Xcel Energy proposes to keep operating nuclear plants until early 2050s

 Nuclear Generating Plant is seen
Xcel Energy’s Prairie Island Nuclear Generating Plant is seen from Wakonade Drive in Prairie Island Indian Community in Welch on June 30, 2022
Tom Baker for MPR News 2022

Xcel Energy is proposing to keep operating its two Minnesota nuclear plants until the early 2050s.

In a resource plan filed with state regulators on Thursday, the Minneapolis-based utility also proposed adding new wind and solar energy and battery storage. It also calls for adding more “always available” energy — likely natural gas — to provide backup electricity during times of peak demand.

Ryan Long, president of Xcel in Minnesota, North and South Dakota, said Xcel is on track to reduce its carbon emissions by as much as 88 percent by 2030, from 2005 levels. The utility previously had announced a goal of being carbon-free by 2050. 

“We see this plan as really charting a path towards delivering on that vision,” he said. In addition, a new Minnesota law requires utilities to get 100 percent of their electricity from carbon-free sources by 2040.

In Minnesota, large utilities are required about every two years to file an integrated resource plan, which outlines how they plan to generate electricity for the next 15 years. Xcel is Minnesota’s largest electric utility, serving about 1.3 million customers in the state.

Its latest resource plan calls for extending the life of its two nuclear units at Prairie Island by 20 years, until 2053 and 2054. It wants to extend the Monticello nuclear plant’s license to 2050.

Long said the nuclear plants are critical to providing reliable, carbon-free energy for Xcel’s Upper Midwest customers.

“We’re really confident that they’re positioned well to continue operating and doing so for our customers past 2050,” he said.

New generating facilities

The plan doesn’t change Xcel’s timeline for shuttering its remaining coal plants in Minnesota by 2030. It also calls for adding 3,600 megawatts of new wind and solar facilities and 600 megawatts of battery energy storage.

That includes a planned iron-air battery project in Becker, which will store energy produced by a large solar project Xcel is currently building.

“This is going to be one of the first resource plans where we’re actually proposing to build battery storage in the action period of our plan in the first five years,” Long said. That also could include lithium-ion batteries, he said, although the plan doesn’t specify locations.

Xcel’s plan also calls for adding more so-called dispatchable energy that can backup renewable sources when they’re not available. The utility previously proposed building two natural gas combustion cycle plants in Lyon County and Fargo, N.D.

“We don’t expect them to run very often,” Long said. “They will sit on our system and provide needed energy on the hottest days of the summer and coldest days of the winter, when we really need them for critical reliability.”

Clean energy advocates have supported Xcel’s plans to move away from burning coal toward carbon-free energy sources, such as wind and solar.

“We are very excited to see the larger amount of investment they've proposed in battery storage,” said Isabel Ricker, clean electricity program director with the nonprofit advocacy group Fresh Energy. “That’s a really important tool in our decarbonization toolbox.”

However, some environmental groups have questioned the need for new natural gas plants, which they argue will produce carbon emissions and won’t be needed as clean energy and storage become more affordable.

Ricker said Fresh Energy will be looking into whether Xcel could meet that peak demand with its other gas plants, or through a combination of renewable energy, battery storage and programs that encourage customers to shift their energy use to times when demand isn’t as high.

“The more money we put into a new fossil resource, we’re going to be paying for that for at least 40 years,” Ricker said. “And it might be money we would be better off spending on a carbon-free resource.”

More review

The resources plan requires the approval of the state Public Utilities Commission, after public hearings and extensive review. Extending the licenses of the nuclear plants would also require federal approval.

Whether the aging nuclear plants can continue to operate safely for another three decades is likely to be a point of debate. Also, extending the lives of both plants would require additional long-term storage of radioactive nuclear waste. 

The two units of the Prairie Island plant near Red Wing have been operating since 1973 and 1974.

The Monticello plant, about 40 miles northwest of the Twin Cities, has been operating since 1971. Xcel is already seeking an extension of the plant’s federal license, which is set to expire in 2030.

In Nov. 2022, a broken pipe at the Monticello plant caused a leak of water containing tritium, a mildly radioactive form of hydrogen that occurs naturally in the environment, and also during nuclear power production. The utility didn’t make the leak public until March, although it did notify state and federal officials.

Xcel said the leak may have started a few weeks earlier than it first reported, and released between 750,000 and 900,000 gallons of tritium-tainted water, about double the amount it originally estimated. It temporarily shut down the plant in March to repair the leak. Xcel and state health officials have said there’s no imminent public health risk.