The shuttering of the Sherburne County Generating Station Unit 2 last weekend — the retirement of the biggest coal-fired generator to date in Minnesota — marked a major milestone in Xcel Energy’s goal of delivering 100 percent carbon-free electricity in the state by 2040.
The company plans to close Sherco’s remaining coal-fired units in 2026 and 2030 and close the Allen S. King plant in Oak Park Heights to coal operations in 2028.
What’s next for the plants?
The Sherco site in Becker, Minn., “is central to Xcel Energy’s clean energy transition with investments in solar, battery storage and new transmission lines,” company officials said in a statement Thursday.
The last of the coal-fired units at the Sherco power plant in Becker, Minn., Xcel Energy’s largest plant in size and generating capacity, are scheduled to close in 2030. (AP Photo/St. Cloud Times, Joaquin Siopack)
“We see tremendous potential for the (Sherco) plant site in the Upper Midwest’s energy future,” said Ryan Long, president of Xcel Energy-Minnesota, South Dakota and North Dakota. “Just as we’re taking a phased approach to decommissioning the coal units, we’re building replacement generation in phases to support clean, reliable and affordable energy for our customers.”
Xcel officials have a similar plan for the existing King plant, which in the future will be receiving power from solar installations the company is building in western Wisconsin.
The King plant sits on 140 acres of prime real estate on the St. Croix River, which is protected by the National Wild and Scenic Rivers Act. The plant provides about 28 percent of Oak Park Heights’ tax base. The city, with a population of 4,850, has an annual budget of $6 million.
The King plant, which has been operational since 1968, currently generates 550 megawatts of power — “enough energy to power every home in St. Paul,” said Kevin Coss, a spokesman for the company.
“As we prepare to end coal use at the site at the end of 2028, we will replace its generation with about 650 megawatts of new clean energy from solar or projects that combine solar with energy storage, such as batteries,” Coss said.
Xcel officials expect the projects in western Wisconsin to come online between 2027 and 2029, he said.
The King site “will continue to play an important role even after the coal generation ends,” he said. “We will reuse the grid connections at the site’s existing substation to reliably and cost-effectively provide customers with the carbon-free energy produced at the new installations via a transmission line across the St. Croix River.”
Company officials are planning for environmental remediation to take place at the King plant and “working to determine which, if any, of the existing plant buildings might remain,” Coss said.
“Our focus for the King plant until December 2028 is to operate the plant safely and efficiently, and only when it’s needed,” he said. “Presently, we only run the King plant for about six months out of the year, primarily for stretches of days in summer and winter when its power is still needed.”
Plans call for the King plant’s substation to remain in place to handle the megawatts coming from the Willow River, Wis., area, said Oak Park Heights Mayor Mary McComber. “They may even enlarge the substation to handle that capacity,” she said.
The plant’s 785-foot smokestack is definitely going to come down — and the plant’s 40-acre coal field will be removed, McComber said. McComber hopes some of the smokestack’s bricks can be used as pavers in a possible future park.
King Plant concepts
Xcel officials have been working with a variety of federal, state and local government organizations, as well as conservation, community and business groups, to explore additional future uses for the King site, Coss said.
The King Plant Reuse Advisory Panel, which met in 2020 and 2021, came up with two final development concepts for the site: an industrial reuse plan and a mixed-use development plan.
The mixed-use development concept plan includes “enhanced access to the river, a marina and restaurants that take advantage of the scenic views,” according to the advisory panel’s final report. “It could also include hospitality, a variety of residential choices, walkable retail and service uses, as well as museums and other uses that celebrate the history of the land, both during and before the operation of the King Plant.”
The mixed-use plan “represents a major departure from the past and present industrial use of the property,” the report states. “Many significant challenges would need to be overcome for any version of this concept to be realized. Xcel would need to consent to sell the land. The land would need to be cleaned up and remediated to a much higher and more expensive standard. There may be significant liability and indemnification hurdles to clear.”
McComber said she hopes some sort of mixed-use development can be built at the site to take advantage of the scenic St. Croix River.
Xcel Energy’s Allen S. King power plant is seen in an aerial photo taken Aug. 18, 2021. (John Autey / Pioneer Press)
“The view over the river is beautiful,” she said. “We want it to be a destination point for people to visit. It’s exciting. I’m excited to see where it’s going to go in the next couple of years. By the time of the plant’s retirement, plans should be in place of where it’s going to go from there, to get a vision of the future. It’s exciting to see the city grow like that.”
Xcel has 80 full-time employees at the King plant, and company officials are committed “to a smooth transition” with the retirement of the plant, Coss said. “We have transitioned other coal plants without layoffs and expect to accomplish this again at the King facility.”
Sherco’s solar future
In Becker, adjacent to the Sherco site, Xcel officials are building “the largest solar facility in the Midwest,” company officials said Thursday.
“Construction is underway on the first two phases of the Sherco Solar project, totaling 460 megawatts, while an additional 250-megawatt solar array awaits site permit approval,” officials said in a news release. “Once complete, the combined 710 megawatts would generate enough electricity to power more than 150,000 homes each year on average and fully replace the capacity of the coal-fired Unit 2 that retired Dec. 31.”
Xcel also plans to build a 10-megawatt, 100-hour battery storage facility at the Sherco site as a pilot project. The storage system, developed by Massachusetts-based Form Energy, will allow Xcel to enhance reliability by storing wind and solar power to distribute during periods of lower renewable production.
The company is proposing to build a transmission line that would link “at least 2,000 megawatts of low-cost wind and solar resources in southwest Minnesota to the grid,” company officials said. “By reusing existing grid connections at Sherco, Xcel Energy will make the project cost-effective for customers.”
Sherco Unit 2, built in 1977, will become a “synchronous condenser,” the equipment that manages system stability as more renewable energy comes online.
Xcel Energy expects to accomplish the transition without layoffs.
“There’s a lot of life left at the Sherco site, and our dedicated coworkers will manage the transition over the next decade,” said Michelle Neal, Sherco’s plant director.
Sherco transition jobs
Xcel says the new energy investments at the Sherco site will provide economic benefits including: Read also : Scientists make use of ‘ionic liquids’ to solve one of the main challenges holding back dye-sensitized solar cells — ScienceDaily.
Sherco Solar: Nearly 400 union construction jobs, 18 ongoing operations and maintenance jobs, and an estimated $350 million in local economic benefits through payments to landowners and local governments.
Battery storage: 15 to 20 union construction jobs.
Minnesota Energy Connection: Hundreds of jobs to build the transmission line and new wind and solar resources, and an infrastructure investment of more than $1 billion for the region.