Commission grills PG&E on power shutoff policies, improvements

PG&E faced questions and criticism about its power shutoff policies during a public briefing Tuesday with the California Public Utilities Commission.

The briefing was the third in a series of meetings with California electricity companies to discuss their efforts to reduce the frequency and impact of what PG&E calls Public Safety Power Shutoffs, or PSPS events.

During the meeting, PG&E presented its 2021 progress and fielded questions from CPUC commissioners, residents and officials from Cal Fire, the California Governor’s Office of Emergency Services and the California Office of Energy Infrastructure Safety.

Throughout the briefing, CPUC President Marybel Batjer pressed PG&E’s senior vice president and chief risk officer Sumeet Singh on specifics of PG&E’s work to limit the number and scope of PSPS events, stressing the commission’s position that shutting off energy to customers should be an absolute last result.

She said:

“Unlike other mitigation strategies, these PSPS events have very real and very direct impacts to customers. It is trading individual risk to customers for reducing wildfire risk. … At risk in a PSPS event are people’s lives and their livelihoods.”

Previously, PG&E based their PSPS decision-making on the likelihood of a large fire happening due to factors like wind speed, low humidity and nearby dry fuel. Singh told the group PG&E is now using updated guidance and new machine modeling in determining when to resort to to a PSPS event. 

The updated modeling incorporates historical weather data and local outage trends to determine the likelihood of igniting a catastrophic fire. It also allows the utility to determine the likelihood that trees will fall on to power lines, potentially causing a fire.

In April, a federal judge overseeing PG&E’s criminal probation recommended the utility do exactly that: take into account what PG&E now calls their “tree overstrike criteria” when deciding whether to schedule a PSPS event. According to Singh, the new criteria would have reduced the number of PSPS events occurring between 2017 and 2019, though the number of events in 2020 would have stayed the same.

The utility was placed on probation in 2016 after a federal court found that PG&E neglected to keep accurate and complete records or address potential threats in its natural gas pipelines leading up to a 2010 fatal gas pipeline explosion in San Bruno.

Incorporating the tree overstrike factor is predicted to marginally increase the average event duration from about 35 to about 39 hours, according to Singh. It’s also expected to slightly increase frequency of PSPS events in eastern and rural areas that have more tall trees, such as Placer County and Butte County, a factor Batjer worries could further hurt underserved communities in those areas.

Moving forward, Singh said PG&E will only consider a shutoff to be necessary if there is both a high probability of an outage and ignition, and a high probability that the ignition grows into a catastrophic fire. For example, a strong windstorm in an area with a lot of dry vegetation would present high probability of both factors.

Meeting just one of those criteria — such as a storm that isn’t dry or a hot day without wind — are not considered likely to cause a catastrophic fire conditions under PG&E’s updated guidance.

Singh also reviewed PG&E’s progress in updating the utility’s power grids and expanded resources for customers impacted by shutoffs.

The utility has installed in excess of 1,000 sectionalizing devices that allow isolation of small grid portions during shutoffs. They have also strengthened more than 600 miles of electrical lines by reinforcing poles and covering the lines.

Hardening measures don’t eliminate the possibility of a PSPS event but raise the threshold at which PG&E will consider a shutoff necessary. The only measure that can completely erase the risk of sparking a wildfire is burying electrical lines underground, Singh said.

Late last month, PG&E announced a new initiative to bury about 10,000 miles of power lines in areas where there is a high threat of fire.

In response to customer feedback, Singh said PG&E has also improved its PSPS event notifications and restoration time forecasting, and has expanded partnerships with community-based organizations to distribute resources such as batteries and meals. The utility says a team of tribal liaisons conduct outreach and provide support for local tribes during PSPS events.

Commissioners pushed the utility on what happens when batteries run out of power or don’t work, to which Vanessa Bryan, PG&E’s senior manager of PSPS customer engagement and strategy, said PG&E relies on community-based organizations that it has connected with to replace batteries.

With several parts of Northern California currently under Red Flag Warnings for weather that could spark a wildfire, Cal Fire Assistant Deputy Director Daniel Berlant noted the timeliness of the briefing with PG&E.

Berlant stressed the importance of improvements and preparedness as California’s wildfire season continues to rage on.

He said in the meeting:

“With nearly 89 percent of California under extreme or exceptional drought conditions, our fire activity across much of the state is going to be extreme, as it already has been this year. … This year’s fire season, if anything like last, is going to go late into the fall, and even potentially into what is traditionally wintertime. The need for PG&E and everybody else to be prepared year-round is only exacerbated.”