SAN FRANCISCO (CBS SF) — While state power officials were declaring a Stage 3 Alert in mid-August, PG&E officials were sending an errant message to one of their major plants, forcing it to actually cut the flow of electricity into the grid, officials revealed Tuesday.
PG&E released a statement Tuesday, revealing the error.
“During the extraordinary August 15 statewide energy capacity event, PG&E, in response to the California Independent System Operator’s call to bring certain units to full energy output, issued a verbal dispatch order in error to the Panoche Energy Center,” the company said. “The order resulted in the temporary ramping down of Panoche’s energy output by approximately 255MW for a period of less than a half hour. The drop represented roughly 0.5 percent the total CAISO load of 44,913MW for that time period.”
The utility said the plant was quickly brought back to full power. State power officials have not revealed the impact of the short-lived disruption.
“When the error was identified, we corrected it immediately and ordered the plant to return to full generating capacity, where it stayed for the remainder of the day,” PG&E officials said. “In the aftermath of this incident, we have been open and transparent with CAISO about what occurred, informing them of the full details of incident.”
At the time of the plant shutdown, the state power grid was facing a second day of extreme demand as a record heat wave was gripping the state. On Aug. 14, the demand for electricity reached critical levels, triggering the first wave of rolling blackouts since the 2001 energy crisis.
Thousands of San Francisco Bay Area homes and businesses went dark for an hour or more. On Aug. 15 they faced a similar threat, but the rolling blackouts were cancelled at the last minute.
However, PG&E did impose rolling blackouts to approximately 220,000 customers in portions of the Central Coast and Central Valley including Monterey, Santa Cruz and San Joaquin counties.
The roller-coaster ride was triggered by a stifling heat wave that blanketed California with triple digit temperatures and a major demand for electricity to power air conditioners.
Heat records fell in several cities. San Francisco, Salinas and dozens of other Bay Area cities had record highs. Palm Springs hit 120, breaking a 2015 record by several degrees.