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This discussion relates to Technology Review's article A Preassembled Nuclear Reactor.

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  lasertekk
  

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  06/16/2009 10:11 AM

  [no subject]

  Does the factory take responsibility for storing the spent waste and contaminated components?

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    kstauff
    

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    06/16/2009 10:48 AM

    Re:

    As Kevin linked in the article, the federal government has taken on the obligation to provide a safe disposal site or sites for nuclear waste.  New reactor designs can reuse spent fuel to further reduce the amount of waste that needs to be stored. 
    
    Unfortunately, after years of hand wringing, the Obama administration killed the Yucca Mountain disposal site, effectively starting over the search and study of a new site or sites.  They'll likely spend another 10-15 years trying to find an alternative. 
    
    So, it would appear that our government is failing to keep its word, at least from a practical standpoint.  They're playing politics with nuclear and other forms of energy, and the consumer/tax payer will be the one paying for it.

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  dmbodeen
  

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  06/16/2009 10:36 AM

  an even better solution

  check out this website. http://www.hyperionpowergeneration.com/
  
  They offer a much smaller nuclear reactor solution that is far cheaper and has very little waste. Very interesting technology.

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    paulreedsmith
    

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    06/20/2009 07:33 AM

    Re: an even better solution

    Two issues with nuke waste that are generally misunderstood: Since Yucca, that the the utility industry has so far funded with $30+ billion from a surcharge of (as recollected) a tenth of a cent per Kwh, is dead, on-site storage is going to be around for a long time. After a year or two in pond storage, the waste is thermally cool enough to go into cask storage, certified for a few hundred years, but they may be good for about a thousand years. If one took all the potential waste from the 104 plants now operating over a 60 year life cycle and put the casks on ten foot centers, all nuke waste in the country would fit in a square 810 feet on a side - that's it. Second: Is this "waste" - or an "asset"? Since, in the late 1970s, the Feds stopped the reprocessing option we use the "once through" cycle that only uses about 5% of the potential energy of the initial fuel load. Practically all that's left over is depleted uranium (U-238)that is a potential fuel source for fast neutron reactors, like the Russian BN-600 lead cooled reactor that's been working pretty flawlessly since the early 1980s. Energy Secretary Chu (sp?) noted this "asset-liability" issue about nuke waste: A very small percentage of what is in the waste stream is composed of long-lived actinides that would need perpetual entombment. Does it therefore make sense to bury all the waste when over 90% of it could be used as a new fuel source? Another possible point re capital costs: Yes, nukes represent a big-dollar investment, but one gets big power. One wind turbine is cheap by comparison, but when one figures in power availability, maintenance - and the fact a turbine is going to last a fraction of the time of a nuclear power plant - some calculations show that looking at actual delivered power (what really counts!) nukes are the cheapest source. One possible date point: Denmark has the highest wind percentage in the EU, France the highest nuke percentage. Denmark has the most expensive electricity, France the cheapest.

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      robw
      

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      06/21/2009 08:16 PM

      Re: an even better solution

      and not only that, if we immediately implemented Integral Fast Reactors, as pointed our in Tom Blees excellent book 'Prescription for the Planet', we could live off of nuclear waste and depleted uranium, enough to power the entire planet for hundreds or years, without having to mine an ounce of new uranium.
      
      And if that's not enough, Liquid Fluoride Thorium Reactors could run the planet for a lot longer, as thorium is 4x as abundant as uranium.
      

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    sketerpot
    

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    06/29/2009 08:13 PM

    Re: an even better solution

    Hyperion's reactor is a relatively novel design with a smallish company behind it. The mPower reactor, in contrast, is a very conservative design with a big, established company backing it. I think that mPower will help pave the way for technically superior reactors like the Hyperion power module, but mPower is definitely a safer bet in the short term.

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  tinker
  

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  06/16/2009 11:37 AM

  Terrorism

  Just a thought, won't it be easy for the terrorist to steal these small containment nuclear reactors and disassemble them to extract materials required for their WMD?

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    dmbodeen
    

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    06/16/2009 11:51 AM

    Re: Terrorism

    The version of reactor that I refer to is buried 100 ft underground, requires no matience such as loading fuel rods or dealing with spent fuel rods. Check it out. It makes a lot of sense.

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      paulreedsmith
      

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      06/20/2009 07:49 AM

      Re: Terrorism

      No one has ever made a bomb from the waste stream of a LWR - or ever will. Bomb-grade plutonium has to be at around 95% PU-239. I'll spare you how plutonium is produced in a reactor from a uranium fuel load, but after one year in a reactor the PU-239 has been transmuted and about 20% of the PU has become PU-240, not only a bomb makers nightmare as it randomly emits neutrons, but also prohibits critical mass from being achieved. Weapons grade PU is produced in special "bomb factory" reactors where it is a quick in-and-out process to brew up a fairly pure batch of PU-239. (This is what the Soviet RMBK reactors, viz Chernobyl, were designed for. This design had a positive void coefficient of reactivity - all US nukes are negative - and this design was prohibited for civilian use here in the early 1950s; any nuclear engineer knew this design was inherently unstable and subject to ...)

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    Jim Hopf
    

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    06/17/2009 02:21 AM

    Re: Terrorism

    No, it would be incredibly difficult.
    
    We're talking about a sealed, underground facility with heavy security.  You have to get down into the reactor building, then inside the sealed, thick-steel containment, then inside the reactor (thicker steel), etc....  Then you have to move intensely readioactive spent fuel, which kills you unless it's inside a ~100 tone shielded cask, which requires heavy cranes to lift, etc..
    
    And after all that, you don't even wind up with anything all that useful.  Power plant spent fuel is even harder to convert into a weapon than raw uranium ore that you can just dig up anywhere (and then enrich).  That's what Iran is doing, BTW.  Reactors have nothing to do with it.
    
    As for dirty bombs, spent fuel is less effective, and harder to employ, than the concentrated radioisotope sources that are located at hospitals all over the country.  These small, concenrtated sources are much easier to handle, and steal (a man could lift the container), and they are under minimal security.  Once stolen, they make a much more effective dirty bomb (not that a dirty bomb would result in many deaths, anyway).

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