 02, 2010 @12:10PM (#30623580)


      Without realizing it, you've stuck upon the real psychological motivation behind the "decentralized everything" movement: it's political. It's a reflective reaction against the complexity of modern society, and against globalization.

      Every honest intellectual person knows that sometimes centralization is desirable. Centralization is cheaper, more efficient, and often cleaner and safer as well. It's a lot cheaper for one building on campus to generate steam than for shack to have its own heater. It's easier to scrub the output of 100 coal plants than that of 10,000 automobiles.

      Yet there are otherwise-intelligent people arguing for community-run, small, decentralized infrastructure even where it's batshit insane, like for nuclear power plants. This is not the product of honest reasoning, but an expression to live out the fantasy of living in a commune in the woods.

      You want to stem the power of large corporations? I'm with you. Regulate them. But sometimes scaling up an operation is a no-brainer.

      The attitude that small is always beautiful is the product of a small mind.

      • Centralization is to some extent the direct result of specialization within society. Nuclear power is extremely complex and to work in it, one needs highly specialized training. The direct result is that only a small subset of the population will ever be able to build and operate nuclear power plants, and thus nuclear power generation will always be highly centralized. The same is true of coal power or natural gas power generation, or, for that matter, food and clothing production. The less time I spend man

  • Why? (Score:3, Interesting)

    by arthurpaliden (939626) on Saturday January 02, 2010 @11:57AM (#30623416)
    Because 'Big-Uranium' bought up all the patents and made them secret. ...... Just like 'Big-Oil" bought up the super-dooper battery patents.
  • by careysub (976506) on Saturday January 02, 2010 @12:20PM (#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: (Score:3, Informative)

      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 SD-Arcadia (1146999) on Saturday January 02, 2010 @03:30PM (#30625730) Homepage
    I suggest anyone seriously interested in our energy future to take the time to go through this report called "Technofixes" by CorporateWatch UK []
    According to this report, only wind and solar come out as having the potential to be both socially desirable and effective in combatting climate change. Hypothetical 4th generation nuclear reactors, even if decided upon, would be too little too late because it takes long to deploy at great up-front cost, and the waste problems remain unsolved (despite what you may hear about the magic of breeder reactors etc.)

Sentient plasmoids are a gas.