Battery storage developer and operator Spearmint Energy has secured a site permit for the Midwater energy storage project, a 150 MW/600 MWh BESS facility located in Freeborn County, Minnesota, US (Spearmint Energy press release, 16/07/2026).
The site permit for the BESS was granted by the Minnesota Public Utilities Commission (MPUC). The project will occupy between 10 and 20 acres of privately owned land next to the Glenworth Substation, located off Minnesota Highway 65 in Freeborn County.
According to the company, Midwater is the second Spearmint Energy project to progress through Minnesota's state permitting process, following the successful approval of the Snowshoe Energy Storage Project (150 MW/600 MWh) in Olmsted County, which became the state's first stand-alone battery storage project to receive approval.
Spearmint Energy currently operates 350 MW/700 MWh of battery storage capacity in ERCOT (US), while a further 300 MW/600 MWh is under construction. The company also has additional projects under development across the United States.