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New Threat To Seaside Nuclear Plants, Datacenters: Jellyfish 123

Nerval's Lobster writes "One of the largest nuclear-power plants in the world was forced to shut down temporarily Sept. 29, after pipes that bring Baltic Sea water in to cool the plant's turbines became clogged with tons of jellyfish. The sudden influx of common moon jellyfish overwhelmed the screens and filters that keep flotsam and most sea life out of the Oskarshamn nuclear plant in southeastern Sweden. The plant was forced to shut down its No. 3 reactor – the largest boiling-water reactor in the world, which generates 1,400 megawatts of electricity when it is jellyfish-free and running at full power. The reactor stayed down until early Oct. 1, after the jellyfish had been cleared out and engineers approved the cooling system as invertebrate-free. It's not easy to overwhelm the cooling system for a nuclear power plant, but Oskarshamn's is unusually resilient. There is a separate intake- and cooling system for each reactor, all of which were designed for the brackish, polluted water in that area of the Baltic Sea. Most datacenters are too far inland to worry about jellyfish in their cooling water, though green-IT-promoters Vertatique estimated that a 5,000-sq.-ft. datacenter would consume almost 9 million gallons of water for cooling. That means ocean-side datacenters that use sea water for cooling (such as Google's datacenter in Hamina, Finland — also on the Baltic Sea) are just as susceptible to jellyfish attacks as nuclear power plants."
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New Threat To Seaside Nuclear Plants, Datacenters: Jellyfish

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  • Do they have 3 eyes?

  • by N0Man74 ( 1620447 ) on Tuesday October 01, 2013 @05:50PM (#45008313)

    I guess we'll need a Geiger counter to figure out if they have a natural bioluminescent jellyfish glow, or if they are irradiated.

  • Rampant Jellyfish (Score:5, Interesting)

    by StoneyMahoney ( 1488261 ) on Tuesday October 01, 2013 @05:54PM (#45008359)

    There's been a huge increase in the jellyfish populations around the world, they've been thriving as the seas warm up - more plankton equals more jellyfish. Fishing boats are catching huge nets of the things when they're supposed to be picking up fish. It's such a problem, there's a Japanese effort to get people to eat jellyfish sushi.

    • by Anonymous Coward on Tuesday October 01, 2013 @05:58PM (#45008413)

      If an "effort" is required to get Japanese people to eat something that comes out of the ocean, you really don't want to go near it.

      • Re:Rampant Jellyfish (Score:4, Informative)

        by Trane Francks ( 10459 ) <> on Tuesday October 01, 2013 @08:24PM (#45009759) Homepage

        If an "effort" is required to get Japanese people to eat something that comes out of the ocean, you really don't want to go near it.

        Kurage (jellyfish) have featured in the Japanese diet throughout history. There is no "effort" of which I'm aware, and I've been in Japan since 1991.

        • Re: (Score:2, Funny)

          by pspahn ( 1175617 )
          As long as your kid's apathetic teacher isn't banging the chef, I suppose things will be okay.
        • As Foghorn Leghorn said "That's a joke, son. A flag waver. You're built too low. The fast ones go over your head. " The point was that the Japanese don't need to be forced to eat the deadly pufferfish or whale (most people think the meat sucks and it's only a small group of nut jobs who actually like it),and if it takes effort to make them eat something, yeah, you don't want to go near it. It was just a joke.
          • Yes, I'm fully cognizant of the nutjob whale lovers (tried it at my MiL's and nearly vomited) and the danger of fugu (tried it and managed not to die). The joke failed on the "if it takes effort" part. It would have been funny were there any effort being made to promote it; in the absence of any effort, there's also an absence of requisite irony.

    • by gtall ( 79522 )

      So....the jellyfish are the global warming's answer to overfishing of the oceans. That's sublimely wonderful.

    • more plankton equals more jellyfish

      Really? I thought more plankton equals more fish and whales. Unfortunately since we've decimated fish stocks worldwide, more plankton equals more jellyfish. Many fish are happy enough in warmer seas, it's the giant nets strewn everywhere that they have a problem with.

      • by GNious ( 953874 )

        Shouldn't we then see an increase in those species, that eat jellyfish?

        Some of the most common and important jellyfish predators include tuna, shark, swordfish, and at least one species of Pacific salmon, as well as sea turtles, also known as leatherback turtle. []

        • Shouldn't we then see an increase in those species, that eat jellyfish?

          Well let's review the list you pointed out:

          Some of the most common and important jellyfish predators include tuna,

          We eat them. A lot. In fact we fish them so much that we tend to accidentally fish nearby dolphins too.


          We eat them. Not only that, but we are at a slaughtering rampage against them, because once in a blue moon a careless human happens to be killed by one.


          We eat these too.

          and at least one species of Pacific salmon

          We eat these a lot. They end up in sandwiches almost as frequently as thuna.

          as well as sea turtles, also known as leatherback turtle

          We occasionally eat sea turtles too, at least the few surviving which haven't yet choked up on plastic bags or similar ga

    • "There's been a huge increase in the jellyfish populations around the world, they've been thriving as the seas warm up"

      Or is it as overfishing grows?

      • Re:Rampant Jellyfish (Score:5, Informative)

        by qubezz ( 520511 ) on Wednesday October 02, 2013 @08:51AM (#45012731)

        It's estimated that now over 50% of the biomass of the world's oceans is jellyfish, in some cases completely displacing all other biosystems. One other human activity vector that has impacted jellyfish populations is shipping, transporting species globally to locations with no predators. The warming of waters by nuclear power may locally cause phenomenon which encourage jellyfish growth also. If you could avoid destroying other marine life, maybe the answer to the cooling intakes is "will it blend?".

        Japan’s nuclear power plants have been under attack by jellyfish since the 1960s, with up to 150 tons per day having to be removed from the cooling system of just one power plant.


        That’s just what happened when the Mnemiopsis jellyfish (a kind of comb jelly) invaded the Black Sea. The creatures arrived from the east coast of the US in seawater ballast (seawater a ship takes into its hold once it has discharged its cargo to retain its stability), and by the 1980s they were taking over. Prior to their arrival, Bulgaria, Romania, and Georgia had robust fisheries, with anchovies and sturgeon being important resources. As the jellyfish increased, the anchovies and other valuable fish vanished, and along with them went the sturgeon, the long-beloved source of blini toppings.

        By 2002 the total weight of Mnemiopsis in the Black Sea had grown so prodigiously that it was estimated to be ten times greater than the weight of all fish caught throughout the entire world in a year. The Black Sea had become effectively jellified. Nobody knows precisely how or why the jellyfish replaced the valuable fish species, but four hypotheses have been put forward.

        from []

    • Re:Rampant Jellyfish (Score:5, Interesting)

      by ColdWetDog ( 752185 ) on Tuesday October 01, 2013 @09:54PM (#45010243) Homepage

      We have been seeing ** lots ** more jellyfish the last several years in SE Alaska. This summer we kayaked through a half kilometer long field of them. Very, very trippy but fisherman absolutely hate them. You can't get them to move. If you net them you can't get their slimy bodies off the net. Nothing local eats them very effectively. Shooting at them with a shotgun doesn't do much except waste ammo and scare tourists.

      • by Anonymous Coward

        Well, there used to be local predators - but we ate them.

        Or with less humour, jellyfish has predators at all stages - however since it mainly is turtles (tasty) and whales (tasty, blubber) the predators are in decline.

        To further the problem one of the more effecient ways to keep jellyfish under control is simple starvation - but that requires other animals that eat fish and plankton (which means lots of tasty whales and tasty fish are needed).

        And even nastier are that some jellyfish releases their reproduct

      • by AlecC ( 512609 )

        I love the way Americans turn to guns to solve any problem. To bear arms - against jellyfish!

    • by DrXym ( 126579 )
      Maybe someone needs to figure a way of turning jellyfish into energy.
    • Does more plankton also implies more fish?
  • by Anonymous Coward on Tuesday October 01, 2013 @05:57PM (#45008389)

    Jellyfish attack?

    attack [uh-tak]
    verb (used with object)
    to set upon in a forceful, violent, hostile, or aggressive way, with or without a weapon; begin fighting with: He attacked him with his bare hands.
    to begin hostilities against; start an offensive against: to attack the enemy. ...

    Kind of implies a certain amount of forethought and/or planning. If jellyfish attacked the cooling system then I have a newfound respect for the intelligence of jellyfish.

    Perhaps they simply infested the cooling system? Editors, they aren't just for breakfast any more.

  • We have the world's largest jellyfish here in Puget Sound.

    Remember, jellyfish are smarter than Congress. Not that that's hard to do.

  • by Anonymous Coward

    I remember reading about power plants having this issue back in the '90s.

    • by turgid ( 580780 )

      I remember reading about power plants having this issue back in the '90s.

      I worked at a nuclear power plant back in the 90s and we did indeed have trouble with jellyfish in the cooling water (also old tyres, shopping trolleys, plastic bags, nudey books, the bodies of foreign migrant workers...). It's not unique to nuclear power plants and it's been an issue since the first power station to use see water for cooling.

      The other thing was prawns growing inside the condensers under the steam turbines. Every few

  • by willy_me ( 212994 ) on Tuesday October 01, 2013 @06:12PM (#45008537)

    Does it not make more sense to use clean, filtered water to transfer the heat out into the ocean? The heat exchanger can sit in the ocean to facilitate removing heat without the worry of having jellyfish clogging filters. Effective cooling capacity might be reduced without an active water stream going over the heat exchanger, but this can be compensated for by using a larger one.

    The only possible problem I can see is the build-up of aquatic life on the head exchanger. They would require periodic cleaning. But unlike filters, you would not have to shut down the cooling system to do so. In addition, you don't have to worry about there being any sudden changes in the cooling capacity of the system so it should be much easier to plan and perform the cleaning.

    • This idea makes far too much sense for anyone to ever implement it.

      • My god, the smugness of back-slapping armchair engineers can be incredible.

        OK, my smarty pants, you come up with a feasible design which can dissipate 2GW thermal in a reasonable amount of space. Don't forget that you have to be able to fit in all the reactors for this power station, not just this one.

    • by Anonymous Coward on Tuesday October 01, 2013 @06:47PM (#45008937)

      Mineralization is a big problem with that. It's easier to deal with mineralization (as well as having better heat exchange) by having a high flow rate at higher pressures, and that's done by pumping water in through piping. In industrial plants it's also not about volume, but more about mass flow rates, the mass is what moves heat around and a simple radiator typically doesn't cut it.

      Of course they could do like most shipboard steam plants do and have some design in the plant that allows for a valve line-up that lets you purge the intake. More or less, it's a method of temporarily reversing the flow. (It's nowhere near efficient, but if you're blowing steam or pumping high pressure water out the intake, most typical flotsam and jetsam goes bye-bye. Anything that doesn't get requires a tear-down and/or divers.) Some steam powered ships also have more than one intake so they can be alternated for servicing, which is a nice redundancy feature.

      It's been some years since I dealt with a little bit of that stuff, so I may be a bit fuzzy on it, but if you asked a plant operator I'm probably not too far off the mark.

    • by aaarrrgggh ( 9205 ) on Tuesday October 01, 2013 @07:13PM (#45009199)

      Heat transfer is proportional to the temperature difference between the return water and the surrounding (approach temperature), the surface area, and the thermal conductivity of the medium. Higher temperature differences reduce the thermodynamic efficiency, and fouling of the heat exchanger is going to reduce the thermal conductivity, as will the thicker metal that will withstand the corrosion. You also need to deal that without inducing water flow across the heat exchanger you are going to get stratification of warmer water and further reduce heat transfer.

      But, the problem has been solved for a long time. In Hong Kong they use harbor water to run through the chillers for cooling buildings. You can't possibly get worse water than that no matter how hard you try. It takes a lot of maintenance and multiple stages of filters, but it works pretty well.

      • by Anonymous Coward

        In Hong Kong they use harbor water to run through the chillers for cooling buildings. You can't possibly get worse water than that no matter how hard you try.

        I have some reservations about that. Highly polluted, yes, but also devoid of jellyfish, or any marine life for that matter, might make it easier to filter!

        • Jellyfish abound in HK harbor. About the only living thing there; they seem to thrive on pollution.

    • It's probably an issue of cost. I'm shooting from the hip here, but I think you'd still need a heat exchanger inland so that in case of a radioactive leak, your last line of defense isn't the heat exchanger out in the salt water. So now you have two heat exchangers instead of one. And the big one in the salt water is going to be murderous to service unless you had some way to raise it up out of the water, which would of course add a lot of cost. Salt water is incredibly rough on anything - you try not to to

      • by mrvan ( 973822 )

        Look at it this way: you can't really put the heat exchange out in the ocean without any protection, since you really don't want a trawler, submarine, or whale disrupting the cooling of your nuclear plant. So in effect you will be building a contained heat exchange in the ocean, which will have some sort of intake, which can be clogged.

        Also, the water needs to flow to bring cold water to the heat exchange. While the convection will cause some flow, powered pumps can make a lot more flow. And pumps by necess

  • Ah, jellyfish. This is one of my favourite up-and-coming ocean doomsday scenarios.

    - No hard parts, so unaffected by ocean acidification
    - Perform well in anoxic (low oxygen) environments
    - Eat everything
    - Have almost no nutritional value of their own
    - Can shrink when food resources are low, and simply eat less
    - Few natural predators
    - Some species are effectively immortal by way of reverting to earlier life stages

    To a certain extent, it's a bit of a miracle that the oceans managed to ever keep them in check, but oxygenation of the oceans created whole ecosystems of creatures that could--as a group--effectively compete against jellyfish.

    There's no one predator that we can release that will keep the jellyfish contained or under control. It takes whole ecosystems to combat a real jellyfish problem.

    Here's a review of a book written by Dr. Lisa Gershwin (composer Gershwin's granddaughter, I believe) []

    Fortunately, humans are adept at obliterating species if they can get a taste for them. Better acquire a taste for them quick.

  • THe issue is the screen before the intake is clogged right?

    Okay... what about another screen well away from that one with a much larger surface area...

    That fixes the problem right? Right... okay. Do that.

    • by mirix ( 1649853 )

      No, that's all wrong. They need to make the screen sharper.

      Then the reactors will be cooled with jellyfish puree. I'd imagine that would have a similar specific heat to water.

    • by blippo ( 158203 )


      As the spot prises go UP when they have to shut down a large part of the total production capacity,
      then they may actually make more money from their other plants when that happens.

      So there's not exactly any incentives to go check the intake filter too often...

  • I live 1.3km from salt water. Late in the quiet of the night I hear a distant thrumming, "we're coming we're coming we're coming we're coming......"
  • Not new (Score:5, Informative)

    by zmooc ( 33175 ) <(zmooc) (at) (> on Tuesday October 01, 2013 @06:42PM (#45008877) Homepage
    • by Tailhook ( 98486 )

      That's what I thought when I read the summary. Water intakes have been getting plugged up with all sorts of schooling critters forever. I've read at least a dozen NRC reports about everything from seaweed to beaver dams interfering with power plants.

      Our infrastructure just isn't as fragile as gullible office people seem to wish it were. Jellyfish aren't going to revert us to yurts and hobby farms anytime soon. Sorry.

    • Re:Not new (Score:5, Insightful)

      by Vitriol+Angst ( 458300 ) on Tuesday October 01, 2013 @10:06PM (#45010295)

      "A quick google comes up with at least 5 similar incidents in 2011 and 2012."

      I don't think "not new" means what you think it means.

      • by zmooc ( 33175 )

        Fine. Here a's discussion about similar events in 2005. []

        I repeat: this is not new. It's just that the older news - including the article referenced in my link above - has disappeared from the interwebs.

        • We've had nuclear power plants for 40 years or so, and sea water cooled installations for a lot longer than that. Stuff coming up in the last 10 years is still fairly new to developed industries. I realise that a lot of people here are more used to the technology sector where 2 years old is so old you wouldn't even consider it, but heavy industries operate on a much slower time scale.

  • The new way breach a datacenter.....

  • by Dr.Dubious DDQ ( 11968 ) on Tuesday October 01, 2013 @06:55PM (#45009017) Homepage

    It amuses me that the collective noun (you know, like a "pack" of dogs or a "flock" of birds or a "tantrum" of Representatives) for jellyfish is a "smack".

    It's like you can just hear them smashing themselves into water intakes. "SMACK!".

    We now return this thread to people with more directly relevant things to write.

    • by gsslay ( 807818 )

      90% of collective nouns are made-up bullshit only ever referenced in quizzes and "Did You Know" observations. No-one uses them in actual conversation, ever.

      In my book that not only makes them Useless Knowledge, but also Fictional Knowledge.

      • I'm surprised you're the only one saying this. I kind of expected an entire kvetch of slashdotters to make the same complaint.
        • by gsslay ( 807818 )

          We had a meeting and I was appointed "Derider of the Collective Noun". So I'm filling in for the entire kvetch.

  • Not bad for 100 years of service.

    Per second?

    Who knows.

    It will also use 2 liter. Or possibly a library of congress.

  • Have a giant fan with blender blades in front of the intakes. It might be cruel though, so that may be a bad idea. Doesn't sound very humane or jellyfishane .. i am sure there are other ways to deter jellyfish.

    • Re:Blender blades (Score:4, Interesting)

      by InvalidError ( 771317 ) on Tuesday October 01, 2013 @08:56PM (#45009937)

      Considering how much of an invasive species jellyfish are, drastic measures to get rid of them might become necessary and "raw jellyfish in, cooked jellyfish out" might end up not being such a bad thing.

      One thing some water treatment plants do is put a conveyor mesh in front of intakes. Jellyfish and other solids get tangled in the mesh, lifted as the mesh rotates, gets scraped off and dumped with solid waste. If they do not care about cleaning up solid waste in the water, they can dump the intake's catch in the return stream.

  • So remind me, how is this news? They would have known about the possibility of this happening from the day the plant was designed.

    Fish blocked the intakes? Shut the reactors down.

    Wait what?! That's exactly what happened!? Well holy mackerel it worked as intended.

    This is a FUD piece designed to sway people from nuclear energy. Nothing more. Does it really belong here on /.?

  • To be fair, this issue could easily affect any sizable power plant, nuclear or fossil. Giant coal-fired boilers also typically use nearby bodies of water to cool their condensers, same as a nuclear plant. The sensationalist "threat to nuclear plant" bit in the title is a bit overmuch.

  • This was already the subject of a WANO (World Association of Nuclear Operators) Significant Operating Event Report a few years ago - something to do with loss of heat sink. All nuclear stations worldwide will have a credible and audited plan to deal with this by now. Jellyfish does make a good headline, though,
  • Any reports of a blue glow in the deeps?

  • It was a steamship problem and then a coastal coal fired power station problem.
  • Just remove the screens and let em all through; maybe add a macerator. Anyone happen to know offhand the thermal coefficient of jellyfish jelly?
  • A horde of jellyfish-like animals has forced the shutdown of a nuclear power plant in California.
    The gelatinous creatures, 2 to 3 inches long, are called sea salp. []

    Sea salp can reproduce sexually and asexually, and "you can have millions in a couple of days," e []

    Actually jelly fish took down a California reactor many years ago but 1912 (the ab

  • by Terje Mathisen ( 128806 ) on Wednesday October 02, 2013 @03:37AM (#45011553)

    A few years back we were sailing on my father-in-law's nice sloop when the wind dropped so we had to start the engine.

    At the time we were in the middle of the narrow Drøbakssundet sound which all shipping to/from Oslo has to pass through, so we had to get out of the shipping lanes quickly, right?

    After just a minute or so the engine choked up, and with a dead calm we had no other option than to declare an emergency and use the VHF to call for assistance from Sea Rescue.

    We got towed into harbour and lifted up, then we found that the cooling water intake had got clogged by jellyfish puree. :-(


  • There's so much water in those jellyfish that they can be processed through a mixer / blender to make a jellymilk.
    The cooling pumps and tubes could be adapted to this fluid a little bit thicker than water.

The absent ones are always at fault.