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Nuclear Plant Taken Down In Anticipation of Snowstorm

Posted by samzenpus on from the too-much-to-shovel dept.

mdsolar writes Pilgrim Power Plant in Plymouth was taken offline in anticipation of the weekend snowstorm. According to a statement from Entergy, the owner of Pilgrim, the plant was taken off line in preparation of "a potential loss of offsite power or the grid's inability to accept the power Pilgrim generates." This is the second time this season the plant has been shut down due to storm conditions. On January 27 the facility was taken offline after the two main power transmission lines were knocked out by blizzard conditions. Although the transmission lines were restored within a few days, the plant remained offline until February 7 at which time it was reconnected to the grid.

24 of 311 comments (clear)

  1. A precaution when done ahead of time. by Anonymous Coward · · Score: 5, Insightful

    An emergency measure when done after the fact.

    1. Re:A precaution when done ahead of time. by Mr+D+from+63 · · Score: 4, Interesting

      The plant will be shut down in anticipation that the transmission grid will suffer problems and not be able to take the power. It has nothing to do with the plant itself or inability to run through the storm. Plants all over the northeast have kept the lights on for millions throughout that rash of harsh winter weather we have been having. Pilgrim is a reliable station still going strong after many years.

      Snow covered solar panels won't be very useful, that is for certain. Windmills are shut down in blizzard conditions. Thankfully other sources are available.

    2. Re:A precaution when done ahead of time. by Rei · · Score: 4, Interesting

      "Potential loss of offsite power" was listed as one of the two reasons for taking it down; the inability of the grid to accept power is only one. I would presume based on this that offsite power is part of their scenario for dealing with emergencies wherein the plant can no longer supply power for cooling its reactor, and hence the risk of loss of offsite power means an unacceptable meltdown risk should a disaster occur at the plant in the coming days.

      --
      We gotta go to a crappy town where I'm a hero.
    3. Re:A precaution when done ahead of time. by Mr+D+from+63 · · Score: 4, Informative

      True.

      Loss of offsite power is an analyzed condition and the plant's license requires it to shut down when offsite power is lost. The safety analysis shows that the plant is in a higher risk level as it becomes reliant on its emergency diesels should another severe accident occur at that time. (Even though in those situations, the plant is designed to still be able to cope with all design basis accidents)

      There is no license requirement to shut down in anticipation of a loss of offsite power, and the plant is designed to handle it safely.

      Plants keep running through major storms all the time. This is particular to the local grid.

    4. Re:A precaution when done ahead of time. by Mr+D+from+63 · · Score: 3, Informative

      I'd like to correct my statement above which says "There is no license requirement to shut down in anticipation of a loss of offsite power".

      Actually, there is a generic requirement to monitor grid reliability, and an unreliable grid determination could force a licensee to shut down. That is typically based on actual performance, not on anticipation, but I wanted to be accurate.

    5. Re:A precaution when done ahead of time. by TubeSteak · · Score: 4, Informative

      Pilgrim is a reliable station still going strong after many years.

      Lol @ reliable. Pilgrim has been on the NRC's worst-ten shit list for a few years now.

      The same day the storm hit, the NRC sent Pilgrim a letter.
      http://pbadupws.nrc.gov/docs/ML1502/ML15026A069.pdf

      Overall, the NRC has determined that your act ions have not provided the assurance level to fully meet all of the inspection objectives and have correspondingly determined that Pilgrim will remain in the Degraded Cornerstone of the Action Matrix by the assignment of two parallel White PI inspection findings. [Green, White, Yellow, Red, in increasing order of severity] [...] . Additionally, for one of the
      root cause evaluations, inspectors determined that Entergy failed to investigate a deficient condition in accordance with corrective action program (CAP) requirements to ensure they fully understood all of the causes of one of the [four unplanned] scram events [that happened in 2013].

      Reliable != multiple unplanned SCRAMs per year.

      Anyways, on January 27, while the reactor was SCRAMing, these three things happened:

      The High Pressure Coolant Injection System had to be secured due to failure of the gland seal motor.
      The station diesel air compressor failed to start.
      One of the four safety relief valves could not be operated manually from the control room.

      Those safety relief valves are the ones that get used to vent pressure after the coolant injection system fails.

      Pilgrim has problems. On top of all those problems, locals are spitting mad because the disaster plans fail to include scenarios like "giant blizzard shuts down all the roads and nobody can evacuate."

      --
      [Fuck Beta]
      o0t!
    6. Re:A precaution when done ahead of time. by Luckyo · · Score: 3, Insightful

      The primary cause was the failure of backup generators that got flooded by the tsunami. Earthquake was actually not a problem - it didn't damage anything crucial even though it was a hundred times more powerful than what plant was built to withstand. Secondary cause was loss of all regional infrastructure, including loss off off-site power, loss of ability to easily access to plant to get replacement power from mobile generators and other similar problems related to logistical difficulty of trying to get cooling when entire region is devastated with over 30.000 dead and hundreds of thousands displaced due to the massive flood. They had the plans, but having no easy access to anything in the region due to the massive flood made those plans impossible to implement.

    7. Re:A precaution when done ahead of time. by AmiMoJo · · Score: 4, Informative

      Actually the earthquake damaged part of the emergency cooling system and thus prevented effective cooling that would have averted a meltdown. This did not become apparent until months after the disaster when it was possible to examine the pipes and valves that make up the system. They were pumping water in with fire engines, but it was being syphoned off by a broken valve and never made it to the reactor. Even if the valve had been okay, pipes further down were leaking anyway.

      Search YouTube for NHK documentaries on the subject. NHK is like the Japanese version of the BBC, pretty reliable and they have done a lot of work examining what went wrong at Fukushima. Their documentaries are available in English.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
  2. mdsolar strikes again by peon_a-z,A-Z,0-9$_+! · · Score: 4, Insightful

    He probably wouldn't post something about a 'renewable' going offline, based on his posting history.

    1. Re:mdsolar strikes again by Mr+D+from+63 · · Score: 4, Informative

      Nothing that mdsolar wrote was untrue, and it didn't even sound judgemental.

      To be fair, the title was changed by samzenpus. mdsolar's submittal title said something like "unreliable nuclear plant shut down....". An attempt to mislead on the reason for the shutdown.

    2. Re:mdsolar strikes again by AK+Marc · · Score: 3, Insightful

      If the wind is that high, the snow won't collect on the solar panels that easily. It drifts off of high places, like roofs, and collects at fences and other things that catch the air. The stated combination won't happen as needed for the AC horror scenario to happen.

      --
      Learn to love Alaska
    3. Re:mdsolar strikes again by Tailhook · · Score: 5, Informative

      You are attempting to discredit this story by maligning the submitter.

      The story is FUD. That's mdsolar's MO; post transparently stupid, fear mongering stories about nuclear power. He deserves to be maligned; he's earned it.

      --
      Maw! Fire up the karma burner!
    4. Re:mdsolar strikes again by OhPlz · · Score: 3, Informative

      The snow is light-weight powder and we haven't had a thaw/freeze cycle, so when the wind hit makes no difference. Only about half of the roofs have been flat. There's a huge multi-building apartment complex down the street from me that evacuated because one building did have a roof collapse. The roof was nearly as pitched as my own. A number of others in other towns with similar style roofs have had the same problem.

      Wind can relocate snow, but high wind doesn't mean roofs or anything else gets cleared off. It just means the snow gets put wherever nature feels like it. Get some gloppy slushy snow and that stuff will stick to anything like glue. Your panels would be doing about as good as our roofs, which isn't very good. The best part is that houses with panels would have to bear the weight of the roof, the weight of the panels, plus the weight of the snow. Not to mention the wind when it really gets ripping up here will want to tear those panels right off. Wind gets strong enough here to remove roofs if there's enough imperfection in them, or shoddy maintenance, or stuff attached to them that wasn't meant to be there.

    5. Re:mdsolar strikes again by OhPlz · · Score: 3, Funny

      It was windy the whole time. But what the fuck would I know, I just live in the area.

  3. Re:The U.S.A. is now a third world country by Anonymous Coward · · Score: 5, Informative

    If such a thing happened in Canada you can be sure we wouldn't take over a week to repair the government-owned power lines.

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

    Right...

  4. Re:Devil's advocate of the Devil's advocate? by peon_a-z,A-Z,0-9$_+! · · Score: 4, Insightful

    However, in this case, the customers don't lose power because the generation isn't there. Customers would lose power because the grid fails. Entergy has power from other sources or purchasing agreements to make up for this temporarily.

    Similarly, it is unsafe (and illegal, technically) to run your nuclear powerplant with no access to the grid. If you have a coal plant that gets disconnected from the grid, you'd shut it down too with no way to generate revenue from burning additional fuel.

    Devil's advocate to your misguided devil's advocate...The problem is the electrical grid not the source.

  5. Nuclear plants don't like sudden shutdowns by ZombieEngineer · · Score: 3, Informative

    Sounds like this is a "preventative measure".

    Normally there is some time between neutron capture and actual nuclear fission (I have heard a figure of 15 minutes). This means that even if the control rods are slammed in when the power transmission lines were cut the previous heat load would still be generated for a period of time. Often this means resorting to drastic measures to reduce the neutron flux to zero ASAP (certain salts are added to cooling loops which achieve this but requires a good flush to get rid of).

    Controlled shutdown means the reactor can be restarted in "a couple of hours"
    Emergency shutdown means the reactor can be restarted in "a couple of weeks"

    Burnt once, twice shy...

    1. Re:Nuclear plants don't like sudden shutdowns by AK+Marc · · Score: 3, Interesting

      Yes, that was the problem with Fukushima. The design guaranteed a meltdown in the case of loss of power. If you lost mains power, and your generator didn't start, you have a 100% chance of a meltdown. The tsunami took out the mains and the generators. So a meltdown was guaranteed, because they didn't restore power. Nothing else matters from that point. If they had requested a generator and fuel from someone and gotten it in the 12 or so hours the batteries lasted, then we'd know for sure whether the loss of containment was guaranteed by a breach caused by the earthquake. But Japan never asked, so nobody even tried.

      I'd assume that the plant in question is of a similar design.

      What I'd do is that because a meltdown makes more than enough power for a secondary, smaller generator to make enough power to prevent a meltdown. Sort of an active-verson of a passively cooled reactor. But cost and liability are more important than safety.

      --
      Learn to love Alaska
    2. Re:Nuclear plants don't like sudden shutdowns by AK+Marc · · Score: 4, Interesting

      Since you bought up Fukushima, I've long wondered how a modern first world nation-state could not manage to get generators on-site before the batteries went flat. I've read that the utility tried but could not get them there in time due to traffic jam and destroyed infrastructure on the ground. Did nobody think of picking up the phone and calling someone at the military to dispatch some bloody helicopters? I can't fathom that you need so much power to run cooling pumps as to render the required generators too heavy to fly in.

      I didn't want to say, because it sounds like the "depend on the US" cliche, but I could have driven to work, chained up a generator (not sure what they needed, but I had a 40kVA that I could have sent), and driven it to a C130 (nearby military base) and gotten it on the ground in Japan well under the 12 hours battery they had (presuming the US military would give civilian aid). Then arrange some helicopter transport to the site.

      My understanding is that Tepco lied to everyone. They lied about it being under control, and whether it would be "saved" and what they needed and such. An international call for generators, and I'm sure there are hundreds (or thousands) that could have come from South Korea in time, even if they couldn't find a single one in Japan. And there would have been many options to getting it there. Tanks don't mind mud so much, and you can hook a civilian trailer to one. So tow the damn thing. On the road, where you can, on the shoulder where you can, over fields and through houses where you have to. It's a fucking nuclear meltdown.

      But Tepco said "it's under control". "There was an incident, but it's currently contained". At least that's how I understand it from the information I saw released. Everyone with a "C" in their job title should be in jail, or working from the reactor floor.

      --
      Learn to love Alaska
    3. Re:Nuclear plants don't like sudden shutdowns by angel'o'sphere · · Score: 3, Informative

      What you write is complete nonsense.

      There is no 'neutron capture' taking 15 minutes.
      Either it smashes an uranium atom, that is called fission, or it is captured by boron ...

      There is absolutely no difference if a reactor is shut down by emergency or 'controlled'. If it is down longer than 30 mins, the time to reactivate it is days. The reason is neutron poisoning ... or xenon poisoning, depending how you want to call it.

      That means, the decaying products of the fission reaction produce so much Xenon and Boron that the neutrons of an start attempt get captured by them. Hence a new 'controlled' fission reaction is not possible, until those elements decay further.

      That takes hours, up to days. This is the main reason why nuclear plants can only be used very limited for load following (if you power it down considerably, you have to make sure you either don't need it full powered soon, or you know you will power it back up VERY soon)

      --
      Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
    4. Re:Nuclear plants don't like sudden shutdowns by AmiMoJo · · Score: 3, Interesting

      See my other comments, generators were available but would not have helped. In fact they had extra pumps attached and working, but it didn't do anything.

      TEPCO were confused due to the difficult situation on the ground, and didn't want to start doing press released for every bit of data that came in and creating a lot of wild speculation in the media. The surrounding area had already been evacuated and as I mentioned there was little anyone could have done to help, so there wasn't much point saying anything until they were certain.

      It was still badly handled of course, but there was also a genuine belief that things were not that bad due to flawed operating procedures. Much of the monitoring equipment had failed due to lack of power and earthquake/tsunami damage, so the plan to make manual readings was put into place. That was hampered by lack of access to critical areas due to high radiation and damage to the plant. The procedures were written with the assumption that data could be relied on and that a lack of data was not a cause for action or assuming the worst. Note that TEPCO didn't write the procedures, they were standard on that type of plant.

      Sticking to procedure is viewed as best practice in many industries. For example, on the bullet trains the drivers are taught to always refer to the manual. If there is any kind of fault they never rely on memory, they always open the manual and follow it step by step. They actually read out each step as they are doing it. That helps prevent mistakes, and so far they have an unblemished safety record with zero deaths or serious injuries despite constant operation since 1964. Clearly, it is less suitable for nuclear plant operation.

      Basically, this is the problem with most current plants. If something goes wrong it is hard to understand what is happening, and even with experts on hand a lack of data leads to bad decisions and mistakes.

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
  6. MDSolar must be disappointed... by dfenstrate · · Score: 4, Insightful

    ...that it didn't melt down. We get it, MD, you don't like nuclear power.

    --
    Alcohol, Tobacco and Firearms should be the name of a store, not a government agency.
  7. Re:strange circumstance. by peon_a-z,A-Z,0-9$_+! · · Score: 4, Informative

    Nuclear plants of the design mentioned in the article must legally have offsite power to continue operation. As soon as offsite power is lost, the plant is required to shutdown. An emergency shutdown is more paperwork than a planned shutdown such as this.

    The reason for this is that in an accident scenario, you would like to rely on offsite power to run your emergency coolant pumps for this particular design.

    Newer reactor designs don't have this issue, but this is a pretty economic decision considering an emergency shutdown if/when the offsite power does eventually trip. The grid seems pretty unreliable based on past experience, as the article even notes.

  8. Re:The U.S.A. is now a third world country by dbIII · · Score: 3, Interesting
    Maybe taking advantage of the shutdown to do a bit of inspection and maintainance turned up something that took a while to fix. I'm sure a few people on this site have experience of a server that had been on for over a year with no problems but would not power back on after a full shutdown and cold start. Mechanical systems can act that way as well, especially if there is a bit of heat involved and the size difference between parts when cold or in operation is significant.
    I've seen a wide variety of broken components in even well run thermal power plants (I've never worked with nukes but anything after the water is heated is pretty similar). I've seen even more on the way to breaking and getting cut out before they can fail.
    So to sum up I don't think there's much to take away from a single outage - if all you've got is outage times you'd have to get statistical with more info before a sensible judgement.

    I went through the ice storm of 98 - a month with no power. 25 people died of hypothermia.

    A month and a serious death toll, that does indeed suck. I'd wonder why they didn't truck in a pile of the container sized generators or a similar disaster plan as done by utilities after hurricanes.