Berkshire Hathaway Energy Montana Energises 150MWh BESS

Why It Matters

The battery provides critical grid support while unlocking revenue through real‑time energy trading, accelerating Montana’s transition to a low‑carbon, resilient power system.

Key Takeaways

• $100M investment powers 150 MWh battery.
• Enables participation in Western Energy Imbalance Market.
• Boosts grid reliability in renewable‑heavy Montana.
• Complements BHE’s wind farms and upcoming solar park.
• Supports real‑time energy trading across 12 western states.

Pulse Analysis

Berkshire Hathaway Energy Montana’s newly commissioned Glacier Battery System marks a significant milestone in the region’s energy transition. The 75‑megawatt, 150‑megawatt‑hour battery storage facility, built at a cost of roughly $100 million near Cut Bank, provides rapid response capacity that can smooth fluctuations from wind and solar generation. By delivering instant power during peak demand or unexpected outages, the system enhances grid stability and reduces reliance on fossil‑fuel peaker plants. Its modular design also positions the asset for future expansion as Montana’s renewable mix continues to evolve.

The battery’s integration into the Western Energy Imbalance Market (WEIM) unlocks economic and operational advantages that extend far beyond Montana’s borders. WEIM links the California Independent System Operator’s real‑time market with twelve western states, allowing participants to buy and sell electricity where it is cheapest and most abundant. BHE Montana can now dispatch stored energy to offset deficits elsewhere, earning revenue while contributing to regional emissions reductions. Real‑time trading also improves overall system efficiency, smoothing price volatility and enabling higher penetrations of intermittent renewables across the interconnected grid.

Montana’s renewable portfolio, already dominated by hydropower and wind, is poised for diversification as BHE expands its solar footprint with the 130‑megawatt Glacier Solar Park under construction. The state’s early renewable portfolio standard and supportive loan programs have accelerated clean‑energy adoption, positioning it among the nation’s top ten states for renewable generation share. By coupling large‑scale wind farms with battery storage and forthcoming solar capacity, BHE creates a flexible, low‑carbon supply chain that can respond to market signals in WEIM. This integrated approach sets a template for other utilities seeking to balance reliability with decarbonization goals.

Berkshire Hathaway Energy Montana energises 150MWh BESS

By April Bonner · February 3, 2026

Warren Buffett’s Berkshire Hathaway‑owned BHE Montana has successfully energised its 75 MW/150 MWh 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.

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 ten largest generating plants by capacity and annual generation.

The state’s solar generation is relatively small by comparison, 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 189 MW Rim Rock wind farm near Kevin, Montana, along with the 105 MW Glacier I and 103.5 MW 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 130 MW solar project.