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Why aren't more breeder reactors being built?

  1. Jun 26, 2011 #1
    It seems like breeder reactors are the "perfect solution" - effiecient use of fuel, higher energy returns and the ability to reduce storage time of nuclear waste from 10,000 years to 100 years.

    So why aren't more countries building breeder reactors? What problems (aside from political problems such as nuclear proliferation) are involved in the construction of this kind of reactor?

  2. jcsd
  3. Jun 26, 2011 #2
    Because the left has us brainwashed into fearing them.
  4. Jun 26, 2011 #3


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    The USA had a very good program with a very good inherently safe, proliferation resistant design known as the Integral Fast Reactor ( IFR ) developed by Argonne National Lab.
    Here's an interview about IFR with nuclear physicist Dr. Charles Till, then Associate Director of Argonne National Lab. He also discusses why it was cancelled:


    A: The arguments fundamentally were that there was no longer any need for advanced nuclear power or research on nuclear power. In President Clinton's State of the Union address that first year, one of the statements was that unneeded programs would be canceled, and for example, programs on advanced nuclear power would be canceled. So that the fundamental argument was that there was no longer any need for any further research.

  5. Jun 26, 2011 #4


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    Just because a breeder runs on / produces plutonium doesn't mean it is a proliferation risk.
    Dr. Till addresses that in his Frontline interview:


    Q: So it would be very difficult to handle for weapons, would it?

    A: It's impossible to handle for weapons, as it stands.

    It's highly radioactive. It's highly heat producing. It has all of the characteristics that make it extremely, well, make it impossible for someone to make a weapon.

  6. Jun 27, 2011 #5
    You may have just answered the question in the thread title. You can't really have it both ways -- that plutonium is too dangerous for terrorists to handle but perfectly safe for the good guys to play with.

    I think that of the major technical hurdles is that breeder reactor produce even more heat, and cannot be cooled by plain old water. The cooling media of choice seems to be liquid sodium, and since it catches fire on exposure to air you are not going to be spraying it out of a concrete pumper truck when you have a reactor problem.

    So you have a reactor with a lot more plutonium than even MOX fuel, it requires even more cooling, and the cooling media catches fire when exposed to air. Gee, what could go wrong with that scenario?

    I think you are going to have to live with the fact that these reactors are not going to happen, and it isn't because of some lefty conspiracy. Youtube pictures of exploding reactors are pretty hard to counter.
  7. Jun 27, 2011 #6
    I think the point he was going for is that to handle Pu from a breeder reactor safely you need some very specialized and expensive equipment. The average terrorist organization is not going to have enough funds to buy the equipment, and if they could it would raise some red flags.

    The reason that water is not used in breeder reactors is not because of the heat, but because it is a neutron moderator and would significantly reduce the effeteness of the reaction. Sodium is mostly transparent to fast neutrons, and will not screw up the breeder reaction.

    Yes the IFR used sodium, however that is not the only coolant available to run breeder reactors. The Russians used a lead-bismuth mix, defiantly not explosive when exposed to air or water. Also gas cooled breeder reactors are possible, using helium, CO2, or N2, again not explosive when exposed to air or water. The British, Germans, Japanese, South Africans, and USA experimented with this coolant as well.

    Finlay for a breeder reactor to make sense the fuel fresh out of the breeder must be reprocessed. Considering Carter made reprocessing illegal in the USA, it is no big surprise that the program floundered then failed.
  8. Jun 27, 2011 #7
    Thanks for all the replies - I'll check out those links now!
  9. Jun 27, 2011 #8
    It's a technical nightmare to build and operate one. Reprocessing the fuel is even more nightmarish. The French tried and gave up (google Phenix, Superphenix, La Hague). The Japanese are still trying, with pathetic results (google Monju, Rokkasho). The US looked at it, built a technology demonstrator, never quite got around to actually, y'know, breeding fuel and stopped.

    India is in the prototype phase with a water-cooled thorium breeder based on the CANDU design I think. Good luck to them. The Chinese are also making noise, but they have no working reactors, or a finalized design, iirc.

    The molten metal approach to cooling, in general, is plagued by technical difficulties. You can't see inside as you can in a BWR, you can't let the coolant solidify if you don't want to write off the reactor, it's very hard to decontaminate the coolant if fuel elements were to fail, the metals or alloys used are very corrosive (and in the case of sodium, go boom in the presence of air or water) etc etc.

    The lead-bismuth cooled reactors operated by the Russian navy were never refueled. They had been designed with fuel cassettes, so that the whole core could be swapped at once (no fancy breeder cycle there), but even so it was too much of a challenge.
  10. Jun 27, 2011 #9
    At least from reading the Wikipedia, it seems that the reasons for closing most of the plants you mentioned were mainly because of the political influence of the protesters (who were paranoid about anything nuclear). Or in the case of Rokkasho, because it was found to be built on a geological fault.

    Are there any alternatives to cooling? How much energy (relative to the total energy produced in the fission process) does it take to keep the metals above melting point?
  11. Jun 27, 2011 #10
    Most FBRs have been much smaller in power output than typical LWRs. The Phenix FBR was 233 MWe. The German SNR-300 was 300 MWe. The PFR in Dounreay, Scotland was 250 MWe. The Monju FBR was 280 MWe. The French Super-Phenix was the only FBR ever built with more than 1000 MWe.

    This is no coincidence. There's a trade-off when you scale up the core, as fewer neutrons make it out of the core and into the breeding blanket of depleted uranium. The design can't be scaled up too far without sacrificing its main selling point. If you want to show off a good breeding ratio you need to stick with reactors that are much smaller than modern LWRs, but at the same time the technical challenges (liquid metal cooling, higher temperatures, etc) mean that the reactor ends up costing maybe twice as much to build than an LWR putting out 4 or 5 times the power.

    That simply does not compute. At 10x the capital cost per kW you'd be cheaper off either sticking with LWRs or going for renewable sources. Even solar at current prices is cheaper, without the proliferation risks.

    Also there are no reprocessing facilities for spent FBR fuel, which poses special challenges because of high burn-up rates and buildup of trans-uranium elements, leaving a gaping hole in the so-called fuel cycle of FBRs.
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