Pacific Gas & Electric found 328 cases of damage or hazards on its system after it conducted public-safety power shut-offs in late October, it told state regulators Nov. 18, in a filing made alongside reports from other utilities.
PG&E conducted the outages on Oct. 26 and 29 due to high winds, affecting about 941,000 unique customers over the course of the two events, it told the California Public Utilities Commission. The outages were longer than previous ones, as the overlap of two high-wind events led to overlapping cycles of de-energization, PG&E said in its report.
"Customers in scope for both events experienced a cycle of either being de-energized and restored for a short period of time, and then de-energized again, or being de-energized and remaining de-energized over the duration of both events," PG&E said. "The average customer outage duration for the combined events was approximately 55 hours."
PG&E said initial areas highlighted for further improvement include enhancing scoping ability; increasing the accuracy of data, estimated restoration times and precision; improving map precision; optimizing external communication; and addressing emergency operations-center staff fatigue.
Southern California Edison said that on Oct. 27, proactive de-energization was required for 126 circuits, including three transmission lines, and about 127,000 customers were affected.
"During the incident, SCE notified public safety partners, critical infrastructure providers, local governments, elected officials, and customers in areas under consideration for PSPS. However, due to rapidly changing weather conditions on October 27 and 28, some circuits not in their respective periods of concern for potential PSPS had to be immediately de-energized," the utility said in its filing.
San Diego Gas & Electric in its filing said it activated its emergency operations center in response to three high-fire-threat weather events, on Oct. 20-22, Oct. 24-26, and Oct. 28-Nov. 1.
"SDG&E treated each weather event as a separate occurrence regarding notifications to customers, external agencies and public safety partners," the utility said. SDG&E in its filing said about 48,000 customer accounts had their power cut over three weather events in October.