Pacific Gas & Electric filed its state-mandated 2019 wildfire safety plan last week. The $1.5 billion to $2 billion plan proposes to clear vegetation, inspect power lines, install sensors and cameras, and otherwise invest in efforts to prevent a recurrence of the deadly wildfires that pushed the Northern California utility into bankruptcy.
But perhaps the most controversial part of PG&E’s plan (PDF) is to dramatically expand the scope of planned grid outages, which are intended to pre-empt the risk of its grid sparking more deadly wildfires this summer, and the disruptions and dangers those blackouts could cause.
PG&E didn’t specify how many customers could go without power this summer under the expanded “public safety power shutoff” (PSPS) authority it’s seeking from the California Public Utilities Commission. But in its filing last week, the utility warned that while it is planning them only as a “last resort,” it will be “alerting 5.4 million PG&E electric customer premises," or its entire customer base, that they might be facing power outages due to public safety power shutoffs this summer.
To mitigate these effects, the utility has laid out a raft of proposals, from sectionalizing portions of its grid to reducing the scope of outages during PSPS events, to building “resilience zones” — community centers or critical facilities in high-risk areas that can be equipped with grid interconnection hubs to support fast deployment of backup generators. It’s also proposing some novel concepts, like working with non-utility partners to install or utilize on-site generation or distributed energy resources for continuous power during safety outages, and exploring the potential for true microgrid systems to play a role.
But beyond grid sectionalizing and the hopes of enlisting private partners for backup power, most of these next-generation efforts won’t be ready for the 2019 fire season. And PG&E isn’t setting a timeline for some of the emerging technologies it’s testing to reduce fire risk, such as faster detection of potential fire-starting faults, or sensors and analytics to provide real-time “situational awareness” on its distribution grid.
And for customers who may be affected by fire-prevention blackouts this summer, PG&E’s plan proposes relatively few options, beyond working with local first responders and critical services providers in high-risk areas to ensure emergency power is available, and providing up-to-date service restoration information, bill payment relief, and other “customer services and programs” for the rest of those left in the dark.
From thousands to millions: Why PG&E’s PSPS plan could expand so dramatically
California utility San Diego Gas & Electric was the first to get approval from the California Public Utilities Commission for public safety power shutoffs, in response to its deadly 2007 wildfire season. After the deadly Northern California wildfires of 2017, the CPUC extended that authority to PG&E and Southern California Edison. PG&E applied the program last year to cover its distribution system or transmission lines below 115 kilovolts and in areas considered to be at the highest fire risk, according to the CPUC’s newly developed fire map.
In its first use of its PSPS authority, PG&E shut off power for about 60,000 customers in October, a move that sparked widespread complaints and claims of damages from spoiled food, interrupted business, and the like. But in November, it considered but decided against de-energizing power lines. That includes the power line suspected of playing a role in starting the Camp Fire; the utility deemed the risks not great enough.
Amid PG&E’s slide into bankruptcy, its safety record and its use of PSPS came under the scrutiny of U.S. District Court Judge William Alsup, who oversees PG&E’s criminal probation for its role in the San Bruno disaster. Alsup is now considering ordering PG&E to pre-emptively shut off grid power under a far more restrictive set of wind and weather conditions. That proposal has been opposed by the CPUC, on the grounds that it would pre-empt its own authority on the issue, and potentially force PG&E into grid outages that could cause more dangers than they prevent.
PG&E’s new PSPS plan would expand on its old plan in three key ways. First, it would cover not only the Tier 3 “extreme” fire risk areas on the CPUC’s fire map, but the Tier 2 “elevated” fire risk areas as well. This is a huge expansion of territory, from a relative handful of pockets to more than half of PG&E’s service territory. It would also increase PG&E’s targeted distribution lines from about 7,000 circuit miles to about 25,200 circuit miles.
This version of the CPUC’s fire map shows Tier 3 areas in red and Tier 2 areas in yellow, highlighting the increase in territory.
Second, PG&E would include high-voltage transmission lines as targets for de-energization, expanding the range of the targeted transmission lines from approximately 370 circuit miles today to approximately 5,500 circuit miles. That’s not only a big expansion in territory, but it also opens the potential for PG&E’s decisions to force parts of the grid far away from the high-risk target areas to lose power.
Third, “PG&E is further evaluating its PSPS decision criteria to reduce the level of judgment in the criteria to the extent feasible." Or, in other words, it’s planning to decrease the threshold for shutting off power. PG&E’s plan lays out many of the data points it uses to calculate these thresholds, including the most granular and up-to-date data possible on weather, wind, humidity and susceptibility of vegetation to catch fire, as well as an analysis of where its grid has experienced fire-causing faults in the past.
But PG&E’s plan doesn’t provide much detail on just how its new thresholds differ from the old one, Michael Wara, the head of Stanford University’s Climate and Energy Policy Program and one of five members of Gov. Gavin Newsom’s Wildfires Blue Ribbon Commission, noted in a series of tweets this week.
“First and foremost, what level of risk is PG&E targeting? What was the basis for setting the thresholds at the new level?” he wrote.
“Second, how often are the thresholds likely to be exceeded in PG&E service territories,” either in terms of applying them retroactively to the 2017 and 2018 fire seasons, or comparing them to the old thresholds, he asked.
Finally, Wara questioned how shutting off transmission lines could conflict with operations of state grid operator CAISO, or run afoul of the federal regulations governing transmission systems.
Reducing the pubic impact: New grid gear and wildfire resilience zones
While most of PG&E’s fire safety budget is tied up in its massive tree-clearing and grid-inspection plans, it’s also planning to invest in grid technologies to both reduce the risk of starting fires, and to manage the impacts of fire-prevention power shutoffs. First among these is a broad effort to upgrade its distribution grids in Tier 2 and 3 areas with SCADA-enabled reclosers, or devices that can isolate sections of feeders during outages or overload conditions, thus limiting the number of customers affected.
PG&E’s work on this front is partly driven by its need to replace or disable reclosers that aren’t already SCADA-connected, and thus able to be turned off at times of high fire risk. That’s because automated reclosers can actually cause sparks if they blindly try to re-energize a downed line, which can be a major fire hazard. Of the 2,800 reclosers in Tier 2 or 3 areas, about 2,100 were SCADA equipped at the end of 2018, and PG&E expected to have the rest networked by June.
But PG&E also plans to deploy additional line reclosers at the boundaries of Tier 2 and 3 areas “in an effort to further sectionalize distribution circuits and limit the duration as well as the number of customers impacted by PSPS events,” it wrote. While it doesn’t provide details on this work, it indicates that it would continue over the next five years, noting a long list of sectionalizing opportunities that won’t be ready to mitigate impacts during this summer’s fire season.
PG&E’s second effort is more forward-thinking, but will take much longer to have a real-world impact, at least outside its first pilot location. That’s the concept of “resilience zones,” which could extend emergency backup power to services such as grocery stores and gas stations in areas suffering from a PSPS. The prep work includes preconfiguring segments of the distribution system that can be quickly isolated from the broader grid, and preinstalled interconnection hubs (a transformer and associated interconnection equipment, ground grid, and grid isolation and protection devices) where PG&E can connect “temporary mobile generation” to energize the area.
PG&E launched its first resilience zone pilot last March with Pacific Union College in the Napa County town of Angwin, where it’s expected to provide backup power to centrally located facilities such as the fire station and gas station, as well as nearby apartments and stores not served by the cogeneration plant that powers much of the campus. That system “will operate as needed during 2019’s wildfire season,” and serve as a test for “expanding the Resilience Zone workstream for other towns that may be impacted by PSPS” in the years to come, the plan states.
But the scope of these resilience zones will necessarily be limited to those areas that can’t be helped by other methods — and that don’t present their own risk of sparking fires from their energized grids. PG&E plans to limit resilience zones only to areas where the targeted sectionalizing it’s working on with its SCADA-enabled reclosers isn’t feasible for grid configuration or other reasons, and in areas that have been "sufficiently de-risked of ignition danger through system hardening measures that a temporary mobile generator can safely run during Extreme-Plus conditions.”
Looking ahead: Private partnerships, microgrids
PG&E’s fire safety plan only mentions the concept of microgrids briefly. It notes that the preinstalled interconnection hubs it plans to install for mobile generators at resilience zones “may evolve into Resilience Zone Microgrids over time, as preferred resource combinations begin to meet technical requirements, and as PG&E’s capability to operate these systems matures.”
It also mentions the possible value of customer-owned microgrids, although it doesn’t provide much concrete guidance: “The ability to island (to disconnect completely from the centralized grid) at key times can allow for sustained backup generation to critical facilities in communities working to respond and recover from wildfires and other natural disasters. PG&E is continuing to explore various paths to meet customer needs (resilience and other), as well as opportunities to support quicker recovery after a PSPS event is called.”
But PG&E does plan to explore some novel efforts to bring backup power to its customers, Stanford's Wara noted. For example, the utility is considering a plan to “partner with major retailers and equipment suppliers to support onsite backup generation systems that can provide continuous power during a PSPS event." PG&E would not be the owner-operator of the gear, but would help to ensure the system is installed and operated in a way that can also help during an emergency event.
"You don't typically see IOUs proposing those sort of things in PUC filings," Stanford's Wara noted. But, as with its proposal to change its methodology for determining when to institute a fire safety power shutoff, PG&E's plans for working with outside parties to provide backup power are still lacking in critical details.
PG&E does provide more detail on how it will work with customers, communities, first responders and firefighters to prepare for public safety power shutoffs. That includes providing as much advance warning as possible before de-energizations, organizing community "enhanced cooling centers" to shelter people left without air conditioning during heat waves, and setting up emergency operational plans with critical services providers in affected areas.
PG&E wasn't the only utility to file a fire safety plan last week — the CPUC accepted other plans from SCE and SDG&E, as well as four other utilities and transmission companies operating in the state. But PG&E's plan will doubtless come under much closer scrutiny from state lawmakers and regulators, as well as judges overseeing its bankruptcy proceeding and criminal probation, and other stakeholders demanding extraordinary steps to prevent more deadly wildfires.
The CPUC will hold workshops on the plans on Feb. 26 and 27 and will begin accepting comments in March.