The grid moves underground

Scrolling through my newsfeed this morning, I came across and excellent article at Inside Climate News on the issue of burying power lines in North America. I think it's probably the most comprehensive mainstream article on the topic that I've ever read. The author gives a thorough run down on the advantages and disadvantages of underground lines, the alternatives, and why it all matters more than ever. 

The author explains that the debate over burying lines is heating up because of our changing climate: 

"Across the U.S., wildfires are increasing both in frequency and intensity, a trend expected to accelerate with climate change. Core fire seasons are on average 78 days longer than they were in the 1970s, according to theColorado Division of Fire Prevention and Control’s 2022 Wildfire Preparedness Plan. This can push the wildfire season into historically windy times, often to catastrophic effect, Colorado State Climatologist Russ Schumacher recently told the state Public Utilities Commission. And destructive blazes aren’t isolated to rural wildlands, but are also burning in suburban grasslands, as with the Marshall Fire. As development sprawls into flammable landscapes, humans become their primary fire starters, including from the widening web of power lines."

"The debate over burying power lines is going on across the country as extreme weather batters above-ground electricity transmission equipment, and rapidly expanding populations overtax the capacity of aging infrastructure. According to the National Interagency Fire Center, from 1992 to 2020 federal, state and local fire services dealt with 32,652 powerline-ignited wildfires across the country. Without mitigation of power lines’ potential to start fires, those numbers are sure to grow, as fighting climate change has sparked a movement to “electrifying everything,” which requires a rapid expansion of power distribution networks."

Burying lines is the most effective mitigation solution, but also the most expensive:

"While burying power lines can almost eliminate their potential to start fires, it’s an expensive solution, with costs of millions of dollars a mile that are passed on to consumers. That makes the solution a hard pill to swallow for utility companies, residents and public utility commissions. And undergrounding can be slow, with utility corridors crossing various jurisdictions, including public lands where federal reviews can delay and even stymie projects."

The upfront costs are what make even the utilities most vulnerable to fires reluctant to pursue a completely underground grid. 

Take PG&E, for example. Earlier this year, the utility revealed details about their push to bury the California grid. According to Bloomberg, the power company wants to put 3,600 miles of transmission lines underground over the next five years. Moreover, the utility is aiming to cut the cost per mile from $3.75 million to $2.5 million in 2026. The 3,600 miles of proposed line are part of a larger effort to bury 10,000 miles of lines by a later date.

While few would claim that PG&E’s underground plan is negative, many wonder if it’s sufficient. In total, PG&E has 25,000 miles of overhead lines in high-threat fire areas. As the plan stands, only 3,600 miles will be underground by 2026, and then 10,000 miles later on. In 2022, they only aim to bury 175 miles of lines. That’s a lot of waiting time in a state where historic wildfires seem to have become an annual event. And, even if things go as planned, that still leaves a whole lot of risky wire above ground. 

Other utilities, like Xcel, have opted to pursue no burying, despite having overhead lines in risky areas. For them, the costs just don't justify the results.

It will be interesting to see how this story develops over the coming years. A couple more big fires could push utilities to take the plunge, or legislators to force them to. For now, however, it seems we'll be seeing a significantly faster adoption rate than in previous years, but still no comprehensive push.