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Japan's Last Nuclear Reactor Shuts Down

AmiMoJo writes "Japan's last active reactor is shutting down today, leaving the country without nuclear energy for the first time since 1970. All 50 commercial reactors in the country are now offline. 19 have completed stress tests but there is little prospect of them being restarted due to heavy opposition from local governments. Meanwhile activists in Tokyo celebrated the shutdown and asked the government to admit that nuclear power was no longer needed in Japan and to concentrate on safety. If this summer turns out to be as hot as 2010 some areas could be asked to make 15% power savings to avoid shortages, while other areas will be unaffected due to savings already made."

9 of 452 comments (clear)

  1. Thorium Nuclear by iCEBaLM · · Score: 4, Informative

    We need to start making some of these Thorium reactors.

    1. Re:Thorium Nuclear by cbarcus · · Score: 5, Informative

      This comment is very far off.

      Unlike molten salt reactors, a class of fast breeders utilize liquid sodium, which reacts violently with water- and has been a bit of a problem (very costly) when heat-exchangers, reheaters, and similar equipment fails.

      Molten salt reactors, like the one prototyped at Oak Ridge National Laboratories back in the 60s, ran for years. The corrosion issue stems from the inadvertent production of tritium (from an undesired isotope of lithium in some formulations of the salt) which can combine with the fluorine (Liquid Fluoride Thorium Reactor/LFTR) to produce a strong acid. These and other problems appear to have very viable solutions (from listening to the relevant scientists and engineers), and should not be used to disparage the technology.

      To compare this fission technology that has already been demonstrated in principle with a prototype, to fusion which has not even achieved break-even demonstrates a serious lack of understanding of the issues involved. The primary advantages of the molten salt reactor to energy production are the following:
      - based on fission which is a well-understood phenomena; U-233 liquid-fueled reactor already demonstrated in principle decades ago (found to be very reliable)
      - a liquid fuel system that operates at low pressure and high temperature which allows for very high levels of safety and efficiency
      - the above which contribute to the high likelihood of low-cost reactors
      - low cost reactors will dramatically lower the cost of carbon-free energy
      - high temperatures allow for more efficient cogeneration; example: ammonia synthesis which could be used as an energy carrier on the scale of petroleum, which would address both concerns about fuel supply and carbon emissions
      - high temperatures also allow for the use of dry cooling (as opposed to "wet" cooling which uses a lot of water), necessary for an efficient thermodynamic cycle
      - thorium fuel is about as abundant as lead (3-4 times more abundant as uranium), and so very low cost
      - fissile startup requirements are minimal (less than a tonne of 20% enriched U-235 is possible)
      - system is very proliferation resistant (lots of technical details in the specifics)

      The disadvantages:
      - we must face our fear of nuclear energy
      - more R&D (substantially less than $10 billion) will be required before this technology is a commercial reality
      - bureaucratic and industry resistance to a new technology (they've already committed themselves to something else which is not suited for solving our systemic problems)
      - the general public remains woefully ignorant of the risks it is facing by foregoing nuclear energy

      The potential is that we have a nuclear system that is so safe and efficient that it may have the convenience, but at lower cost, than modern and ubiquitous natural gas plants. We are looking at perhaps the greatest technology humanity has ever developed, at best critical to our transition to a sustainable existence, and at worst, an essential technological step to reduce the risk we currently face. The United States may lack the technical leadership to step into a new era of low-cost carbon-free energy, but its rivals are seriously looking at this approach (China is apparently putting around $100 million annually into this), and if it proves viable on a commercial scale (all signs so far showing absolutely "yes"), the US will be left behind. It is difficult to overstate the importance of this issue to national security. Our economic well-being is dependent upon the cost and convenience of energy, and "farming" low-density energy sources dramatically increases our risk in this area. Lower the cost of energy and you will facilitate wealth creation, otherwise we face recession and decline.

  2. Re:Oh Great by jklovanc · · Score: 5, Informative

    According to this Fukushima 4's fuel was removed soon after the disaster and therefore has been shut down for some time.

  3. Re:Good job japan! by Anonymous Coward · · Score: 5, Informative

    The activists have a point. The reactor designs are relatively unsafe compared to modern designs, though it took a hell of a lot of punishment to show it.

    Here's hoping Japan makes the switch to thorium.

    Except the Activist are against the building of newer safer designs.

  4. This is pushing up the price of oil. by Animats · · Score: 4, Informative

    Japan has essentially no internal oil or natural gas resources. Everything has to be imported. As a result of the nuclear shutdown, imports are up. Way up. So are prices.

    From the Financial Times:

    As utilities last year met the shortfall of nuclear power, Japanese consumption of LNG rose by 56 per cent, crude oil for direct burning by 27 per cent and fuel oil usage by 20 per cent. The trend, which is helping to keep spot LNG prices in Asia and global oil prices higher, is set to accelerate in the next few months as utilities burn more hydrocarbons to compensate for the lack of nuclear power.

    Energy analysts say utilities have maximised LNG-fired electricity output, leaving crude oil and fuel oil to meet additional needs. Oil traders believe that Japan's nuclear cutback could add between 450,000 and 800,000 barrels a day to world demand for crude and fuel oil. The figures are significant. The bottom end of the range equals the production of Ecuador and the upper end matches the output of Qatar.

  5. Re:Save Face, not Environment by K.+S.+Kyosuke · · Score: 4, Informative

    1. We are using, in one way or another, 50% of all *SOLAR* energy that falls on this planet

    Are you joking? Do you have any idea how much energy are those 50% of Earth's total incident solar radiation? Our civilization is in no way consuming anything near those 87,000 TW. It's currently somewhere around 15 TW.

    --
    Ezekiel 23:20
  6. Re:It's not just misinformation by thegarbz · · Score: 4, Informative

    Some context for others reading your post:

    https://en.wikipedia.org/wiki/Banqiao_Dam

    Effectively Hydro is the king of devastating disasters in the power industry. Yet most people haven't even heard about this incident.

  7. Re:It's not just misinformation by gstrickler · · Score: 4, Informative

    Your ignorance is showing. The notable fission products released from a nuclear plant accident are 131I, 137Cs, and 90Sr. 131I has a half-life of just over 8 days. In 80 days, it's 1/1000 the level, in 160 days, 1/1M, in 240 days 1/1B. It's a short term hazard.

    137Cs and 90Sr each have a half-life of ~30yrs, making them a factor for up to 600 years. Both are beta emitters, so they're primarily a hazard only when inhaled, ingested, or with direct skin contact. However, 90Sr isn't produced in large quantities, so it's not a major factor. That leaves 137Cs. The main concern with 137Cs is with unknown/untreated exposure. It's easy and fairly cheap to treat exposure (including land) if you know about the contamination. 137Cs and 131I are the primary isotopes released at both Chernobyl and Fukushima.

    So, what about the others. 238U (4.4B yrs) and 235U (700M yrs) in the fuel have such long half-lives and are primarily alpha emitters, such that you can hold them with just gloves.

    Uranium fueled reactors will produce small amounts of 239Pu (24,100 yrs), 242Pu (373K yrs), and 241Pu (14yrs) The 241Pu is the most radioactive of these, but it's produces in much lower quantities than the other two. The other two are less radioactive, and are produced in small quantities. Contrary to urban legend, Pu is not "the deadliest substance known", in fact, the body generally won't absorb it even if eaten (definitely not recommended). The real risk from Pu is if it's inhaled, and still, due to the long half-life of 239Pu and 242Pu, you would have to inhale a notable number of atoms to have any likelihood of increased risk.

    And if you switch to thorium fueled reactors, they produce virtually no plutonium, and no weapons grade uranium. The do produce some different isotopes that need to be managed. Overall, they're significantly "cleaner" and "safer" than a uranium fuel cycle.

    In either case, using fuel reprocessing, you drastically reduce the nuclear waste. If you do it well, you can separate it into short-lived waste that needs only to be buried for ~400 years, and long-lived waste, which is less of a risk, and could be safely mixed in with the original ore from which the Ur or Th was mined. That ore would be less radioactive than it was before mining. Yes, I did just say that we could dispose of "radioactive waste" by putting it back where we originally mined the Ur/Th, AND that that would leave LESS radiation in the environment than was there naturally.

    That would require people get over the fear of the terms "nuclear" and "radiation" (which we're exposed to constantly), and it would require changes in environmental regulations. I know it sounds scary, to put the waste back into the tailings from which it was mined, but that's actually the safest way to dispose of it, and it has a net effect of reducing radiation in the environment.

    --
    make imaginary.friends COUNT=100 VISIBLE=false
  8. Re:Greenies have won while the majority in Japan l by wrook · · Score: 5, Informative

    They want modern clean technology like wind and geothermal.

    Instead of just guessing what they want why not try simply listening to them.

    Though, I'm not originally from here, I live in Japan. You have absolutely no idea what you are talking about.

    I talk to Japanese people every day. They are against nuclear power. At best, people don't mind wind power. At least most people don't actively complain about the new windmills being put up (and there are a lot going up). But nobody is calling for them as far as I can tell. But people here do NOT want geothermal. There is a fear that it will somehow destroy the onsens (hot springs). This is a major problem, because we have *no* domestic base load generation capacity except geothermal. Even now, as far as I can tell, there is *no* move to find new geothermal wells.

    There is, unfortunately, a media fuelled misconception that solar power will solve all the problems. Granted, where I live, it is quite feasible to run most of your house on solar power. But we still need base load generation and we don't have it.

    Don't get me wrong. As far as I'm concerned, nuclear was only a stop gap for Japan. It gave us some time to sort out new technologies. It's not like Japan has a domestic supply of nuclear fuel. But by shutting down all the reactors, it really puts the pinch on. I just hope we end up going the right direction in the end...