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San Onofre's Closure: What Was Missed 88

Lasrick writes "John Mecklin explores the context that was missed when the LA Times and the San Diego Union Tribune reported on the closing of the remaining two San Onofre nuclear reactors: 'U-T San Diego published a similar flurry of well-reported stories that covered the basics of the reasons for the closure, as well as the impact on consumers, workers, and the electricity supply. At both papers, coverage included infographics that effectively explained the problem that forced the plant to close—vibration that caused wear in tubes for the plant's steam generators. (The Times's tick-tock takeout on the history of the steam generator snafu, published in July, is especially comprehensive.) The specifics of the San Onofre closing were covered well and thoroughly. The context within which those basics reside, however, was far less well-examined, and the two major newspapers closest to the San Onofre plant both therefore missed a real opportunity to inform readers about the major energy choices California and the country will need to make in the coming decade.' Excellent work at the Columbia Journalism Review."
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San Onofre's Closure: What Was Missed

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  • Economics (Score:5, Insightful)

    by fermion ( 181285 ) on Monday July 15, 2013 @08:05PM (#44290635) Homepage Journal
    A rational person would have stopped when they said that economics closed nuclear power. This is the reality. In the US there has been 40 years to prove that nuclear energy is a competitive product. You can blame the government, but it is pretty much bad management of a technology that could work. You can say if the government would only subsidize the product, it would work, but why is government subsidizing a mature technology? In the US it does not seem to be a viable solution.

    Yes coal is a major source of electricity, about 40%, and it is going to get harder with new regulation. But again, like nuclear, the reason we building more coal plants it dogma. People believe it is the best solution. It is certainly a profitable solution. There are tens of thousands of people who are willing to dig coal for a middle class income in working conditions that keep the overall costs low. So we have the job argument, the argument that we can't live without electricity, and the argument that technology will make it cleaner. But that technology is funded by the taxpayer, and maybe we want to do something new that will help us long term, not just keep established corporations in power.

    In any case, the short term future is natural gas, and the long term future is wind, solar, and conservation. This is where the technology is. Building more efficient electronics. Building better turbines and solar cells. Building superconducting batteries, storing energy in elevated mass, flywheels, etc so that we are not generating for peak capacity 24 hours a day, and then throwing away a quarter of it. It is not something that your C level executive understands, it is not something your coal miner wants to go to school to learn, it is not something that is going to transfer millions of dollars of tax payers money directly into the pockets of investors, but it is something that will build the intellectual and long term economic wealth of the country.

    And I mentions conservation. These plants supplied one millions homes in a state of 38 million. That is 2% reduction in capacity. The big thing we need to realize is that energy is neither free nor infinate. We can go and buy a 60" TV that us going to use almost 400KWh in a year, or one that uses under 200. We can browse on our 120 watt computer, or on our 5W tablet. We can turn on the lights in the middle of the day, or not. How much would we need to do to save 2% of the electricity? Who much would be need to do to save 10%?

  • Re:Economics (Score:2, Insightful)

    by cheesybagel ( 670288 ) on Monday July 15, 2013 @08:42PM (#44291015)

    Actually the reality is that nuclear power is economic over the entire lifetime of a plant, nearly as cheap as coal, and works just fine without particulate emissions.

    Solar power will eventually be interesting enough for grid generation but for now it remains too expensive. Not to mention that these technologies have issues regarding availability. As for storage there have been a lot of people working on it but it neither comes cheap, nor does it come without losses.

    Conservation only works when you actually have generated energy to conserve.

  • Re:Ironic? (Score:4, Insightful)

    by dj245 ( 732906 ) on Monday July 15, 2013 @10:09PM (#44291893) Homepage

    An article that decries all the valuable, important stuff that could have been brought up, but then doesn't bother to bring them up and/or discuss them in any detail?

    This article was a waste of my time. I wish Slashdot had a thumbs up/down on articles.

    Well I can't speak for the nuclear side of it, but the steam turbines had problems too. One was that they were getting buildup in the generator stator core cooling tubes.
    See, a large steam turbine like this has a really massive electric generator. In most motors that people think of, the windings are made of copper wire. However, in large generators, these wires are replaced with copper strands roughly 2mm by 5mm or so, which are then bundled into groups of 100 or more in a rectangular shape. Usually, the resistance losses are such that air or hydrogen cooling is enough. However, when you start pushing around thousands of amps, even very small resistance losses turn into a lot of heat. At a certain point when you are making a generator larger and larger, all that copper becomes prohibitively expensive.

    The first thing to do is replace the air with hydrogen. Hydrogen has less cooling capacity, but it is far less dense than air so the air friction of the rotor is much less, resulting in less heat. In truly large machines, however, that isn't enough. Above around 350MW, you make a portion of these copper strands hollow and pump water through them.

    The combination of water, thousands of amps, and hydrogen sounds pretty dangerous, and you would be right in thinking that a lot of machines went BOOM before they nailed all the potential problems. One problem though remains the chemistry of the water in the copper strands. Demineralized, oxygen-free water is generally used, along with oxygen-free 99.999% pure copper. If a large amount of oxygen is in the water, there start to be buildups of gunk in the tiny strands, which can not be cleaned mechanically. You can search "oxygen in stator cooling water" on google and get a few articles. The only way to clean it is with an acid wash, and engineers get nervous about this because if you clean out all the gunk, invariably you have also caused material loss of your copper.

    Which brings me in a very roundabout way back to San Onofre. They did everything right, but kept getting gunk in their copper strands. No oxygen in their water, and the water conductivity was more than high enough (sufficiently pure). And yes, they did check to make sure that water measurements were correct. Nevertheless, they were needing to acid-clean their generator stator copper strands every 2-4 years, which is alarming considering that the average machine only requires such acid cleaning between 0 and 2 times in a 40 year lifespan. Nobody has ever required this much acid cleaning, so the point at which the copper strands become too eroded by the acid is not clear. I'm sure some regulator was watching this very closely because of the huge disaster a water leak can have.

    The only way out of this mess would have been be a new stator, or a rewind. A stator of that size weighs more than can not be transported in once piece, since it weighs at least 2 million pounds (no exaggeration). Building it or rebuilding it on site costs tens of millions of dollars just in labor and windings, not to mention all the lost generation.

    This electrical generator problem certainly didn't sink San Onofre by itself, but it didn't help things either. I suspect there were a few other issues which would require a huge investment of money at a time when California is broke, the utility has a hard time getting a rate increase, and natural gas is cheaper than it has ever been in the US (there are basically 0 operating coal plants in California, although there are some just across state lines which sell exclusively to California). It probably would be cheaper in the long run to repair and refit San Onofre, but when money is tight, short term solutions take priority.

Things are not as simple as they seems at first. - Edward Thorp