Richard Ducote: Palo Verde Nuclear Plant a Success in Brief Failure
Jun 19 - Arizona Daily Star
The lights went out for about 65,000 Arizonans early Monday.
A disturbance on the transmission system in, fittingly, Surprise, was blamed
for temporarily cutting service to scattered customers in Tucson, Phoenix and
even as far away as California and New Mexico.
For about one hour, TV sets went dark, toasters went cold and computers
blipped off for a small fraction of the customers plugged into our state's
electric grid.
The news is good because the potential was there for a huge power failure
across the whole Southwest that could have damaged the economy and even
threatened lives.
Just as daytime temperatures were beginning to cook on a typically hot June
morning, an insulator failed on a transmission tower, causing a power line to
fall and short-circuit.
In an instant, the huge Palo Verde Nuclear Generating Station 50 miles west
of Phoenix went off-line and shut down.
Tucson Electric Power is not among the seven utilities that own shares of
Palo Verde, the largest nuclear power complex in the nation.
But Tucson customers were using about 60 megawatts of power when the failure
hit.
All utilities are tied into the network and power is bought, sold and shared
all the time as the market changes minute to minute.
When Palo Verde is cranking at full power, it puts out nearly twice as much
electricity - 3,800 megawatts - as all TEP power plants combined. Palo Verde
alone can supply 3 million homes.
A power source of that size benefits the whole state. It is but one plant
among many that are feeding the grid. But it is the 800- pound gorilla of
plants. Losing it all at once is like losing two cylinders in your 350 V8 while
roaring up I-10.
The unprecedented loss of all three Palo Verde units in the blink of an eye
is remarkable for what did not happen next.
The grid sagged momentarily, adjusted for the loss, and shed just a few
thousand customers for a brief time, thus saving the larger system a much bigger
failure.
Our region happens to be flush with electric generation capacity just now.
Several thousand megawatts of new plant capacity have come on line in recent
years, partly because of the false start of power deregulation, a craze that
swept the halls of regulatory agencies in the last decade.
Because electricity is essential to maintain life, health and commerce, we
rightly build redundancy into generation and transmission assets while trying to
maintain some economy for ratepayers.
Restarting Palo Verde will take several days. Other plants in the region will
pick up the slack.
We need to be mindful of the need for reliable service when expansions of
generation and transmission facilities are needed.
The success of the Palo Verde shutdown shows we have done things right in the
past.
We cannot squabble about every transmission pole and power line that needs to
go up without dire consequences when some future glitch challenges the system.
Utilities, regulators and the public need to ensure that we continue to do
things right for the future.
Contact Richard Ducote at 573-4178 or ducote@azstarnet.com
.