Why burying power lines is an efficient, but very expensive way to prevent wildfires

As lethal wildfires have destroyed communities from California to Maui, the nation’s largest utility, Pacific Gas and Electric, is making headway on its bold aim to transfer 10,000 miles of power lines in fire-prone areas underground, which might tremendously scale back ignition danger.

“We’re coming off of a historic drought and people circumstances are materially totally different than the circumstances that we noticed simply 10 brief years in the past. And so now is completely the correct time to be taking daring, decisive motion with regard to the grid security,” stated Jamie Martin, PG&E’s vice chairman of undergrounding.

Five years in the past, PG&E’s gear sparked the lethal Camp Fire, which destroyed the city of Paradise, California, and killed 85 individuals. The massive liabilities drove the utility into bankruptcy, from which it emerged in 2020. But only a yr later, in the identical county, PG&E’s gear started another catastrophic fire, prompting the utility to announce its extensive undergrounding plan. The utility has undergrounded 350 miles of power lines to date this yr, and greater than 600 miles since 2021.

While Martin says shifting power lines underground reduces ignition danger by 98%, it comes at a steep price. Data compiled by the California Public Utilities Commission reveals that undergrounding only one mile costs anywhere between $1.85 million and $6.1 million, which means PG&E’s whole plan would doubtless be within the tens of billions. The invoice could be footed by PG&E’s prospects, who already face a number of the highest charges within the nation.

“If we maintain pushing up electrical energy charges, essentially the most susceptible of us should not going to have the opportunity to pay,” says Katy Morsony, a employees legal professional with The Utility Reform Network, a shopper advocacy group that helps a extra restricted method to undergrounding.

Since PG&E earns a assured charge of return on capital investments, the utility is inherently incentivized to undertake extra expensive infrastructure tasks similar to undergrounding, defined Morsony and Daniel Kirschen, a professor of power and vitality techniques on the University of Washington. This is how the utility makes cash, not by promoting electrical energy or gasoline.

“Undergrounding […] prices some huge cash. It’s a big funding. So that may enhance the income that the utilities accumulate,” Kirschen explains. “Now, the query is would these different options be as efficient as these huge funding tasks? That’s the place the regulators have to step in.”

PG&E stated in a press release that, “In the case of undergrounding, our buyers’ priorities are aligned with these of our prospects and our security regulators.”

Although it is expensive, burying power lines is not new. It’s widespread apply in metropolis facilities, the place overhead lines could be obstructive, and extra widespread in Europe general, the place cities are denser. Only about 18% of distribution lines in the U.S. are underground, although for each security and aesthetic causes, as we speak nearly all new lines which are constructed are buried. 

PG&E at present has about 27,000 miles of power lines underground, but these are usually not in areas of excessive wildfire danger. So throughout storms, when excessive winds may trigger a line to topple over or a tree to fall onto a line, utilities have few good choices.

“So one choice is to primarily simply shut down the power line, as a result of if there is no voltage and no present on the road, there is no probability of this launch of vitality taking place after which there is no probability of an ignition,” explains Line Roald, an affiliate professor on the University of Wisconsin-Madison whose work contains modeling the chance of wildfire ignition and power outages within the electrical grid.

Indeed, PG&E has been implementing Public Safety Power Shutoffs in California since 2019, affecting thousands and thousands of individuals. Hawaiian Electric, the utility that could possibly be discovered chargeable for the Maui wildfires that killed at the least 98 individuals, has been criticized for not shutting off power prematurely of excessive wind warnings. If the corporate is decided to be at fault, it does not have practically sufficient cash to repay residents’ injury claims. 

Looked at this way, undergrounding is undoubtedly cheaper than coping with the large prices of lethal wildfires, and fewer disruptive than shutting off power utterly.

“So for this one-time capital funding, we’re primarily eliminating the chance of ignition from an overhead power line by putting it underground,” Martin says.

PG&E is not the one utility that is . San Diego Gas & Electric has a plan to underground about 1,450 miles of power lines by 2031, whereas Florida Power and Light is undergrounding choose lines for hurricane safety. Austin Energy is additionally exploring undergrounding within the wake of a winter ice storm that triggered weeks-long outages, and the federal government has pledged to provide $95 million to Maui to harden its electrical grid, work that could include undergrounding lines.

But the CPUC has since released two cheaper, alternate proposals for consideration, which tremendously reduce on undergrounding. One requires shifting simply 200 miles underground and insulating 1,800 miles with lined conductors by 2026, whereas the opposite entails undergrounding 973 miles and insulating 1,027 miles.

Both proposals would lower your expenses but would in the end put PG&E’s 10,000 mile aim in jeopardy. Plus, PG&E says that insulating lines is solely about 65% efficient at decreasing wildfire danger, far much less efficient than undergrounding.

“If a tree falls on a line, the road is going to break and you are still going to have a danger of a spark and you continue to have an opportunity of beginning a wildfire, even when the road is insulated,” explains Kirschen.

The Utility Reform Network helps the plan to underground 200 miles, and estimates the price of insulation to be about $800,000 per mile, as in contrast with the $3.3 million per mile that PG&E spent on undergrounding in 2022.

“By relying extra closely on insulated lines, we are able to do the work sooner and we are able to ship that wildfire security extra rapidly to these totally different communities,” Morsony says.

Come November, the CPUC will determine on a path ahead for PG&E, with each wildfire danger and prospects’ utility payments hanging within the stability.

Watch the video to learn more about what it takes to move power lines underground.