Spearmint Energy receives permit for 600MWh Minnesota BESS

July 21, 2026

The preliminary design also incorporated a modular layout of enclosures based on Tesla’s Megapack 2XL lithium iron phosphate (LFP) BESS solution. Image: Spearmint Energy via YouTube

Battery storage developer-operator Spearmint Energy has received a site permit for the 150MW/600MWh Midwater Energy Storage Project, in Freeborn County, Minnesota, US.

Announced 16 July, Spearmint received a site permit for the battery energy storage system (BESS) project from the Minnesota Public Utilities Commission (MPUC). It will be sited on 10 to 20 acres of privately owned land adjacent to the Glenworth Substation off Minnesota Highway 65 in Freeborn County.

Midwater is Spearmint’s second project to advance through Minnesota’s state permitting process, following the successful permitting of the company’s 150MW/600MWh Snowshoe Energy Storage Project in Olmsted County, in 2025, which was the first standalone battery storage project approved in the state.