Minnesota approves first stand-alone battery system, a key step toward a clean energy future – Austin Daily Herald

By Dan Kraker

MPR News/90.1 FM

Minnesota utility regulators have approved the state’s first stand-alone energy storage project, an important milestone in Minnesota’s effort to transition to producing completely carbon-free electricity.

The Minnesota Public Utilities Commission approved a site permit for the 150-megawatt Snowshoe Energy Storage Project, which will be built on an 18-acre site west of Rochester, near the town of Byron.

The batteries will store excess electricity produced by nearby solar and wind farms, and then discharge the power in times of high demand — for example, when people return home from work and school and fire up air conditioners.

Several battery energy storage systems have been built or approved recently in Minnesota in conjunction with solar energy projects, including a facility approved in July in Faribault County south of Mankato.

But the Snowshoe project, to be built by Spearmint Energy, a battery system developer based in Miami with an office in Eden Prairie in the Twin Cities area, is the first-stand alone battery system to be built in the state that will be connected directly to the electric grid.

“So I think it’s a very important step,” said Will Mullhern, director of electricity at the clean energy advocacy group Fresh Energy. “I think for anyone who looks at what we need to do to achieve a clean energy transition in Minnesota, battery storage is going to be a huge component of it.”

Wind and solar are now often the cheapest way to generate electricity. Lithium-ion battery systems like the Snowshoe Energy project provide a way to store up to four hours of that electricity, and then send it back on to the electric grid when the sun isn’t shining or the wind isn’t blowing, providing affordable electricity to consumers.

That helps smooth fluctuations in energy supply and supports the integration of more renewable energy into Minnesota’s power system. It also enhances reliability, said Mullhern, because the grid operator can call upon a battery system quickly when that electricity is needed.

He expects more battery systems to be built as Minnesota gears up to comply with a recently passed state law requiring 100 percent of the state’s electricity to be produced by carbon-free sources by 2040. “I would expect that this is sort of the tip of the iceberg,” Mullhern said.

Federal tax incentives for battery projects were spared in the recent federal reconciliation bill – also known as the ‘One Big Beautiful Bill’ — although tax credits for wind, solar and other clean energy projects will be quickly phased out. “So we expect that they [battery projects] will continue to be more cost-competitive,” said Mullhern.

More grid-connected battery systems would also reduce the need to build expensive and often-controversial transmission lines, said John Tuma, one of the five PUC commissioners who approved the project’s permit.

“Having to site power lines and putting them in people’s backyards is really annoying for people, and they don’t like it. And so if we can do as many of these as we can to avoid that next big power line, that would be a good thing,” said Tuma.

He anticipates that in periods of high demand, the electric grid operator would first tap into battery systems charged with renewable energy, before calling on natural gas-fired power plants, which while cleaner than coal, still produce carbon dioxide and contribute to climate change.

Tuma said the project near Rochester will look like a “small neighborhood storage facility.” It’s expected to be in service by late 2027.

Minnesota utilities are also experimenting with a different technology called iron-air batteries, which are capable of storing electricity for up to 100 hours – far exceeding the capabilities of traditional lithium batteries.

Great River Energy is expected to bring on line a 1.5 megawatt project later this year. And Xcel Energy is planning a 10 megawatt iron-air battery system in Becker, Minn., next to a large solar plant it’s building to help replace the giant Sherco coal plant.