NRC: 9 Nukes Knocked Off Line by Blackout

Reuters | August 14, 2003

[taxcontrol]

I suspect that these plants were all scrammed (rapidly shutdown). The biggest constraint on re-starting, I would guess, is going to be whether the grid is restored and stable for the individual plant and how long it will take to work through the necessary paperwork

---

When the grid fails like this, the effect on the Nuke plant is that all of a sudden they go from 99% load to 0%. Has a h**l of an effect on generators so you have to shut them down pronto to avoid damage. This means no more power from the turbines. But to stop the turbines, you have to redirect the flow of steam, thus the large blow off of steam.

Without the transfer of heat to the steam system, the reactor will rapidly overheat. To prevent this, the uranium is allowed to return to their graphite housing which breaks the nuclear reaction - scramed. This whole process can be completed in a few min.

The problem is bring stuff back on line. It is my understanding that after a scram, the inspection / certification / paperwork to reactivate can take WEEKS.

We could have a major problem restoring power.

[Delta 21]

Pi are round, Cake are square.

[TheFrog]

"Without the transfer of heat to the steam system, the reactor will rapidly overheat. To prevent this, the uranium is allowed to return to their graphite housing which breaks the nuclear reaction - scramed. This whole process can be completed in a few min." ß Lets try more in the order of 7.8 to 8.2 seconds. Been there done that.

"The problem is bring stuff back on line. It is my understanding that after a scram, the inspection / certification / paperwork to reactivate can take WEEKS." ß But usually back at power the next shift.

[TheFrog]

Re: "the uranium is allowed to return to their graphite housing" Not at a Pressurized or Boiling Water Reactor. No graphite moderated commercial reactors still operating in the US.

[70times7]

This may have been addressed elsewhere, but I'll post it anyway. There is a big difference between the reactor being down and the facility being down, as in not supplying power to the grid. I'm no expert, but I can't imagine those facilities would be built without a way to dissipate the heat without running the turbines.

[70times7]

Why the heck am I doing this?! I'm in California!

It cracks me up when people answer their question within the question itself!

[70times7]

Hey Delta - have you ever seen this show in Boston? it is awesome! We sat just outside the cables at the lower right corner of your picture.

[Delta 21]

Never seen that one. El Paso has a fairly large coil setup that arcs a lightning bolt about 25 feet.

I built one when I was in high school that lit up about 30 flourescent bulbs in the ceiling of the cafeteria when I turned it on. Scared the hell out of the whole school! It was way cool.

[TheFrog]

Re: "I can't imagine those facilities would be built without a way to dissipate the heat without running the turbines." <-- They do!

[70times7]

Let me try again: I am sure those facilities have a way to dissipate the heat with the turbines down without taking down the reactor itself.

(all my poor phrasing are belong to us)

[70times7]

You have brought back memories of my dorky, yet amusing, middle school science teacher. One day he brought in a 3 to 4 foot tall VdG generator. Among other demonstrations, he stood on a black rubber mat and zapped himself for the class. He wondered aloud why he was not well enough insulated to lessen the shock to his hand. I learned later that in some black rubber mats the coloring agent privides conductivity.

ZZZZZZZZZZZAP!!

[snopercod]

I can't imagine those facilities would be built without a way to dissipate the heat without running the turbines.

They dump the steam (which normally goes to the turbines) to the atmosphere through a number (16?) of very large valves (8" IIRC). The steam blows hundreds of feet into the air, and is very loud.

During the startup of Diablo Canyon out in California, the first time they tested that, the noise blew sheet-metal panels off the side of the turbine building.

[snopercod]

If you know anything about nuclear power plant operation, then you are aware that the loss of all offsite power is not just a routine upset - it can turn into a major crisis.

[bagman]

Certainly when the grid goes away, a power plant has to shed a lot of energy (and steam in the case of a nuke or a coal-fired plant) in a hurry. The reactor pressure will initially go up but it will very quickly go down due to the rapid cooldown of the reactor coolant system. The reactor pressure control system is designed to handle all of these effects.

I'm not sure what this graphite housing is. When the reactor is tripped (shutdown), the control rods, which absorb neutrons and shutdown the chain reaction, are rapidly inserted into the core. Control rods are typically made of silver, indium, and cadmium, although some reactors use boron carbide rods (the boron is the neutron absorber in this control rod).

It does not take weeks to start back up a reactor. If you know why the reactor was tripped (in this case we do) and all the equipment is functioning, then the reactor can be very quickly re-started. I suspect that the shutdown reactors will be res-starting any time now (it's about 8:30 am, Friday as I write this).

[Rightwing Conspiratr1]

I have a VERY HARD TIME believing there's ONLY a simple, natural, no-skull-duggery explanation for this.
I just don't believe it.

No really it was just a common ground squirrel caught in the transformer on the power grid. There is no evidence that it was wearing a turban and had trained in Iran. ;-P

[taxcontrol]

I did not know that - thanks for the info.

[Quix]

There were relatively specific prophecies about such. I may get one posted later.

I don't know that it was a specific terrorist act--though certainly computer hackers of Al Qaeda etc. vintage have been trying for such rather relentlessly.

But even just the negligence that currently appears involved is suspicious to me.

And all this like just heard on Fox: "We have not been able to pinpoint the cause of this massive outage."

. . . . that's just . . . . so at best weak to me. There's just toooooo much slipperiness still.

Maybe there was no overt active conspiracy type action involved. But there sure was some set-up involved, then--if only of a deliberately negligent sort. There were too many outages of massive proportions in decades past for there to have been no solution at this point. Our technology is not REALLY in the dark ages like this makes it look like.