en.Wedoany.com Reported - Spearmint Energy (Spearmint) has secured a site for a 600 MWh battery energy storage facility planned in Freeborn County, Minnesota. The Minnesota Public Utilities Commission previously approved a site permit for the proposed Midwater Energy Storage Project (Midwater). The site plans to install a 150 MW (600 MWh) standalone battery energy storage system (BESS).
The Midwater project will be located on 10 to 20 acres of private land near the Glenworth Substation along Minnesota State Highway 65 in Freeborn County, aiming to support a more reliable, stable, and affordable energy supply. The new facility will act as a large rechargeable battery for the state grid, capable of supplying power to the grid at a maximum rate of 150 MW when needed. The 600 MWh storage capacity means the system, when fully charged, can theoretically provide approximately 4 hours of 150 MW power supply. Its operating principle is similar to home energy storage batteries: charging when electricity is abundant and relatively cheap, such as during peak performance of wind farms, periods of low consumer demand, or when power plant generation exceeds demand; and discharging to the grid when electricity demand rises or supply declines.
The new facility, adjacent to the Glenworth Substation and spanning several acres, enables practical connection to the high-voltage grid. The batteries will be housed in a series of container-sized battery units, equipped with electrical equipment, transformers, fire safety systems, and control infrastructure. This battery energy storage system does not rely on a single power input; it connects directly to the grid and charges or discharges as conditions allow.
Andrew Waranch, Founder, President, and CEO of Spearmint, expressed gratitude to the Minnesota Public Utilities Commission and its staff for their commitment to reviewing the project, stating that the Midwater site permit represents a meaningful investment in the energy future of southern Minnesota. Chief Development Officer Peter Rood noted that battery energy storage systems play a critical role in enhancing grid reliability, storing energy when supply exceeds demand and returning it to the grid when needed. As electricity demand continues to grow, projects like Midwater provide flexible infrastructure that supports grid stability and affordability, and can integrate diverse generation resources. The project has obtained a site permit, but construction still requires subsequent steps such as completing a grid interconnection agreement, financing, and procurement.
