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Japan Power News

Japan Raises Nuclear Plant Crisis Severity To 7 673

darkonc writes "Early Tuesday in Japan, the government decided to raise the severity level of the accident to the maximum 7 on an international scale, up from the current 5 and matching that of the 1986 Chernobyl catastrophe. The government declared the level 7 emergency because it is now estimated that the crippled plant was emitting over 10,000 terabecquerels of radioactivity for a number of hours at the height of the nuclear incident. Previously, on Monday, the government had expanded the evacuation zone around the plant to include at least 6 cities up to 60 km away from the plant. These cities, outside of the current 20-30 km evacuation area, are now expected to exceed the 20 millisieverts/year limit on residual radiation established by International Commission on Radiological Protection and the International Atomic Energy Agency in the case of an emergency."
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Japan Raises Nuclear Plant Crisis Severity To 7

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  • watch this video (Score:3, Informative)

    by Anonymous Coward on Tuesday April 12, 2011 @08:40AM (#35791814)

    You can't really put things into perspective until you look at this video:

    A few filmmakers went into the evacuation zone. Watch how those geiger counters are going ballistic miles from the plant. Whole cities are going to be ghost towns for our lifetime for sure.

  • Re:Japanese whispers (Score:4, Informative)

    by Rakshasa Taisab ( 244699 ) on Tuesday April 12, 2011 @08:57AM (#35792002) Homepage
    Except one blew lots of plutonium and other fun stuff into the atmosphere, while the other has released mostly radioactive iodine and cesium.
  • by Mindcontrolled ( 1388007 ) on Tuesday April 12, 2011 @09:15AM (#35792226)
    As the saying goes, you are entitled to your opinion, but not to your own facts. Concentrated solar thermal can drive steam turbines, molten salt storage can buffer the nighttime. Here's one tiny, insignificant manufacturer [].
  • by vlm ( 69642 ) on Tuesday April 12, 2011 @09:19AM (#35792264)

    I'd be curious about whether a pebble bed reactor would have fared better.

    Probably "about" as risky but completely different failure modes. The pebbles are brittle and are going to have issues with a severe earthquake, unlike literally "depth charge proof" light water reactors. If the pebbles don't crack and no coolant leaks, they are harmless. One or the other fails, still harmless. Both simultaneously fail, instant Chernobyl because its yet another graphite moderated design. Once you set one (or a couple) pebbles on fire, it gets hot enough to catch all the pebbles despite the coating, so you gotta spray it down, which means thermal stress will crack em all, making a bigger fire or at least a heck of a mess.

    Most exciting failure mode for a pebble bed would probably be chilling the graphite moderator (tsunami? Pump in sea water?), which eliminates doppler broadening, which turns the power WAY up, at least momentarily. Pop those little tennis balls like popcorn. Then all that red hot graphite can boil off the water and/or make old fashioned town-gas (mostly carbon monoxide gas) which explodes the containment, then the burning graphite roasts all the fission products into the air. Yeah it would be pretty bad.

    So the lesson learned from Chernobyl is don't use a flammable moderator. (except, apparently, for the pebble bed fans)

    The lesson from Japan is going to be don't use flammable cladding, and who cares what the alternatives do to the neutron balance.

    The good news, is once we utterly ban flammable cladding, there's not much in a core that's still flammable, so our problems are pretty much over.

    I suppose we need one more good fire / meltdown of a uranium carbide fueled reactor so we can ban carbide fuel. Then we're all good...

    Without the fire / explosion, the Japan thing would still be a complete economic loss, but there would be no contamination outside the containment structure.

  • by MightyYar ( 622222 ) on Tuesday April 12, 2011 @09:20AM (#35792300)

    And some people still wonder why the public are opposed to nuclear power.

    I don't wonder why. I see a media that gets readership/viewership with sensationalist headlines. I see a nuclear industry that feels backed into a corner and so releases pro-nuclear statements that are laughable in any context, let alone in the midst of one of the worst nuclear accidents of all time.

    But at the end of the day, the facts are these:
    1. The direct cause of this nuclear accident was a catastrophic earthquake and tsunami.
    2. The earthquake/tsunami has killed thousands - maybe 20,000 when all is said and done. The nuclear accident has killed 0. In the long term, it probably has shortened the lives of some plant workers. I'm sure it will get blamed for a couple of hundred cancers.
    4. The earthquake/tsunami has caused hundreds of BILLIONS of dollars in damage. It will take decades to rebuild. The nuclear accident will probably take 10 years or so and hundreds of MILLIONS of dollars to clean up.

    In other words, in the context of the greater disaster, Fukushima is a mess and complicates reconstruction and rescue - but it is not really comparable in numeric terms. We should certainly learn lessons from it and retrofit plants using these lessons - and close those that can't be fixed. But abandon nuclear power? In favor of what? Coal?

  • Re:watch this video (Score:5, Informative)

    by Ptur ( 866963 ) on Tuesday April 12, 2011 @09:28AM (#35792406)
    This is a prime example of journalists creating hysteria based on their ignorance. The scale on their device never went over 100uS/hr - that's MICRO-Sieverts.... To put this in perspective, read []

    They never risked their lives at all
  • by gilleain ( 1310105 ) on Tuesday April 12, 2011 @09:39AM (#35792558)

    Plutonium does not exist naturally on earth, it's extremely toxic, and it lasts for millions of years.

    From wikipedia: "Plutonium is the heaviest primordial element (see also primordial nuclide), by virtue of its most stable isotope, plutonium-244, whose half-life of about 80 million years is just long enough for the element to be found in trace quantities in nature." It exists in nature because it lasts for millions of years.

  • Re:watch this video (Score:5, Informative)

    by ZZane ( 144066 ) on Tuesday April 12, 2011 @10:29AM (#35793252)

    100uS/hr = 2.4mSv per day = 876mSv/year

    So while the journalists didn't risk their lives with that dose, it's definitely not a livable area at those radiation levels. However, depending on the source of the radiation those levels could go down fairly quickly or it could remain at those levels for quite a long time. Of course that assumes no further contamination from the plant.

  • by mdsolar ( 1045926 ) on Tuesday April 12, 2011 @10:41AM (#35793434) Homepage Journal
    About 46% of US generation can be replaced by rooftop solar given available residential roof space. But, net metering policy which confiscates excess power generation without compensation probably limits this source to 22%. [] Feed in tariffs would remove the artificial barrier. The price for panels now is about $2/Watt and will fall below $0.5/Watt before half of that capacity is installed. Installation may get down to $1/Watt as panels get lighter and more efficient. Inverters are about $0.5/Watt now and will go lower. So, a typical price for the bulk of installations will be below $2/Watt. Nuclear power plant construction costs $12/Watt and the cost is increasing. Not considering fuel costs and operating expenses for nuclear, and factoring in availability assuming similar life times, rooftop solar costs about 60% of the cost of nuclear. Desert solar likely costs less than half of nuclear.
  • by Luckyo ( 1726890 ) on Tuesday April 12, 2011 @12:10PM (#35794874)

    Darling, just a few hundred kilometers to the east, here in Finland we have hydro power plants on about every available river.

    They generated a total of 14.6% of country's electricity in year 2010. Even with 4 nukes, lots of coal, gas, biomass, etc power plants, we still have to buy electricity from Tsernobyl-type reactors at Sosnovy Bor for almost as much (12.0%).

    So please, don't talk about things you know nothing about. Thank you.

10.0 times 0.1 is hardly ever 1.0.