PG&E works to curtail power outages
By Anne Ward Ernst
NAPA, Calif. — When the public safety power shutoff program began in 2018 there was no telling how many power outages communities would incur. Now Pacific Gas & Electric has reported recently that through advanced technology, situational awareness and other mitigation measures the utility expects the number of proactive outages to continue to decline.
In an Aug. 3 briefing with the California Public Utilities Commission, PG&E representatives told commissioners that several mitigating measures it has taken since the inception of the PSPS program should keep the number of forced outages lower than when the program began.
In 2022 the utility had zero PSPS outages, primarily due to favorable weather conditions, said Dave Canny, senior director of electric program management for PG&E, but weather is unpredictable.
Since the 2018 start of the PSPS program the number of customers impacted by PSPS outages has dropped each year due to several factors, Canny said.
State-mandated vegetation management around the utility’s power lines has helped prevent tree limbs or fallen trees from colliding with power lines. But the utility reported that it has cut its “enhanced” vegetation management and is shifting to two different approaches.
One is the focused tree inspections program, which will center on high-fire-risk areas where there has been a high volume of vegetation damage during previous PSPS events. The other program will use data from outages on enhanced power-line safety setting-enabled circuits.
The enhanced power-line safety setting program is becoming a centerpiece not just for PG&E but other state utilities in mitigating wildfires cause by utility equipment. The EPSS program, which piloted in 2021 and took full effect in 2022, uses sensitivity measures on power lines that will shut off in one-tenth of a second if an object comes into contact.
Napa Valley experienced several shutoffs that came with no warning when the EPSS sensitivity levels were heightened. Now PG&E has installed more than 1,200 “sectionalizers” throughout its service territory — though it is unclear how many are installed in Napa Valley — that separate sections of the grid so that power outages affect smaller numbers of customers.
PG&E also said it has completed some grid-hardening on upper lines as well as undergrounding of power lines. Some exposed lines have been hardened with covered conductors, which reduce the risk of fire if an object hits the power line. Such grid-hardening doesn’t exempt an area from a PSPS though, utility executives said.
PG&E reported that it has completed 39 of 350 miles of planned undergrounding in 2023 and 180 miles in 2022. Overhead hardening completion in 2023 amounts to 79 of 110 planned miles, with 335 miles completed in 2022.
Cal Fire chiefs at the CPUC meetings said that conditions in 2023 are similar to what 2017 incurred — a very wet winter that turned into a very dry summer and fall.
Automation and machine learning are assisting the utilities in forecasting weather, especially wind. More weather stations have been installed to capture data that is being integrated with historical data across the region to help identify trends and patterns that can inform decision-making for PSPS calls.
Utilities are also using automation and other technology to keep customers informed of potential PSPS events and other related activities.
PG&E representatives said the utility continues to learn how to better manage PSPS through feedback from customers and public-safety partners.
Anne Ward Ernst is a journalist who loves covering the Napa Valley.
I absolutely hate the way the trees are cut when the contractor for PGE does it. It looks like they have no training. Two beautiful oaks on Trancas near the Soscol Bridge have been left looking awful. If you trim a tree it should be done all over the tree and not like a v in the middle of it. This unbalances the tree and makes it more likely to fail. That may be the idea.