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Peak electricity down for California By CARRIE PEYTON Scripps-McClatchy Western Service October 06, 2000
SACRAMENTO, Calif. - For the first time in years, California's peak electricity use has dropped.
That's right. Dropped.
After a summer of emergency alerts, near blackouts and pleas for conservation, California ended the air-conditioning season without ever passing the record set last year for the most megawatts zipping over electric lines.
In Sacramento, it was the first time since 1994 that SMUD hasn't racked up a record "peak" - that moment on a hot afternoon when air conditioners are going full blast and more power moves through the system than any other instant of the year.
Peaks force power plants, transmission lines and substations to work their hardest. If anything, it is peak usage, coupled with dwindling power imports, that is likeliest to push California over the brink to forced blackouts next summer.
No one knows for sure how the region and state managed to lower peak use when electricity consumption is on track to set new records this year.
But whatever deflated the summer's peaks could come in even handier next year when a steep shortfall in electric supply is forecast.
Some popular theories for the energy thriftiness? Higher prices. Forced cutbacks. Cool spells. Conscience.
"We think that our customers really came through for us," responding to pleas to use less power during critical afternoon hours, said Doug Calvert, Sacramento Municipal Utility District manager of power system operations and reliability.
Calvert believes that Sacramentans sat up and noticed when the Bay Area was struck with rolling blackouts on June 14, even though that problem wasn't directly related to looming statewide power shortages.
"It's right next door," he said. "Seeing it happen, where you had actual rotating blackouts in San Francisco, it made the problem a lot more realistic to people."
In San Diego, the problem got as realistic as anyone could stand when wholesale power prices were passed directly to consumers, raising average household electric bills from about $50 to $120 and straining operating budgets of schools and businesses.
People responded by cutting use so sharply that San Diego Gas and Electric Co.'s peak wasn't just lower than last year's - it was the lowest since 1997, despite a steady 1.5 percent increase in electric hookups each year.
This summer, San Diego's overall electric usage dropped about 5 percent.
"The rate increase certainly has had an effect," said Art Larson, an SDG&E spokesman. He estimates that rate-related conservation averaged about 200 megawatts on any given day - enough to supply 200,000 homes.
Lower usage in San Diego helped suppress peaks statewide, according to the California Independent System Operator, which runs the electric transmission system that supplies about three-fourths of the state.
An even more significant dent - sometimes up to 1,800 megawatts - came from "interruptible" customers, those who get lower electric rates in exchange for being ordered off the grid when supply is tight.
But here's the unusual thing: Even after adding all the interruptible power back in to the busiest day last summer, California used less electricity at its summer peak than on the busiest day the summer before.
In 1999, utilities fed through the ISO-controlled grid - including San Diego, Southern California Edison and Pacific Gas and Electric Co. - peaked at 45,884 megawatts.
In 2000, the same users peaked at 43,784 megawatts the afternoon of Aug. 16, and went no higher because 1,710 megawatts in "interruptible" load was ordered off the grid. That created an "adjusted" peak of 45,494 - still below the record last year.
The statistical oddity raises a question - how did a state that never surpassed 1999 records still end up so energy poor that more than 30 "Stage One" electric emergencies were declared? The answer, according to Jim Detmers, the ISO's manager of operations, is that even though peak usage dropped, vital out-of-state supplies dropped even faster.
California has long relied on power plants in the Northwest and Southwest to sell electricity here each summer. That system has worked for years because the Northwest tends to peak in the winter, and the Southwest got ahead of expected growth and built more power plants than it needed right away. Growth in both regions has changed that picture.
This summer, when California needed up to 8,000 megawatts of imported electricity for its forecasted peaks, available supplies often dropped to 4,000 to 5,000 megawatts, Detmers said.
The public spotlight that accompanied that sense of crisis also helped whittle away at peak usage.
The weather helped, too, said Detmers. Even though there were hot spells, the ISO "weighted average" of hottest days across the state was about 4 degrees cooler this year than last.
"It was a nice, nice summer. I'll ask for another one of those," he said.
-- Martin Thompson (firstname.lastname@example.org), October 06, 2000