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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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  • 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!
  • by xaxa ( 988988 ) on Tuesday February 26, 2008 @08:22PM (#22566800)
    You joke, but a few years ago my physics teacher showed me a video of a really dense part of a power grid (right next to the power station) when something failed and the power had nowhere to go -- the wires drooped, then glowed red/orange/white hot as they melted and snapped.
  • Re:5 reactors? (Score:2, Interesting)

    by johnny maxwell ( 1050822 ) on Tuesday February 26, 2008 @08:35PM (#22566918)

    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.
    Yes, it's mostly because of security concerns! But that's just the point, you can build small nuclear reactors - but build securely (that is with multiple layers of containment, emergency automation, a couple of engineers, etc. pp.) they just aren't profitable. That is, if you not happen to be the military - they have quite different views on cost-benefit :)
  • by jd ( 1658 ) <imipak@@@yahoo...com> on Tuesday February 26, 2008 @08:42PM (#22566972) Homepage Journal
    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 - is damn impressive in terms of automatic and human responses.

    I would want to know more about the maintenance on those switches, their rated capacity, and why enough could fail at the same time to reduce transportable capacity. Even with infinite switches, there'd be a non-zero probability of a complete across-the-board failure, but provided everything is well-maintained, you only need to guarantee that at any given point in the system, what you have spare exceeds what is likely to simultaneously fail, for an acceptable level of "likely".

    Were there unnecessary single points of failure or inadequate backup mechanisms? Did so many switches fail at the same time because they were rated far too low for current usage or because poor maintenance degraded them below the ability to handle current usage? Nuclear reactors are extremely bad at handling dynamic loads, so what is going into developing mechanisms for soaking up (or burning up) power when grids do go offline? (Reactors aren't trivial things to restart.)

  • Re:5 reactors? (Score:3, Interesting)

    by johnny maxwell ( 1050822 ) on Tuesday February 26, 2008 @09:15PM (#22567276)

    You really think a tiny little turbine is going to be as efficient as a huge one in a powerplant?
    Yes, I do.
    Of course the great turbine in the power plant is more efficient as my tiny little local one, but the power from the large, centralised and thereby far-off power plant has to come to me first. The biggest consumer on the net is the net itself. Most of the power is just lost traveling to my home!

    But that's not even the worst part: what about all the heat? In a big power plant it is usually just blown in the air (or at most used locally). With village-sized plant most of it could be harnessed.

    Ok, in Florida you probably don't have to heat that much during the year(?) but its rumored that there are unfriendlier places.

    Generally bigger things are more efficient. (Excluding future techs and unobtainium).
    Like a centrally planned economy? Or perhaps like a mainframe? We should ask the dinosaurs!
  • Re:global warming (Score:5, Interesting)

    by Anonymous Coward on Tuesday February 26, 2008 @09:19PM (#22567296)
    The reactor shut down due to the no load condition. And they can't start it up for several hours due to xenon preclusion. If they didn't shut down the reactor it would have shut itself down due to the large xenon transient. This is common knowledge for nuclear engineers. If you lose your load on a nuclear reactor, you must shut down due to the massive xenon transient. If you are not familiar with this then you should read the reactor fundamentals handbook link above. This isn't rocket science.
  • Re:5 reactors? (Score:3, Interesting)

    by dfenstrate ( 202098 ) <dfenstrate@gm[ ].com ['ail' in gap]> on Tuesday February 26, 2008 @09:32PM (#22567394)
    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 that comes with nuclear- the staffing, the regulatory issues, the security, the higher quality requirements, the safety systems- means that only the largest units are economically viable. New Nuclear power plant designs are even larger (A new GE design is on the order of 1,600MWe) for those reasons.

    Now, certain large institutions may be turning toward combined heat and electricity generation. This makes perfect economic sense for those organizations, but it's not a larger trend. I won't go into the economics of it, but you're not going to have a combined heat-power generator in your basement, and neither is the walmart down the street, because the economics aren't there and won't be for the forseeable future.
  • by grapeshot ( 1022375 ) on Tuesday February 26, 2008 @09:35PM (#22567426)

    Exactly. The FIRST time you sync a new generator to the grid, that can get a little hairy, because you've got to get the phases checked to make sure their rotation matches with the phase rotation on the rest of the grid. But once you've got phase match, with modern sync check relays and automatic syncing and switching it's pretty routine.

    Now...back in the day, before modern digital relays, when you had to watch a rotating needle on a dial and the three blinking lights, and the sync check relay was an electromechanical device, yeah, it could get a little hairy to switch a generator onto the grid.

  • Re:global warming (Score:3, Interesting)

    by dgatwood ( 11270 ) on Tuesday February 26, 2008 @09:55PM (#22567650) Homepage Journal

    I am not a nuclear engineer, so maybe I'm missing something obvious. That said, I don't understand why the system would automatically shut down due to a no load condition.

    I understand why a backup generator for a house does this. It's to prevent linemen from getting killed touching lines that they assume are not hot while repairing a downed power line. One would not expect a lineman to assume a nuclear plant's output lines are not hot, however, so that reasoning doesn't apply.

    I might be able to understand them shutting down the power output, if only to avoid problems when they have to resynchronize the phase of the power when the lines go hot again, but I don't see any reason that should necessarily be linked to the operation of the nuclear pile. The nuclear pile is just moving a bunch of steam around. It can do the same thing whether the turbines are under an output load or not.

    At worst, I'd expect the water to move faster through the turbines because there wouldn't be as much resistance to spinning them, and maybe not even that, assuming there are governors on the turbines... unless, of course, the governors are simply insufficient to handle that situation, in which case that screams "design problem" to me.

    I assume that the multi-day outage could have been avoided if the reactor were brought down slowly instead of being scrammed. If so, one would expect that a human being should be required to push the button to shut down a reactor for lack of load reasons, particularly when shutting it down completely requires a multi-day rest period for reaction byproducts to degrade. I would expect that the only time a reactor would be scrammed automatically is when there's a safety risk to its continued operation, and I don't see why a decreased load would qualify as a safety concern.

    Am I missing something fundamental here?

  • by ZJVavrek ( 952066 ) on Tuesday February 26, 2008 @10:15PM (#22567838)
    The premise of continually saying it wasn't the fault of terrorists is to keep the belief that someday it could be terrorists in the mind of the populace.
  • by jfim ( 1167051 ) on Tuesday February 26, 2008 @11:28PM (#22568570)

    Just so you know, three weeks after Ice storm 1998 [wikipedia.org], there were still about 700k people without electricity in the middle of winter(most houses use electric heating and usual temperatures around that time of the year are below zero).

    I presume they want the easement to bury long distance powerlines, not the ones for local distribution. Wikipedia seems to mention that electric power transmission lines [wikipedia.org] are very seldom underground. Of maybe they're concerned about being sued for EMF-related medical issues [wikipedia.org].

  • Re:global warming (Score:1, Interesting)

    by Anonymous Coward on Wednesday February 27, 2008 @12:48AM (#22569300)

    If you lose your load on a nuclear reactor, you must shut down due to the massive xenon transient.
    My sister wants to know if you're up for a date tomorrow.
  • Re:5 reactors? (Score:3, Interesting)

    by Ihlosi ( 895663 ) on Wednesday February 27, 2008 @05:25AM (#22570986)
    So you'd rather have the thermodynamic inefficiency of distributed generation than the bureaucratic inefficiency of centralized generation?

    Don't forget about distribution and conversion losses.

"I'm not afraid of dying, I just don't want to be there when it happens." -- Woody Allen