by Jeff St. John
May 16, 2019

Last week, California’s investor-owned utilities launched a media campaign to inform the state’s residents that tens of thousands of them — or perhaps millions, nobody knows for sure — could face hours, or days, without electricity this summer. 

It’s the latest development in a long-running effort, being reluctantly pushed by California regulators, wildfire-liability-bankrupted Pacific Gas & Electric and the state’s other investor-owned utilities, to drastically expand the scope of "public safety power shutoff" (PSPS) events — in other words, de-energizing the grid to prevent it from starting deadly wildfires. 

Most of the attention so far has been on PG&E’s plan, which came with a warning that it could leave its 5 million electric customers without power if it’s forced to power down transmission lines crossing areas of fire risk. That’s a drastic expansion of a program that’s been used at only limited scale before. 

San Diego Gas & Electric, which has invested more than $1.5 billion in state-of-the-art fire prevention technology and programs and has been conducting PSPS events since 2013, has blacked out no more than 20,800 people at a time, for example. Southern California Edison has used its PSPS authority twice, including several days from late December to early January that saw it send out warnings of possible outages to more than 70,000 customers, but de-energizing only one circuit with 34 customers. 

PG&E’s sole de-energization, in October 2018, left about 60,000 people in and around the town of Calistoga without power for two days — a move that drew complaints and damage claims from restaurants, hotels and other businesses. It also likely prevented wildfires from starting, utility inspectors later said.

But the California Public Utilities Commission (CPUC) has expanded the scope of de-energization, both to cover a much broader swath of the state, as this map indicates, and to include high-voltage transmission lines (PDF) whose de-energization could force power outages in far-away areas. 

While SCE and SDG&E haven’t publicly discussed how widespread their de-energizations could be this summer, PG&E’s projection — albeit a worst-case scenario — indicates the potential for forced blackouts at a scale California hasn’t seen since its 2000-2001 energy crisis. 

Balancing risks of widespread outages against risk of wildfires

This has galvanized state lawmakers. Gov. Gavin Newsom’s latest state budget has added $75 million to support customers left without power during PSPS events, including the potential to supply them with backup power during extended outages. 

“It’s happening soon. I’m worried about it. We are all worried about it,” Newsom told reporters at a budget briefing in Sacramento last week. “People’s power could be shut off, not for a day or two, but potentially a week.”

The CPUC’s de-energization guidance to utilities makes clear that they must use it as a last resort and minimize the pubic impacts. 

At the same time, de-energization is going to be a vital tool to prevent another utility-caused wildfire, according to Michael Wara, head of Stanford University’s Climate and Energy Policy Program and one of five members of Gov. Gavin Newsom’s Wildfires Blue Ribbon Commission. 

While utility infrastructure causes only about one in 10 of the state’s wildfires, according to the CPUC, it has been linked to some of the worst, Wara noted. That includes November’s Camp Fire, the state’s deadliest, which state investigators confirmed this week was caused by PG&E transmission lines, and the 2017 Woolsey Fire, which is still under investigation, but which may have been started by SCE equipment. 

And under California's "inverse condemnation" legal doctrine, utilities are liable for damages from fires caused by their equipment, whether or not they’re at fault or negligent — a fact that drove PG&E into bankruptcy, and could threaten SCE or SDG&E with multibillion-dollar liabilities if their equipment starts a major fire. 

Under these conditions, “I think they’re likely to de-energize a lot — and there is likely to be a noticeable public impact,” Wara said. 

But between the worst-case scenario painted by PG&E and the known quantities of past PSPS events — all of them meticulously detailed at the CPUC website — there is a huge amount of uncertainty. 

Predicting the unpredictable 

Simply put, California’s utilities don’t know how often and for how long they’re going to have to de-energize power lines during 2019’s fire season. 

"The most important thing is to know how much this is going to happen — and I just don’t think there’s a way to know," Wara said. 

That’s not just because they’re operating under new, more stringent regulations, across circuits that haven’t been subjected to these fire risk analyses before. It’s also because nobody can predict the weather. The state’s heavy rainfall so far this year presages lots of vegetation growth, and thus more fuel for potential fires. 

And even with the right combination of technology and processes to deal with it, de-energization is an inherently unpredictable practice.

“It is very fluid when we’re in these events,” Michael Schneider, SDG&E vice president of clean transportation and asset management, noted in an interview this week. 

In November, as the Camp Fire raged in Northern California, “We were in just as extreme weather conditions here, but you didn’t hear about it, because we were doing a lot of de-energization,” he said. “And we were doing it in a lot of places we hadn’t done it before, such as coastal areas” with heavier populations than the eastern backcountry regions that are more typically targeted for fire risk, as laid out in its CPUC report (PDF). 

SDG&E is held up as a model for modern utility fire prevention, driven by its response to deadly wildfires in 2007. Beyond a robust tree inspection and clearing regime and replacing more than 14,000 wood poles with fire-resistant steel, SDG&E has installed 16 high-definition cameras on mountaintops to monitor for fires, as well as a network of 177 weather stations with wind speed, humidity and temperature readings every 10 minutes.

This data is assessed by five full-time meteorologists on a round-the-clock basis, and goes into forecasts for the week ahead to plan staffing and operations.

SDG&E has also sectionalized a significant portion of its grid in fire-prone areas, allowing it to minimize the number of people who have to lose power during de-energizations. To support those who must be left without power for extended periods of time, it has set up community resource centers to supply water and food, phone-charging, and the latest outage information.

All of this prior work allowed SDG&E to avoid seeking more money for its 2019 wildfire safety plan, as opposed to PG&E, which is seeking $2.3 billion, and SCE, which has budgeted $582 million.

Both are undertaking efforts similar to SDG&E’s in advance of the coming fire season, as detailed in their wildfire safety plans, now under final review at the CPUC.  

An increasingly necessary last resort

Still, “with the major events last year, we learned a lot more,” Brian D’Agostino, SDG&E director of fire science and climate adaptation, said in an interview.

In fact, the utility ended up cutting power in areas that lie outside the CPUC’s designated high-risk fire areas, due to its understanding of the danger of record-high 40-mph winds in an area where distribution lines run through eucalyptus groves.

We actually have to install more weather stations, and do some more engineering on the system, because there are some areas where we feel more situational awareness would help,” D'Agostino said. “We’re always working on situational awareness, tree-trimming, updating our operational procedures, building the weather network […] It’s when all of those mitigations aren’t enough, and the risk is so extreme, that we have to de-energize the system.” 

Bill Chiu, SCE’s managing director of grid modernization and resiliency, said in an interview last week that the majority of its distribution circuits in high fire-risk area are able to be sectionalized, and more are being added this year. Still, “it’s really hard to say exactly how this will play out,” in terms of being able to limit the scope of de-energizations this year.

“It all depends on how wide a swath of area is impacted by weather conditions.”

As for PG&E, it told the CPUC last month that it might not be able to hit all its brush-clearing and line-inspection targets by the start of this summer’s fire season. The utility reported it had completed only about 25 percent of its system hardening and vegetation management work, and had installed only 40 percent of its weather stations, and 70 percent of the cameras called for in its wildfire safety plan.

It’s also working to replace the roughly half of the 1,400 distribution grid reclosers in fire-risk areas area that can’t already be remotely sectionalized during de-energization events. 

It’s possible that some of PG&E’s worst-case scenarios involving multimillion customer blackouts won’t come to pass, if inspections and repairs of high-voltage transmission lines can be completed in time to secure them for this year’s wildfire season, Wara noted. “For those kinds of lines, the solution is not blacking out San Francisco. The solution is to do enough emergency maintenance on these lines so that they can withstand a hurricane.” 

But down in the distribution system, where the vast majority of de-energizations occur, the variables are far more complex and out of utility control, he said. In those circumstances, all the technology improvements available may end up playing a secondary role to de-energization as a primary tactic to manage the risk of grid-sparked wildfires. 

“If you look at what SDG&E has done, de-energization is the action that has prevented wildfires,” Wara said. “They’ve done all those other things, but most of those other things have been to target de-energization when it’s needed, and minimize unnecessary impacts.” 

What to do when the power goes out 

California’s utilities are engaged in a number of efforts to provide an alternative to grid power for communities that will be affected by their de-energization schemes this summer. Some are further ahead than others. 

In its February wildfire safety plan, PG&E proposed a “resilience zone” pilot — a preconfigured section of grid that can be isolated and powered by generators, batteries or other mobile resources — in the Sonoma County town of Angwin.

But last month, it revealed the project has undergone design changes that require it “to obtain additional land rights, which may delay the completion of construction” past its previous June 1 deadline. Specifically, PG&E found it needed to “convert the majority of the existing wire on wood poles to underground distribution lines,” presumably so that the energized microgrid would not create its own fire hazard. 

SCE has detailed some plans for this summer, including a pilot with two high schools to serve as “clean, partial microgrids" during outages to serve their communities, and “community outreach vehicles,” vans and trucks equipped with battery-powered outlets to charge cellphones and laptops, provide water and snacks, and disseminate the latest outage and safety updates. 

SDG&E already has its aforementioned community support systems in place for de-energization event. But for future years, SDG&E is working on a multi-community microgrid project, with up to 100 megawatts of batteries to be deployed in 10- to 30-megawatt increments to power community centers through outages, Schneider said. 

This project, enabled by 2016 state law AB 2868, has already gone through competitive bidding and picked contractors for three of its seven sites, and could see construction on the first projects completed by next summer, although a pending decision by the CPUC could delay that timeline. 

Amid these utility efforts, solar-storage providers such as Sunrun have proposed pilot projects that could see customer-owned systems linked into broader utility resilience plans. But the most likely short-term solution for homes and businesses this fire season will likely be diesel or natural-gas-fired backup generators, which certainly don’t fit into California’s broader clean energy and carbon reduction goals.  

As the CPUC’s de-energization proposed decision points out, these efforts are part of a broader statewide effort to provide distributed energy amid natural disasters. Utilities, as well as the communities they serve, must “treat de-energization in a similar manner as any other emergency that results in loss of power, such as earthquakes, floods or non-utility caused fire events.” 

In that light, everyone who lives in wildfire country in California, which is something like 20 percent of the state, needs to be thinking about this problem as something they need to solve,” Wara said.

“It’s not going to be something that the utility can really solve for them in the near term.”