Oct 25 - The San Diego Union-Tribune

San Diego County came within minutes yesterday afternoon of adding electricity blackouts to the list of woes caused by the wildfires.

At about 2:30 p.m., field crews succeeded in bringing the region's largest electric transmission line, the Southwest Power Link, back into service.

Electricity from that line immediately offset losses from several outages and averted the need to begin rolling blackouts that would have affected 100,000 customers immediately and many more in succeeding waves.

In addition to the electricity it provided, the Southwest Power Link's return to service sparked a loud cheer from the 45 or so employees staffing San Diego Gas & Electric's emergency operations center in Kearny Mesa.

"I'm surprised you didn't hear that cheer in Mission Valley," said Michael Niggli, SDG&E's chief operating officer. "All the effort of our crews and the crews from other areas had put in to restore that line paid off at the absolute best possible moment."

A day earlier, Niggli had estimated that the Southwest line wouldn't be restored until at least late last night. Bringing the line back required the work of crews from SDG&E, Southern California Edison and the Imperial Irrigation District.

Deploying a half-dozen washing rigs, the crews spray-cleaned countless insulators and 70 towers supporting the line. Inspections of the line followed, but there was no certainty that the line was operational until current began flowing.

"We were concerned about defective insulators along the line," Niggli said. "If there were defects, we would have had to find them. We were very fortunate."

While rated to carry up to 1,750 megawatts, Southwest is now providing about 1,000 megawatts, enough electricity to power more than 650,000 homes.

The line runs roughly parallel to Interstate 8 and transports electricity from Mexico and Arizona. It had been knocked out of service by the Harris fire about noon Sunday.

Work to restore the transmission link couldn't begin until flames near the line subsided.

For several days, SDG&E officials had emphasized that they were striking a precarious balance in supplying electricity to the utility's 1.4 million customers. Transmission outages caused by the fires and the shutdown of the San Onofre Nuclear Generating Station had forced the utility, which typically gets about half its power from outside the region, to rely almost exclusively on local electric generation to meet demand.

On the other hand, evacuations and a good public response to calls for conservation had reduced demand.

But early Wednesday afternoon, the balance was upset.

About 2 p.m., a generating unit at the South Bay Power Plant tripped off, removing about 250 megawatts -- enough for about 162,000 homes -- from service.

A series of other problems followed, including the loss of three key north-south lines that pass through Camp Pendleton, which were bringing 300 to 400 megawatts into SDG&E's territory, and a generating unit capable of supplying 30 megawatts.

In order to maintain systemwide reliability and unplanned outages, SDG&E began planning for rolling blackouts. But no sooner had that begun -- "within a minute," Niggli said -- than word came that the Southwest link had been brought back into service, and the cheers erupted.

"No one in our business wants to disconnect customers," he said.

In addition, within a couple of hours the South Bay unit was also back in service, said David Hicks, a spokesman for Dynegy, operator of the South Bay plant.

On Sunday, soon after the start of the wildfire crisis, the blazes led SDG&E to curtail power to more than 100,000 customers. But those reductions lasted less than one hour, SDG&E said.

As of late yesterday, 19,500 customers remained without electricity because of a host of outages around the county caused by the fires. SDG&E and the California Independent System Operator, which oversees electric reliability statewide, credited area residents with a strong response to calls for conservation.

Conservation likely averted other problems around the regional grid, SDG&E officials said.

SDG&E is bracing for the expected return today of tens of thousands of customers to their homes as evacuation orders are lifted. That is likely to boost electricity demand.

"We're not out of the woods yet, but we have a stronger system than anytime since before the fires started," Niggli said.

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