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Once through nuclear fission designs seems horribly wasteful & polluting

  1. Mar 21, 2007 #1
    Esp given that most of the energy has yet to be tapped
     
  2. jcsd
  3. Mar 21, 2007 #2

    Astronuc

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    It does seem that way.

    However, it depends upon the front-end cost (primarily cost of U-ore) and the relative back-end costs (storage, transportation, reprocessing and subsequent storage of radioactive waste either as spent fuel or vitrified FP).

    Also, reprocessed fuel has to be manufactured with remote handling which greatly increases the cost of manufacture.

    With low cost of U-ore and other factors, it has been less expensive to do the once-through fuel cycle than to reprocess.
     
  4. Mar 22, 2007 #3

    Morbius

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    ensabah6,

    Yes - it is wasteful. The nuclear power program in the USA had originally intended to
    reprocess spent nuclear fuel and recycle fissile material back to the reactors.

    However, in the early '70s when this was about to happen, the anti-nuclear crowd went to
    Court and it was ruled that the U.S. Government had to comply with the newly passed
    Environmental Protection Act, and do an evironmental impact statement on the decision
    to reprocess nuclear waste.

    The environmental impacts were studied, and in the middle '70s, the Government released
    the GESMO - Generic Environmental Statement on Mixed Oxide. However, the anti-nukes
    had also been busy; they got the Congress to pass a law to OUTLAW reprocessing
    spent nuclear fuel.

    Dr. Gregory Greenman
    Physicist
     
  5. Mar 22, 2007 #4

    Andrew Mason

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    In terms of potentially accessible energy locked up in matter it is very wasteful. This is fuel that will not produce green-house gases when converted to energy. Since only 1% of the available fuel is used, the once-through fuel cycle is 100 times as wasteful as it could be.

    The environmental costs, however, of mining and waste disposal are thousands of times greater than they need be. Rich deposits (in Saskatchewan there are two large rich deposits at 24% U) are depleted 100 times more quickly. So we end up mining low grade deposits a lot sooner than we have to and instead of 24% ore we will be mining .1% ore (e.g Australia). And the waste from the once-through fuel is much longer lived (about 1000 times longer) and greater volume (100 times) than waste consisting of just fission products. The costs of dealing with this waste are several orders of magnitude greater than they need be.

    AM
     
  6. Mar 24, 2007 #5

    Astronuc

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    That actually applies more to CANDU's. In LWRs, batch average burnups have been slowly increasing to the range of 4-5%, or even 6% FIMA. Of course, that includes the fission of Pu-239 and Pu-241 at higher burnups where about 50% of the fissions are from Pu isotopes which arise from the conversion of U-238 through successive n-capture.
     
  7. Mar 24, 2007 #6

    Andrew Mason

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    You are ignoring the depleted U that comes out of the enrichment plants. If you take the DU into account you are back to around 1%. If you subtract the energy required for enrichment you are down to less than 1%.

    Candu reactors use natural uranium at .7% U235 and the waste is at about .2%. But the reactor also fissions Pu239. About 30% of the energy from a Candu is from fission of Pu. So that brings the fuel use to about .7%.

    The Candu, however, can burn the waste from an LWR, which contains about 1.5-2% (slightly enriched U - SEU). In fact, this is one of the big selling points to countries like China.

    AM
     
  8. Mar 28, 2007 #7
    Eco-green opposition to recycling?? The hell?
     
  9. Mar 28, 2007 #8

    Morbius

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    ensabah6,

    "Eco-green" opposition to nuclear power.

    It's quite apparent what their strategy is. If they don't allow recycling, and don't allow
    a disposal facility like Yucca Mountain; and oppose on-site "dry cask" storage; then
    sooner or later - the nuclear utilities will run out of space to put spent reactor fuel.

    If they don't have any place to put spent fuel; they can't unload the reactor. If you
    can't unload the reactor; you can't load it with fresh fuel. If you can't load with fresh
    fuel - you can't operate the reactor. From the viewpoint of the so-called "eco-greens";
    that's MISSION ACCOMPLISHED.

    Dr. Gregory Greenman
    Physicist
     
  10. Mar 28, 2007 #9
    So they would prefer we burn fossil fuels which emit CO2 which contributes to global warming?
     
  11. Mar 29, 2007 #10

    Morbius

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    ensabah6,

    Whether that is their intent or not; that IS the effect.

    The USA hasn't built a new nuclear power plant for about 3 decades; the last nuclear
    power plant that was ordered and completed was ordered in 1974.

    However, the USA has in that same time frame built plenty of fossil fuel plants; and
    continues to do so.

    What is ironic, is that about 50% of the USA's installed electric generating capaicty is
    COAL power plants. Coal plants emit 100X as much radioactivity as do nuclear power
    plants due to the trace amounts of uranium and thorium in coal. From a report by the
    Oak Ridge National Laboratory:

    http://www.ornl.gov/info/ornlreview/rev26-34/text/colmain.html

    So for all the hyteria on the part of the "eco-green" anti-nukes about how bad nuclear
    power is because of the radioactivity; the power plants that were actually built instead
    of nuclear power plants are emitting 100X as much radioactivity due to the fact that
    they throw about 14,000 tons of uranium and thorium into the atmosphere ANNUALLY!!!
    They have been doing that each and every year for the last 3 decades.

    Thank you "eco-greens". NOT!!!

    Dr. Gregory Greenman
    Physicist
     
  12. Mar 29, 2007 #11

    I understand that non-USA nations like France, Japan, and S. Korea. even Iran are going nuke.

    What nuke design do you feel is best for the environment yet cost competitive with fossil fuel? How do you feel about Iran going nuke and USA/Israel's promise to destroy it?
     
  13. Mar 29, 2007 #12

    Morbius

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    ensabah6,

    If you don't have protestors holding up the building and licensing; then current reactor
    designs are quite competitive with fossil fuels. Coal has only a slight cost advantage -
    but's that's discounting the environmental damage costs - no need to give coal a free
    ride on those.

    Nuclear and gas are about the same in price.

    The reactor manufacturers have even better designs on the drawing boards. I like the
    IFR system from Argonne National Lab:

    http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/till.html

    Iran's activities make me uncomfortable. If they really were interested in nuclear power
    just for the electricity, then they shouldn't have had ANY problem with the Russian
    proposal to locate the enrichment facilities inside Russia, where Russia could have
    oversight and make sure it was not used for weapons.

    I'm afraid Iran wants enrichment capability not for commercial power; but for
    nuclear weapons. If we are naive about this; we do so at our own peril.

    Dr. Gregory Greenman
    Physicist
     
  14. Mar 29, 2007 #13

    I agree 100% -- are there any IFR (or just ordinary nuclear power plants) being built outside the USA?

    If, for example, Asia or Europe or South America builds new nuclear plants that could help curb greenhouse emissions.
     
  15. Mar 29, 2007 #14

    Morbius

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    ensabah6,

    Oh my heavens - YES.

    Japan is building new nuclear power plants, China is building new nuclear power plants;
    France never stopped buiding nuclear power plants.

    At last recall, France was about 85% nuclear generated electricity.

    http://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/french.html

    http://www.uic.com.au/nip28.htm
    http://www.uic.com.au/nip08.htm
    http://www.post-gazette.com/pg/06087/677490-28.stm

    Japan:
    http://www.japannuclear.com/

    China:
    http://www.eia.doe.gov/cneaf/nuclear/page/nuc_reactors/china/china.html
    http://english.people.com.cn/200210/24/eng20021024_105574.shtml

    Dr. Gregory Greenman
    Physicist
     
  16. Mar 29, 2007 #15

    Andrew Mason

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    If you add that to the fact that in China alone (where they are reportedly building a new coal plant every 10 days) there is a huge death toll from mining coal. This site says there are about 6000 deaths in China per year.

    This does not even deal with the huge number of pre-mature deaths due to black-lung, and other occupational diseases and the thousands of premature deaths each year due to breathing the atmospheric pollutants caused by coal burning. It is estimated by the EPA that 24,000 such deaths occur in the US each year: http://www.msnbc.msn.com/id/5174391/ .

    The overall negative effects on the economy are staggering, if you take into account medical costs, lost time from work, early retirements etc. see: http://www.ecomall.com/greenshopping/cleanair.htm

    If you add the long term environmental costs due to global warming, and ocean acidification to the occupational health and safety and pollution related costs/deaths around the world, the toll is mindboggling. If nuclear had 1 millionth of the known dangers that coal produces............

    AM
     
  17. Mar 29, 2007 #16
  18. Mar 30, 2007 #17
    So Nuke is doing well outside the USA. Is eco-crazies the only reason it is doing poorly in the USA, and there are few anti-nuke eco-nuts outside the USA, such as France?
     
  19. Mar 30, 2007 #18

    Morbius

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    ensabah6,

    The French, for the most part; LIKE their nuclear power plants:

    http://www.pbs.org/wgbh/pages/frontline/shows/reaction/readings/french.html

    The USA has the problems. For some insight, see what a psychiatrist says:

    http://www.pbs.org/wgbh/pages/frontline/shows/reaction/interviews/dupont.html

    Dr. Gregory Greenman
    Physicist
     
  20. Mar 30, 2007 #19
    I don't think nuclear related subjects are doing too poorly in the US, certainly people come to the US to study it, and it is one of the top three producers of electric power from nuclear plants in the world.
    I think every country has people opposed to nuclear power. I read an article not too long ago about Greenpeace protestors climbing up a nuclear plant cooling tower and defacing it in France. Germany is supposed to be getting rid of some of their nuclear power plants, I guess the Green party has some strong support.
     
  21. Mar 30, 2007 #20

    Morbius

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    Candyman,

    Yes - nuclear power is about 20% of the installed capacity in the USA; that's nothing to
    sneeze at. In some places, like northern Illinois and Chicago and its suburbs; the are
    served by Commonwealth Edison or its successors; there is a much larger fraction of
    nuclear energy; almost as high a percentage as France. As I recall, there are, or have
    been about 13 reactors in northern Illinois. Some like Dresden 1, and Zion 1 and 2 are
    now shutdown.

    Dr. Gregory Greenman
    Physicist
     
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