City News Service
Last September's historic Southland blackout, which left communities from northern Mexico to Orange County and Arizona without electricity for almost 12 hours, stemmed from inadequate preparedness and subpar coordination among the agencies that operate the region's power systems, according to a government-industry report released today.
The analysis by the Federal Energy Regulatory Commission and the nonprofit North American Electric Reliability Corporation concluded that "effective review and use of information would have helped operators avoid the cascading blackout."
The outage left 2.7 million utility customers across the Southwest without electricity, forcing the closure of schools, offices, government facilities, stores and gas stations throughout the region.
Motorists were stuck on commuter roadways and ran out of fuel in lengthy traffic jams, medically fragile people packed hospitals, and others wound up trapped in elevators and on trolley cars.
In San Diego, the massive blackout also knocked out two city sewer-pump stations, causing spills of about 1.9 million gallons of wastewater into Penasquitos Lagoon, and some 125,000 gallons into Sweetwater Channel.
The outage began about 3:40 p.m. on Sept. 8, when Arizona Public Service's Hassayampa-North Gila 500-kilovolt transmission line went down.
The region's power providers and system overseers proved unable to "ensure reliable operation or prevent cascading outages" following that "single contingency" in the grid, according to the report.
"That line loss itself did not cause the (regional) blackout, but it did initiate a sequence of events that led to the blackout, exposing grid operators' lack of adequate real-time situational awareness of conditions throughout the western interconnection," the document states.
In San Diego Gas & Electric's service area, the falling dominoes-style breakdown of transmission systems knocked all the power out almost simultaneously. "San Diego was essentially gone in 30 seconds," SDG&E President Mike Niggli said this afternoon during a briefing he called to discuss the findings of the report.
In response to reporters' questions, Niggli insisted that the local utility's equipment "worked just as designed" when it went off line to keep the blackout from moving north, into other parts of California.
'So the system's designed to partition itself ... . Our system worked perfectly to partition (the grid) and make sure (the outage) did not spread," Niggli said.
The problem for San Diego County and adjacent areas was that "systems to the east actually sort of collapsed and pulled us with them," he said.
Niggli agreed with the report's conclusion that the operators of the various involved systems lacked what he called "visibility" into each other's moment-to-moment operations and equipment status.
According to the document, "more effective review and use of information would have helped operators avoid" the large-scale crisis.
"For example, had operators reviewed and heeded their real-time contingency analysis results prior to the loss of the APS line, they could have taken corrective actions, such as dispatching additional generation or shedding load, to prevent a cascading outage," the report states.
The eight-month analysis "highlights the growing need for more coordination of grid operations in the West," according to FERC Chairman Jon Wellinghoff.