(FOX 9) – More than two-thirds of utility poles everywhere Minnesota they are at least half a century old and records show their failure rate increases dramatically with age, a problem exacerbated by climate change, experts said.

These realities have led Xcel Energy to step up its efforts to routinely inspect and occasionally replace aging equipment before it fails. Xcel has about 500,000 poles nationwide, with an average age of 54 years, four years past what the company considers its “useful life.”

“Age is not that important in determining what needs to be replaced or not,” said Michael Lamb, senior vice president at Xcel Energy. “We’ve been building assets for decades.”

Context

Although the utility aims for equipment to last decades, they don’t always make it that long.

After poles reach 40 years, records show that the failure rate increases and continues to do so every decade. The biggest jump occurs when they are between 60 and 70, when the failure rate nearly triples from just over five percent to more than 15.

“You would be looking at things that could fail suddenly. They could fail quickly,” said Dr. Mahmoud Kabalan, director of the Microgrid Research Center at the University of St. Thomas of St. Paul.

Kabalan said the aging network poses threats that are difficult to predict, especially with more severe weather than we’ve experienced in recent decades.

“Once they get old beyond a certain limit, a big storm could take them out,” he said. “You just don’t know when it fails. It could remain operational and meet specifications, but a big storm — a big ice storm — or high winds could cause those poles to fail.”

The changing weather

Experts said climate change is the singular threat facing the power grid, both in Minnesota and nationally.

“As weather events become more severe, outages increase with it,” Kabalan said. “So there is a strong correlation between severe weather and outages.”

Lamb agreed that severe weather remains a significant threat to the grid.

“Climate change is a big challenge that we need to prepare for,” he said.

There is at least one solution to weather-related outages, but it has considerable drawbacks.

Why not put more wires underground?

At the Oct. 1 vice presidential debate, Gov. Tim Walz asked during a discussion about infrastructure, “How do we make sure we protect ourselves by burying power lines?”

Although it is possible to put them underground, it is not practical in most cases because the cost is too great for most consumers.

Xcel said undergrounding overhead lines can cost up to $500,000 per mile in suburban neighborhoods and $5 million per mile in urban areas.

“It’s not only expensive for the utility — which ultimately goes into our price — it’s also expensive for our homeowners,” Lamb said.

He also pointed out that buried lines are not immune to outages and often take longer to repair.

Xcel routinely inspects and replaces its poles if necessary. The utility deploys technicians on the ground and flies drones to inspect them from any angle. In 2023, it inspected nearly 56,000 of its 500,000 poles, replacing 11 percent of them.

Xcel announced Thursday that it will invest $13.2 billion between 2025 and 2030 in the region that includes Minnesota, North Dakota and South Dakota, more than half of which will go toward upgrading its aging transmission and distribution systems there . In addition, Xcel secured a $100 million federal grant from the U.S. Department of Energy, which it plans to use to fund a pole-top strengthening effort as part of a program expected to be launched in late 2024.

“It’s in our DNA to keep the lights on for our customers, and we really feel their frustration when they walk out,” Lamb said.