SAN FRANCISCO September 24, 2020 – Pacific Gas and Electric Company (PG&E) has identified more than 80 cases of damage or hazards found on power lines that had been de-energized for public safety due to the recent severe wind event. Any of these could have potentially led to a wildfire had the lines not been turned off during the Public Safety Power Shutoff (PSPS) event that started on Sept. 7, 2020.
Although conducting a PSPS event is a tool of last resort for PG&E, it’s important to understand the goals of the program are to not have electrical equipment start any catastrophic wildfires and to prioritize public and customer safety.
In a report submitted to the California Public Utilities Commission today, PG&E also shared:
- That wind gusts of in excess of 50 mph were recorded at weather stations in 14 different counties in PG&E’s service area, including:
- A 66-mph gust in Butte County
- A 66-mph gust in Sonoma County
- A 62-mph gust in Kern County
- How PG&E’s web site and contact centers successfully provided information to millions of customers without any difficulties or delays
- How 50 Community Resource Centers provided water, bathrooms and device-charging to thousands of customers whose power had been turned off for public safety
- How new weather technology and mitigation measures enabled PG&E to execute a PSPS that affected approximately 50 percent fewer customers than a comparable weather event would have in 2019.
- How PG&E was able to restore electric service to 97% of all customers who could be safely restored on Sept. 9, within 12 daylight hours of the severe weather clearing, and to all customers served by accessible circuits on Sept. 10.
“We have worked diligently to improve Public Safety Power Shutoffs by integrating enhanced weather technology, boosting our coordination with counties and state agencies, and making sure customers get timely and accurate information,” said Michael Lewis, PG&E’s Interim President. “Still, we know turning off the power represents a significant hardship for our customers. Please know that we don’t take this decision lightly, and we will only initiate a PSPS as an option of last resort when severe weather that could cause a wildfire makes it absolutely necessary for public safety.”
PSPS Event Impacted 50 Percent Fewer Customers Than Similar Events in 2019
For 2020, PG&E has been focusing on making PSPS events smaller in size, shorter in duration and smarter for customers. Due to preparation and mitigation strategies, the Sept. 7-10 PSPS event affected approximately 50 percent fewer customers than a comparable de-energization in 2019. This was the result of improved meteorological analytic tools, distribution sectionalizing devices, temporary generation including microgrids and the ability to island the Humboldt Bay Generation Station to provide local power.
This PSPS event was based on a forecast of dry, hot weather with strong winds and dry fuel on the ground that posed significant wildfire risk. After getting notifications starting two days ahead, approximately 172,000 customers in 22 counties had their power turned off for public safety late in the day on Monday, Sept. 7. Once the severe weather subsided, the weather “all clear” was given early on Wednesday, Sept. 9.
After PG&E crews patrolled thousands of miles of transmission and distribution power lines, a necessary step to see if the strong winds had caused damage or tossed hazards such as tree limbs into the lines, more than 97 percent of customers who could take service had been restored by nightfall on Sept. 9.The remaining customers were restored on Thursday, Sept. 10.
Due to unsafe flying conditions caused by smoky conditions and gusty easterly winds, PG&E was unable to use a portion of its helicopter fleet to conduct aerial inspections. In all, approximately 2,700 PG&E personnel participated in restoration work aided by another 300 employees in PG&E’s Emergency Operations Center.
Those inspections revealed more than 80 instances of weather-related damage and hazards in the PSPS-affected areas. This includes 59 instances where PG&E lines or other electric-system components were damaged by vegetation (17) or wind (42). Damages, such as a wire down or a fallen pole, are conditions that occurred during a PSPS event, resulting in necessary repairs or replacement of PG&E assets. Additionally, there were 24 instances where a hazard was found. These, such as a tree limb intertwined in a power line, are conditions that might have caused damage had the line not been de-energized.
Here are some examples of what was found as PG&E crews inspected lines prior to re-energization. If a PSPS had not been executed, these types of damages could have caused potential wildfire ignitions.
- In Concow in Butte County, a tree fell into a wire and knocked it to the ground
- In unincorporated El Dorado County, multiple tree limbs fell on a 21,000-volt power line
- In Colfax in Placer County, a broken crossarm was found that could have resulted in the power line sagging or falling
- In unincorporated Shasta County, a broken pole was found during patrols