
Warren Buffett’s Berkshire Hathaway-owned BHE Montana has successfully energised its 75MW/150MWh Glacier Battery System project in Montana, US.
The battery energy storage system (BESS) is located near Cut Bank, Montana. BHE says it represents a US$100 million investment, providing “critical grid support” and enhancing “reliability across the region”.
The project supports BHE Montana’s participation in the Western Energy Imbalance Market (WEIM), established in 2014.
WEIM extends the California Independent System Operator’s (CAISO’s) real-time market to areas in California, Arizona, New Mexico, Texas, Oregon, Washington, Nevada, Idaho, Montana, Utah, and Wyoming, with more joining. Participants, including CAISO, benefit from economic, operational, and environmental advantages by trading energy across a large area in real time.
Try Premium for just $1
- Full premium access for the first month at only $1
- Converts to an annual rate after 30 days unless cancelled
- Cancel anytime during the trial period
Premium Benefits
- Expert industry analysis and interviews
- Digital access to PV Tech Power journal
- Exclusive event discounts
Or get the full Premium subscription right away
Or continue reading this article for free
The US Energy Information Administration (EIA) reports that Montana possesses significant renewable energy resources and was ranked 10th highest in 2024 for the proportion of electricity produced from renewables among US states.
Hydropower and wind accounted for approximately 57% of the state’s electricity generation. Notably, wind energy powers three of Montana’s 10 largest generating plants by capacity and annual generation.
The state’s solar generation is relatively small by comparison, however, generating approximately 2% of Montana’s in-state generation in 2024.
Also from the US EIA, in 2005, Montana established a renewable portfolio standard (RPS) requiring retail electricity providers to source at least 15% of their in-state sales from renewable energy by 2015.
The state met and surpassed this goal by 2015, leading to the RPS’s repeal in 2021. Montana also offers low-interest loans to households and businesses for energy-saving improvements, such as energy-efficient appliances, windows, and renewable energy systems like solar, geothermal, wind turbines, and low-emission wood stoves.
BHE Montana manages the 189MW Rim Rock wind farm near Kevin, Montana, along with the 105MW Glacier I and 103.5MW Glacier II wind farms located in Glacier and Toole Counties in northern Montana. In October 2025, BHE Montana also began construction of the Glacier Solar Park, a 130MW solar project.
The Energy Storage Summit USA will be held from 24-25 March 2026, in Dallas, TX. It features keynote speeches and panel discussions on topics like FEOC challenges, power demand forecasting, and managing the BESS supply chain. ESN Premium subscribers can get an exclusive discount. For complete information, visit the Energy Storage Summit USA website.