California Blackout potential remains

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Published Sunday, August 6, 2000, in the San Jose Mercury News

Blackout potential remains

Electrical system: Deregulated industry's shortcomings and overloaded lines put state on brink of collapse in June heat. BY STEVE JOHNSON Mercury News

At precisely 1:13 p.m. June 14, California got an ugly lesson about the precarious state of its electrical system.

As the Bay Area sweltered from record heat, state officials in a command center just east of Sacramento were deeply worried.

Voltage readings at a Newark transmission-line substation had veered into the danger zone. The officials faced a dilemma: either shut off power to thousands of homes and businesses in the Bay Area or risk a catastrophic failure that could spread through the state's 124,000-mile power grid.

The events of June 14, which culminated in the extraordinary step of imposing rolling blackouts on almost 100,000 PG&E customers, illustrate vividly how a combination of factors can bring California's electrical infrastructure to the brink of collapse.

A report presented by two top energy officials to Gov. Gray Davis on Wednesday, along with recent interviews with key government officials, provide the fullest details yet about what happened June 14. Because the conditions leading to blackouts still exist, the report and these sources say, a similar episode could easily happen again. But next time, the event could be more widespread.

As the report put it: ``These serious, but thus far isolated, examples represent a precursor of what lies ahead for California over the next 30 months.''

A system at its limits

This summer, two years after California became the first state in the nation to deregulate its energy market, the plan was in disarray. Despite the enormous influx of new residents in recent years, no new power plants had been completed for a decade. Vital high-voltage lines were regularly strained.

Moreover, suspicions were growing about the operating procedures of the power-supply firms that had ventured into this newly competitive business.

All it took was record heat to push the system past its limits.

Even before the Bay Area woke up June 14, officials at the state's Independent System Operator in Folsom were bracing for trouble. Their job is to monitor the electricity surging across California's vast network of power plants, high-voltage lines and transformers, lining up sources of power and dispersing it.

They didn't like what they saw.

There were forecasts of triple-digit temperatures. That meant a lot of air conditioners would be going full blast, sucking up power. So at 7:30 a.m., the ISO alerted Pacific Gas & Electric Co. to begin seeking voluntary power reductions at noon from large business customers who previously had agreed to switch to backup generators in such emergencies in exchange for lower rates.

That would save about 500 megawatts. During peak summer periods, consumers on the portion of the power grid that the ISO manages in California use as many as 46,250 megawatts of power, with one megawatt sufficient for 1,000 homes. Yet at those peak periods, the state usually has only 46,400 megawatts available. With power consumption this day predicted to be about 45,000 megawatts, that would be cutting it close.

If something unexpected happened, such as a power plant breakdown, the ISO's officials knew, they might have to get their hands on some extra juice quickly. The government's ability to order more power, however, had greatly diminished in the past two years.

Since the law deregulating the sale of energy took effect March 31, 1998, the government had lost much of its supervision of the production of power. Meanwhile, utilities such as PG&E had been selling off their old power plants to private companies.

Deregulation was predicated on the idea that businesses would jump at the chance to build plants in a newly competitive atmosphere. Lawmakers promised that not only would consumers get more reliable electric supplies but that competition would make the supplies cheaper as well.

But problems were emerging.

Aging plants vulnerable

Some companies were reluctant to build plants until they knew the new market was sound. Those that did try to build them often were opposed by environmentalists and neighbors. And although many new plants had been proposed, getting them built could take years.

In addition, while the government once had a lot to say about the way power plants were maintained so that their power would be available in emergencies, that also had changed.

More than half of California's plants are at least 30 years old. Many are prone to breakdowns. On June 14, nine were shut down or operating at limited capacity. The plants at Moss Landing and San Francisco's Hunter's Point had suffered unexpected mechanical failures. Seven others were undergoing scheduled maintenance.

Another concern among consumers and public officials was whether some power companies were manipulating electricity supplies to influence the price by withholding power until it was needed the most.

``The structure is set up to enable someone to game the system,'' said Loretta Lynch, president of the California Public Utilities Commission, who co-wrote the report.

At noon, a number of Bay Area companies heeded the ISO's request to voluntarily go to backup power. Given how hot it was getting, however, the savings of 500 megawatts was not going to be enough.

San Jose was on its way to hitting 109 degrees, the hottest temperature ever recorded there. Similar records were about to be set in San Francisco and Oakland. The heat caused train tracks to bend, pavement to buckle and traffic signals to malfunction.

Based on the ISO's projections that nearly 95 percent of the state's available power was about to be committed, it issued a ``Stage 1'' alert at 1 p.m., asking consumers statewide to conserve energy.

If the emergency had continued to worsen across the rest of the state, the ISO would have gone to a Stage 2 alert, ordering many more businesses to go on backup power. The next step would have been a Stage 3 -- rolling blackouts in which utilities shut off power anywhere from San Diego to the Oregon border. Ultimately, no such alerts were required because, at least throughout most of the state, the weather was relatively cool and power use modest.

But in the Bay Area, a crisis was looming.

Besides the suffocating weather, the six high-voltage transmission lines feeding into the area weren't enough to handle the local demand. Even if the Bay Area could have received more power from other parts of the state, the transmission system couldn't handle it. The network of lines funneling power from Tracy had become a major source of concern. Just one week earlier, an ISO memorandum warned of trouble there.

``The potential for overloading'' those lines ``has been identified in previous planning studies over the last few years,'' it said, noting that the network had suffered some overloading last summer.

Those transmission lines feed into a tangle of electrical equipment known as the Newark Substation near the southern border between Newark and Fremont. That substation's capacity for power was limited, too. As the substation's lines became increasingly stressed, some of the electricity was being converted to heat and, thus, lost to the system.

That resulted in a steady drop in voltage levels that Jim Detmers, managing director for ISO operations, likened to the effect a large hole has on a backyard sprinkler system.

``If you start losing pressure on that pipe,'' he said, ``eventually you have no pressure to keep the sprinklers going. That pressure is the voltage in the system.''

Because lines carrying power to the entire Bay Area are all connected, a severe drop in pressure at one substation could cause the whole grid to shut down. And if that happened, power could go out throughout the state, officials said.

For the ISO, the situation had deteriorated far enough.

At 1:13 p.m., it ordered PG&E to begin turning off customers' power to save the system, only the second time it had ever done so. The idea was to shed at least 100 megawatts of power use over the next hour or two, primarily in the Bay Area.

PG&E already had a plan in place to do just that. It had divided all 4.5 million of its electricity customers into 14 lists -- or blocks, as it calls them -- with each list using about 850 megawatts. The customers on each list are spread out through PG&E's entire service area. But as the ISO needed to cut only 100 megawatts, PG&E began turning off power to only some of the customers on its first block.

In many cases, said PG&E spokesman Jon Tremayne, ``it is done literally from one of our control centers with the flip of a switch.''

A total of 33,763 homes and businesses were initially affected in Santa Clara, Contra Costa, Alameda, San Mateo and San Francisco counties, although the power was maintained at hospitals and other emergency agencies.

Things moved quickly after that. At 2 p.m., the city of Santa Clara interrupted its own power supplies to some of its customers, saving five megawatts.

Others go out

At 2:30 p.m., PG&E cut electricity to an additional 17,616 of its block-one customers while restoring power to those it had turned off previously. At 3:30 p.m., 45,650 more homes and businesses were hit. By the time the rolling blackouts ended at 4:35 p.m., a total 97,029 homes and businesses had been affected.

The companies that had volunteered to switch to backup power were restored to the grid at 6 p.m., and the Stage 1 alert officially ended two hours later.

But the effects of what happened June 14 are sure to linger.

Just a few years ago, the ready supply of power was taken for granted by most people in the state. But two years into its deregulated energy experiment, California finds itself in a kind of twilight zone.

It is too far along to completely turn back, many energy specialists believe. But it also could be several years before sufficient numbers of new power plants and transmission lines are constructed to make the system whole again.

Until then, no one can be certain when or where the next series of blackouts might strike.

``California's electric system is no longer consistently reliable,'' concluded the report to Davis. And for the foreseeable future, it added, ``there are no simple solutions.''

http://www.sjmercury.com/premium/front/docs/blackout06.htm

-- Martin Thompson (mthom1927@aol.com), August 06, 2000


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