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Reactor Shutdown Darkens South Florida 356

grassy_knoll asks, "So how fragile is the electrical grid, and just what technical problems could shut down five reactors?" "Five reactors at a nuclear power plant in Florida had gone down on Tuesday and two were now back online amid a massive power outage in the southern state, CNN reported. The report on the Turkey Point nuclear plant came as four million people had lost electricity in Miami and elsewhere in Florida, with traffic signals out and major delays on roads, authorities and media said."
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Reactor Shutdown Darkens South Florida

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  • D'oh (Score:4, Funny)

    by longacre ( 1090157 ) * on Tuesday February 26, 2008 @07:51PM (#22566418) Homepage
    I hear the problem originated with a drone in sector 7-G.
  • by Penguinisto ( 415985 ) on Tuesday February 26, 2008 @07:52PM (#22566428) Journal
    ...I never knew Florida had a town named Springfield.


  • Here is FPL's page on the Turkey Point reactor: About Turkey Point []. Their site also has a News Releases [] page, which I'll be watching for updates whenever they get their PR department in gear.
  • by xC0000005 ( 715810 ) on Tuesday February 26, 2008 @07:55PM (#22566470) Homepage
    Oh, wait. This is Florida. Things already look like a Mad Max movie, minus Tina Turner and with a lot more cubans.
  • by Anonymous Coward
    Now we're going to have yet another round of computer scientists and other pseudo-engineers telling us how they would have done it better.

  • 5 reactors? (Score:5, Informative)

    by drachenfyre ( 550754 ) on Tuesday February 26, 2008 @08:00PM (#22566522) Homepage
    Uh.. Turkey Point has *2* reactors and 3 major fossil fuel generators (As well as several generators under 5 MWs).

    • by Anonymous Coward on Tuesday February 26, 2008 @08:05PM (#22566604)
      I demand a recount!
    • In fact, I don't believe any US nuclear power plant has more than three reactors on one site.
    • Re:5 reactors? (Score:5, Insightful)

      by johnny maxwell ( 1050822 ) on Tuesday February 26, 2008 @08:13PM (#22566698)
      Well, the problem is that huge, bulky plants are much more fragile - in terms of network disruptions - than a more distributed net of many smaller plants.

      Nuclear plants however are only available in the huge, bulky variation. In fact they come from some technological stone-age where the idea of giant-gigawatt-city-plants was considered the best solution imaginable.

      Nowadays one tries to break power generation up into much smaller parts - perhaps as far as to your own cellar. This would have in fact many advantages besides reliability, "combined heat and power" comes to mind.
      • Re:5 reactors? (Score:5, Insightful)

        by ColdWetDog ( 752185 ) on Tuesday February 26, 2008 @08:22PM (#22566798) Homepage

        Nuclear plants however are only available in the huge, bulky variation

        Of course, one can have various definitions of "huge" (insert Viagra jokes here), but the US Navy might not agree with you.

        But I really don't think it's a good idea for everyone to have a nuclear reactor in their cellar. Most folks don't have the technologic where-with-all to keep their PC's or cars running correctly. Until and unless you can get any power generation technology simple enough that it rivals a toaster in complexity, I will take centralized facilities any day.

        "Mommy! Why is the basement glowing?.

      • Re:5 reactors? (Score:5, Insightful)

        by Gertlex ( 722812 ) on Tuesday February 26, 2008 @08:49PM (#22567032)
        One does *not* currently try to break up generation into smaller parts for nuclear reactors...

        For nuclear, the economics of initial construction and design requirements make much more sense to do huge reactors. A reactor has to have huge amounts of shielding for protection in case of mishap (it's mostly not for the regular reaction from the core). We're talking shells of concrete several feet thick. And steel too. It's cheaper the larger your volume/power ratio and such is.

        None of the reactors listed here [] are below 1 MW of electric power.
      • Re:5 reactors? (Score:4, Informative)

        by AlvinTheNerd ( 1174143 ) on Tuesday February 26, 2008 @08:54PM (#22567076)
        They are "huge and bulky" because that is what is efficient. A smaller power plant is less efficient especially for nuclear since its main cost is human resources. Having to have a team of engineers for a small plant cost almost as much as for a large plant. That is why you see a lot of multiple cores at single sites.

        BTW, there are very small reactors that are designed for something like a small town in Alaska and also ones for ships.

        And the reason there are a lot of small plants in the last 20 years or so is that the rate of electricity demand is growing slowly and large plants that won't be fully needed for several years weren't as profitable as something smaller albeit less efficient.

        However, that is changing as many companies want to replace groups of smaller plants with a large ones. That and the 'why have anything else' natural gas power plants of the nineties now operate often at a lost and are run only when needed. And the reactors are only getting bigger, not because people still think in the stone age, but because that is what they are being called for. France wants all the power it can get per reactor, they just sell the excess to Germany who is having issues with a stable power grid. South Africa wants 23 gigawatts, China wants 50 gigawatts, Texas 15, UK 20, etc. And they are willing to pay for it, because over its lifespan there are very very few plants that aren't profitable at any scale and many much more profitable than originally thought, look at entrgy and exelon profits in the last few quarters.

        And a large system of many small plants are have great reliability in terms of having some power, but are very poor at consistent power. Germany and Denmark are good examples of nations with many small plants and they depend heavily on other nations power systems as a back up.
      • Re: (Score:3, Interesting)

        by dfenstrate ( 202098 )
        In fact they come from some technological stone-age where the idea of giant-gigawatt-city-plants was considered the best solution imaginable.

        Or the technological stone age where scaling up the volume you use to generate electricity cuts down on the ratio of volume to surface area, where you lose heat and efficiency.

        Good thing we've gotten around that old Length^3 = volume = power production and Length^2 = area = ambient losses stone age philosophy.

        Sarcasm about thermal efficiency aside, the added expense th
      • Re: (Score:3, Insightful)

        by dbIII ( 701233 )

        In fact they come from some technological stone-age where the idea of giant-gigawatt-city-plants was considered the best solution imaginable.

        Thermodynamics is like that, stone age or not. Thermal power scales up giving you more than double the power for twice the size.

  • by AJWM ( 19027 ) on Tuesday February 26, 2008 @08:03PM (#22566564) Homepage
    The power outage -- ie, some serious switch failures -- triggered the reactor shutdown. Nuclear reactors are great at supplying base load power but if all of a sudden the grid goes offline, they have nowhere to send that power and have to shut themselves down. (Power reactors don't do well with highly dynamic loads.)

    It was not, as some posters seem to have misread even the summary, that the reactors went down first and caused the outage. Mind, once the reactors are down it takes longer to bring the whole grid back up, so in that sense it's contributory.
    • by Tesen ( 858022 ) on Tuesday February 26, 2008 @08:25PM (#22566818)
      Actually, I believe they shutdown due to a safety issue. When they lose grid power for powering water cooling pumps etc, their standard response is to shutdown for safety reasons. Yes I know, a power generating plant that gets power off the grid, but consider if the plant is unable to drive a turbine to power its own pumps, where does it get the power from? Okay backup generators, but they can also fail. From what I hear the current dropped enough from the grid to cause them to need to shutdown the reactors. This is a good safety thing. The bad thing is the issues on the grid that caused this and other sites to shutdown generation.

      And now, we return you to regular scheduled blackout... if this were an actual emergency, you would of killed the person sitting next to you.

      • by nbritton ( 823086 ) on Tuesday February 26, 2008 @09:13PM (#22567262)
        The backup generators have backups. All critical systems have at least double redundancy, that's why nuke plants are so darn expensive to build.
        • Re: (Score:3, Informative)

          by pereric ( 528017 )

          Yes, and still they fail. We had a somwhat interesting event at one of our sites in Sweden, Forsmark []: When a fault in the outbound net triggered a shutdown in a similiar way, a power spike at the internal system forced all of the backup generators down, stopping power to the pumps. Fortunately, they were able to be restarted manually.

          There is some debate about whether we had a risk of meltdown (our reactors *do* have some shielding if that would happend), but still the lack of safety culture was heavily

    • by chris mazuc ( 8017 ) on Tuesday February 26, 2008 @08:29PM (#22566862)
      What I've heard on the radio so far (in Tallahassee, FL) is that the nuclear reactors have their coolant pumps connected to the grid so if the reactor ever had to be shut down the coolant would continue to flow, avoiding a meltdown. There was apparently a problem with the substation supplying (backup) power to the coolant pumps, and as a precaution the entire reactor shut down automatically.
    • by jd ( 1658 )
      This would put it in the same category as the massive northeast US seaboard blackout and the London blackout of a few years back then. I'm impressed it only cascaded over such a small region - these sorts of failures (and subsequent surges elsewhere on the grid) have a tendancy to ripple across vast areas very quickly. In the northeast US case, it took out several US States and a large chunk of Canada. This incident merely took out five generators and one small part of one State, which - relatively speaking
  • by Channard ( 693317 ) on Tuesday February 26, 2008 @08:03PM (#22566568) Journal
    ... at least given how much crime shows draw on real life events, albeit massively embellished. Cue Horatio Caine.. 'Looks like someone's been left in the dark.. permanently.' *removes sunglasses*
  • by vanyel ( 28049 ) * on Tuesday February 26, 2008 @08:04PM (#22566602) Journal
    The article says that a switch caused the power outage; if the transmission lines get shut off (perhaps the switch caused a cascading failure, as has happened before), of course power plants (no matter what type) will shut down --- there's nowhere for the power to go!
    • by caluml ( 551744 )

      if the transmission lines get shut off (perhaps the switch caused a cascading failure, as has happened before), of course power plants (no matter what type) will shut down --- there's nowhere for the power to go!
      What they need is a really big lightbulb that they light up if there's nowhere else for the power to go.
    • by HiddenCamper ( 811539 ) on Tuesday February 26, 2008 @08:16PM (#22566730)
      I agree, using the word nuclear in this article was not necessary. The only 'story' about the nuclear plant is the safety system activated, disconnected them from the grid, and scrammed the reactor (shut it down), which just results in less electricity to go around when the grid reconnected. Nuclear reactors take a while to start up, and some models get poisoned quickly if they are shut down and can't be restarted for several days.
      • Re: (Score:3, Informative)

        by bill76 ( 1246926 )
        U.S. power reactors generally do not have any problems starting up after a shutdown due to a buildup of poisons (neutron absorbers) in the reactor. Yes, xenon-135, a strong absorber, increases after shutdown, peaking about 10-15 hours after the scram. It decays to zero in about 72 hours. No, the xenon transient is not the reason why the plant owners don't start the reactors back up immediately. They evaluate the cause of the shutdown and the response of plant systems and make any necessary repairs befor
  • Its a good thing (Score:4, Insightful)

    by Dr. Eggman ( 932300 ) on Tuesday February 26, 2008 @08:06PM (#22566614)
    The system detected there was a problem and automatically shut the reactors down; The system worked! Maybe massive blackouts aren't the best result, but they are by far better than the worst result.
  • by Vellmont ( 569020 ) on Tuesday February 26, 2008 @08:08PM (#22566640) Homepage

    just what technical problems could shut down five reactors?

    If the article submitter had actually read the article, he might have noted the nuclear plants shut down because of an under voltage in the rest of the system (caused by a breakdown elsewhere). My guess is this is some kind of safety measure, otherwise why would you have the system shut down?
  • by dwater ( 72834 ) on Tuesday February 26, 2008 @08:08PM (#22566642)

    Time for this Asia (China) resident to get his own back by tagging this story as 'andnothingofvaluewaslost'. :p

    For those of you who don't know, a lot of the stories about Asian countries losing connectivity to large parts of the rest of the world were tagged as 'andnothingofvaluewas lost'. Of course, it could be argued that it is the countries that lost the connectivity that didn't lose anything of value, but hey.

    I wonder why it is often stated that such places have lost their 'connection to the internet' when at least some of them probably don't much notice (China wouldn't notice much more than MSN not working, for example) - do people think that 'the internet' lives in the USA or something?
    • Not to be an elitist American, but... [] I couldn't find a substantive content map (well there's xkcd's []) but I figure Fiber is illustrative enough.

      At any rate, I also think the tagging system is garbage. I think the best fix would be to let the submitters specify the article tags. Yes, give me the POWER! I mean us! Us the article submitters!
  • This is kind of a blow to the pro-nuclear power constituency, but outages are always a possibility. Safety nets and first response triggers are essential and this problem was corrected rather quickly so I still have confidence in the system.

    On a side note:
    I really hate how every problem requires a clarification that it wasn't Terrorists.
    We live in a state of fear, and not a state of freedom. Are there people that really freak out and cry "Terrorists!" when something goes wrong these days. I'm not complacent
    • by Dun Malg ( 230075 ) on Tuesday February 26, 2008 @08:28PM (#22566854) Homepage

      This is kind of a blow to the pro-nuclear power constituency
      Except that it isn't. If you, the submitter, or the Slashdot "editors" had RTFA, you'd have realized that the reactors shut down because of the blackout, not the other way around. The blackout was caused by switching equipment. The circuit being broken, the reactors had no place to dump their power output, so they automatically shut off. That's what is supposed to happen. Nothing nuclear to see here, move along.
  • FPL just wanted to make sure everyone tested their backup generators prior to hurricane season.
  • by Bryansix ( 761547 ) on Tuesday February 26, 2008 @08:13PM (#22566700) Homepage
    Did anybody seem to notice that while yes, the nuclear plants shut down, so did the coal plants. Neither of of the plants had problems. It was a problem with the substation.
  • by gardyloo ( 512791 ) on Tuesday February 26, 2008 @08:16PM (#22566734)
    (NPR is running a story on it right now):

        These plants were designed to shut down in case of a fall in the power reaching them from *other sources* (because they need, e.g., to run cooling pumps for a safe shutdown and can't count on their own power). I'm not sure why the outside power browned out, but it did, so these plants did what they were designed to do.
  • by jd ( 1658 ) <> on Tuesday February 26, 2008 @08:19PM (#22566758) Homepage Journal
    Nuclear reactors are, by design, extremely sensitive to unexpected conditions. The reactor fire at Windscale, amongst others, convinced reactor designers very early on to install mechanisms for shutting down reactors quickly and safely. Graphite rods, held by fail-safe hair-trigger mechanisms, can be slammed into place, shutting down a reactor quickly. Failures in the lowering of the control rods have happened, but are fortunately rare.

    What would it take to trigger the automatic release of the control rods? An earth tremor above a pre-set limit, insufficient input of cooling water from rivers (or water that's too hot or too impure), a controller hitting the wrong switch, a software glitch, a glitch in a clock crystal screwing with timing calculations, a loose connector, a chip in an old-style spring-based socket catapulting itself into the air (which they had a nasty habit of doing), erronious control signals from other power stations, a downed power line on any segment with single points of failure, etc.

    Of these, the vast majority apply to any power station - one line down not too long ago caused a blackout that covered three States and half of Canada. One line down between the east and west coasts about 14-15 years ago shut down large parts of the northwest USA for a couple of weeks. Cascading failures are inherent in the meta-stable mashup of networks that form the power grid. Too many SPFs, too little redundancy, too many communication glitches, too few contingency plans.

    Personally, I think the grid needs to be massively redesigned, with far better (and more intelligent) signalling, far more redundancy at all levels and a huge upgrade on software and hardware (NT4 and Windows 3.11 are not acceptable to me for mission-critical systems - they're tried and tested, but they're not reliable and they're not secure).

    Of course, this won't happen, massive cascading faults will continue to be reported on a regular basis, and people will continue to be surprised when they occur. Preventative maintenance on the scale needed to cure the system as a system is so expensive (even though it's one-off), the distributed costs of regular blackouts on even a gigantic scale look cheaper on the balace sheet, so an inefficient, decrepid, flawed power grid becomes the preferred option.

    • Re: (Score:3, Informative)

      'Control rods' are not graphite; they are made from something which is a neutron absorber. This is most usually a boron or cadmium containing material. Graphite is used as a neutron moderator. I'd be surprised if the shutdown in this case was automated. Automated shutdowns are rare; the operators normally have plenty of time to shut down before the things become potentially dangerous and a automated shutdown is triggered.
  • by evolvearth ( 1187169 ) on Tuesday February 26, 2008 @08:21PM (#22566784)
    I was on campus completely oblivious that anything happened. My girlfriend called me six times in a row, and while I had the phone on vibrate as to not to disturb the interesting lecture on the horribly long lab I'm going to have next week, I was irritated and concerned. I called her after class to see what's up, and that's when I found out there was an outage. The science and engineering side have nice generators, hence my ignorance. The building my girlfriend, Cooper Hall, is a death trap. Apparently, the idiots at USF made sure that when the electricity is out, people are actually locked inside the building. All of the doors were locked from the inside. What the hell would happen if there's a fire? I understand that's the inferior side of campus, but there are people in my phonebook over there and therefore I'm concerned!
  • It's sad, but thanks to FPL and our largely-complicit state legislature, Florida has the power grid of a minor rural village in a POOR third-world country. Name ANY other place in the developed world with the size, population, and average wealth of Florida where it would EVER be considered acceptable to have more than a hundred thousand customers without power for more than TWO WEEKS after a hurricane that barely left a dent in anything besides the power grid itself (Hurricane Wilma... 15 days, 17 hours wit
  • The account I read stressed that two nuclear reactors had shut down in a way that implied they were the cause. They interviewed a plant supervisor who said things had shut down as they were supposed to and everything was OK, as they are supposed to say.

    Right at the end the article also mentions that two coal-burning plants shut down as well.

    Same thing, so why the emphasis on the nuclear plants?
  • by A nonymous Coward ( 7548 ) * on Tuesday February 26, 2008 @08:27PM (#22566848)
    I smell something fivey .... the Pentagon!
  • ..broke the cable, same as the other five 'net cables.

    Happens all the time....

    There is a fleet of ships...ah.. trucks repairing these things round the clock.

  • by iabervon ( 1971 ) on Tuesday February 26, 2008 @08:50PM (#22567040) Homepage Journal
    The electrical grid is a really tricky system. You've got generators putting in energy at a bunch of points. And the whole thing is AC, which means that, if you look at any particular point, you see the voltage (and current) going in a sine wave. If you drive the system at the correct phase, you're supplying power; if you're slow by 1/120 second, you're turning twice your capacity into waste heat, and you start blowing up substations. Furthermore, since electricity moves at a finite speed along the wires, you can't just have a really good clock and have everybody agree; the difference in phase you need depends on the distance between the power plants along the wires. The solution is to have the power plant measure the phase of the lines they're on, and generate with a matching phase.

    Now, if something goes wrong somewhere down the lines, the power plant may not be able to get a good read of the phase. At that point, you just shut down the power plant, shut down the substations (so there isn't customer load on the lines), get the switching stations fixed, start the power plant up again in phase, and reconnect the customers. It's only if the switching stations are really destroyed that they'd actually run a power plant for local customers disconnected from the national grid, and they'd have to shut it down again in order to rejoin the grid.

    What happened today is actually how it's supposed to work in case of an equipment failure: a regional blackout, some time to repair the malfunctioning equipment or swap in replacements, and then restoring power. When the grid doesn't handle the failure correctly, power lines melt down and power company manholes and buildings blow up and service isn't restored for days to some customers.
    • by Technician ( 215283 ) on Wednesday February 27, 2008 @01:16AM (#22569504)
      The solution is to have the power plant measure the phase of the lines they're on, and generate with a matching phase.

      ROLFLAMO Power into and out of the electrical grid is not by the phase of the generator. Power into and out of the grid is by the prime mover, eg throttle and nothing else. Once a plant is online, the throttle doesn't change the phase, just the power. (infinate grid calcultions) Matching phase while connected is not monitored as the electrical locks it to the grid. Power factor is controlled by the voltage regulator. Over voltage produces a leading power factor and under excited generators produce a lagging power pactor. Excitation is used for correcting power factor with some voltage regulation/correction.

      Matching phase is only something you do just before closing the breaker and it is almost always closed slightly out of phase by about 5-10 degrees leading while advancing (running slightly fast) so it can connect with little bounce. After that, it's in phase, even if the prime mover is shut down. (reverse power protection should relay it out at this point to allow it to stop rotating)

      Disclaimer, I am not a powerhouse operator, but I am the son of a retired one.
  • by achurch ( 201270 ) on Tuesday February 26, 2008 @08:51PM (#22567050) Homepage

    1998: "A massive power outage left millions of people without power Friday. The cause of the blackout is unclear."

    2008: "A massive power outage left millions of people without power Friday. The government says terrorism was not involved, but the cause of the blackout is unclear."

    Sigh . . .

  • by John117 ( 717182 ) on Tuesday February 26, 2008 @09:30PM (#22567384)
    Most everything's been covered here, but I'll put my two cents in as a Nuclear Engineer (albeit in PA). Nuclear power plants run all safety systems on offsite power. This is a perfectly understandable setup, because if something goes wrong and we need to scram the reactor, the safety systems need to keep running. At my plant, we have two completely separate backup diesel generators to supply power in the event of loss of offsite power, but shutdown is nevertheless the automatic response, both because the diesels won't run forever and because a sudden loss of load messes with a very delicate balance of turbine power, reactor power, and load. Nuclear power is a popular black sheep for these kinds of events because people are afraid of it, and the news media profits from sensationalist broadcasting. Whatever garners the greatest response, they'll run with it. As for the grid as a whole, it is not a Florida problem. The same issue came up with that massive northeast blackout in what was it, 2003? The whole system is ancient, but it's too expensive to completely overhaul it, not to mention people wouldn't stand for the loss of power as systems were replaced and/or updated. In terms of power distribution, there's a delicate balance as plants come on and offline and demand goes up and down. Any significant transients (like this undervoltage line) just causes a complete mess. This is a problem that's only going to get worse as power demands continue to rise, especially if we don't build enough plants to keep a healthy amount of excess capacity.
  • by PPH ( 736903 ) on Wednesday February 27, 2008 @01:39AM (#22569724)

    According to various reports, the outage began with equipment failure and the loss of a distribution substation. Unlike major transmission links, distribution substations feed local loads and are not a part of the transmission system critical to the movement of power between alternate sources. The loss of a distribution system results only in the loss of loads, not generating or transmission capacity.

    Two things may have happened here. Neither bode well for the system's condition.

    It is possible that, following a fault at the distribution substation, the primary protection relays failed to operate. There are (or should be) backup relays. But these typically take longer to operate and allow the fault transient to push the system into an unstable condition. This is bad design. System stability should be maintained even if one station's protection fails.

    It is also possible that, in spite of the proper design of primary and backup protection, the regional grid is being run too to its stability limits. A fault condition properly considered in the system design which should not have caused stability problems did so because the system was being run beyond prescribed limits.

    Both of these possibilities suggest that, in spite of the big midwest outage we had several years ago, lessons have not been learned.

"The number of Unix installations has grown to 10, with more expected." -- The Unix Programmer's Manual, 2nd Edition, June, 1972