My father (now deceased, wish he was here to consult), when working, designed the largest power generators for GE. He told me that if the whole North American grid went down, it could not be brought back. There reason is that it takes electricity to generate large amounts of electricity. Electricity is generated by moving a coil of wires in a magnetic field, the rotor coil can be moved by water, steam, wind, etc. For large systems, the magnetic field must itself be generated by electrical currents in stator coils around iron cores -- so called "permanent magnets" won't suffice. When one part of a grid goes down, electricity from adjacent grids is needed FIRST to activate the stator magnets. When there is no electricity to activate the stator magnets, moving the coils will not generate any electricity. I don't know what coordinated efforts of using smaller generators (that use batteries for activating the magnetics) would be needed to bring just one major station up. Some major contingency planning would be needed to organize the smaller generators.

Is this still a problem? Thanks. Larry

-- Anonymous, March 08, 1998

Answers

Laurence,

My cousin works for a power company on the high plains. I asked her how they would bring up their grid in the event it went down, she said there was one gas fired generator in a small New Mexico town that was started first, that was used for the next, etc.

J

-- Anonymous, March 08, 1998

Good question. All power plants need a source of electricity to start themselves up. Not only for the stator, but for lots of other things, (including those troublesome computers). Many power plants depend on getting power from the grid, which of course won't work when the grid is down. Having a local source of independent power, often a diesel generator, is called "black start capability". All the nuclear plants are required to have black start capability. To make a wild guess about non-nuclear plants, I would say 1/3 of them can black start.

Is that enough? To my knowledge, nobody ever calculated how much faster we could restart after a blackout if more plants had black start. My guess is, not terribly faster, because there's lots of other hurdled to overcome also besides just black start capability.

BTW, human intervention can be ingeious. After the BIG blackout, Novermber 9,1965, one of the plants in NYC which didn't have black start capability, did manage to black start using office furniture to start the fire in the boiler. It sounds ridiculous, but it *did* work.

-- Anonymous, April 10, 1998

Nuclear plants have a larger paracitic load, if I am remembering right, than coal-fired plants. Al American nuclear plants have large diesel generator plants with 8 to 16 engines large enough to power a good sized ship. These engines can be brought on line just as you would start a fleet of taxicab engines, but they can also be synchronized so that all of their opwer is useable. That does not mean that this provision is necessarily adequate.

For instance, at an oil-fired plant that went down at an industrial facility, the emergency diesel generator could not be started because operators forgot to shed all of its load. They burned up several air-start motors trying to get it cranked. Power was off line for about 12 hours, and significant econimic cost waw suffered. Will operator errors such as these creep into things in January 2000? I think so.

Further more, this plant had orginally used a Terry Turbine to run the feedwater pumps. But some genius decided the turbine was unreliable or troublesome--tsmall steam turbines really are aggravating--and replaced it with an electric motor. Of course, the steam boiler and steam turbine could not "black start" becasue there was not enough juice for this relatively small electric motor that kept the boiler supplierd with water.

Wehn a nuclear plant is first started, it tamakes a severe demand on th whole grid, and about 0.25% or more of the plant's output is required as input from somewhere to start circulating the pumkps and heading the thing by friction of water coursing through the pipes. I am not under the impression that susequent re-starts take that much power, but lots of motors inhabit a nuc plant.

A worse problem is that steam plants require a carefully-planned, and very orderly shut-down. Nuclear plants are much more durable in this regard. Kingston (in eastern Tennessee) had a bad shutdown in about 1986, and it wrecked one of the boilers. This put the unit off line for upwards of a year. If coal plants flop off line because operators are inattentive, or because management is too cowardly to start cooling them off when it seems clear that no more coal is coming--or not enough coal to run all of the units--then we could have great heaps of costly ironmongery dotting America's countryside in March of 2000.

-- Anonymous, April 13, 1998

Good discussion so far. There are two types of power plants: those capable of black start and those not capable of black start. What has been left out of the discussion is that some diesel generator control systems used to provide black start capability have the same embedded chip y2k problems that will cause the problem. How do I know this, because I have a letter from a major diesel generator manufacturer telling me that some of its contol systems for its older diesel generators are not y2k compliant.

Well, if the grid goes down in an area (I don't think the whole country would go black), it could take a while to get things back up. One of the reasons is that most black start capable plants (although a some of hydro doesn't) require diesel generators to get the contols systems, computers, and intial systems up and operating operating.

There are quite a few black start capable plants and the emergency generator manufactures are taking this real serious as they have a lot of potential liability. I think if the utilities prioritize the systems they work on in generation, transmission and distribution, that the effects of y2k will only be isolated locations.

Bob Schneider V.P. D. Hittle & Associates, Inc.

-- Anonymous, July 11, 1998

At one black start capable plant belonging to CP&L, (Hyco Plant) a plan dating back to the seventies is in place. As follows: 1. Use plant switching locomotive to jump start gas turbine generator. 2. Start unit 1 (approx 325MW) using gas turbine power. 3. Start unit 2 (approx 380MW) using unit 1 or gas turbine. 4. Start unit 3 (approx 650MW) using unit 1 or 2. 5. Start unit 4 (approx 650MW) using unit 1, 2, or 3. 6. Using inter-plant tie line, start the nearby Mayo plant (approx 650MW). As far as I know this was used once, in the early eighties when a transformer explosion at the Hyco Plant knocked both plants off-line. My source tells me that some improvements were made at Hyco for the units being able to better support each other when the plant is disconnected from the rest of the system.

-- Anonymous, August 19, 1998