Ameresco recently announced the development and commercial operation of a 50-MW/200 MWh battery energy storage system (BESS), the largest behind-the-meter (BTM) project in Arizona.
"Achieving commercial operation in October 2025, this milestone marks a significant advancement in the state’s energy infrastructure," it said.
The BESS was developed in Kingman, Arizona for Nucor, the largest steel producer in North America. Nucor’s bar mill is undergoing a major expansion that includes the installation of a new electric arc furnace. This expansion will help boost the facility’s production capacity to 600,000 tons annually, strengthening Nucor’s operational capabilities at the site.
Construction began in December 2024, featuring 58 Tesla Megapack 2XL units under a 20-year Storage Services Agreement (SSA).
The Ameresco-owned battery system was installed at a Nucor substation within Mohave Electric Cooperative’s territory and operated by Arizona Electric Power Cooperative (AEPCO), part of the Arizona G&T Cooperatives.
Ameresco will deliver a 25 MW AC solar asset, scheduled to begin operation in 2026, further supporting Nucor’s energy transition and site expansion.
Ameresco’s onsite battery Asset will help stabilize the electric load from Nucor’s new arc furnace, reducing strain on the grid. By smoothing energy demand, it makes it easier for the utility to manage power fluctuations and boosts the use of renewable energy, Ameresco said.
GreenFront Energy Partners advised Nucor on the contracting and structuring of solar and storage solutions at Kingman.
