Beartooth Battery

Additional capacity to generate energy on-demand to meet our Montana customers’ peak demand is critical for reliability. We have three projects to add 325 megawatts from the all-source competitive solicitation Request for Proposals for long-term capacity resources issued in January 2020.

One project is a 20-year contract for the 50-megawatt Beartooth Battery project near Billings, Montana, expected to be online by 2024.

On December 21, 2021, we filed an application with the Montana Public Service Commission for preapproval of the Beartooth Battery agreement as a new capacity resource. This agreement is contingent upon MPSC approval of our application and we anticipate a decision in the fourth quarter of 2022.

Details of Beartooth Battery

Dispatcahble for 4 hours at full discharge

Beartooth Battery will be among the first industrial-sized battery storage projects in Montana. Beartooth Battery will discharge up to 50 megawatts of stored energy for up to 4 hours continuously, or 25 megawatts for up to 8 hours.


In Yellowstone County, Montana

esVolta will build and own Beartooth Energy Storage, a 50-megawatt battery storage facility in Yellowstone County, about 2.5 miles west of the city limits of Billings, south of Grand Avenue.



Beartooth Battery will store excess energy, most often generated by wind, to use when our customers need it the most. 


20-year agreement

Beartooth Energy Storage, LLC will construct and own Beartooth Battery. NorthWestern Energy will have a 20-year agreement for Beartooth Battery.


NorthWestern Energy maintains control

NorthWestern Energy maintains control of charging and discharging the battery.


Seeking PSC approval

NorthWestern Energy is seeking approval from the Montana Public Service Commission for a 20-year storage agreement with Beartooth Battery.


For more information about the project, please contact: