Ameresco Powers Arizona’s Energy Future with Largest Behind-the-Meter Battery Storage for Nucor Expansion
Ameresco, a leading energy solutions provider committed to accelerating the clean energy transition, has announced the development and commercial operation of a 50MW/200 MWh battery energy storage system (BESS) — the largest behind-the-meter (BTM) project in Arizona. Achieving commercial operation in October 2025, this milestone represents a significant advancement for the state’s energy infrastructure and a critical step forward in supporting industrial energy resilience.
The BESS, located in Kingman, Arizona, was developed for Nucor, the largest steel producer in North America. Nucor is undergoing a major expansion at its Kingman bar mill, which includes the installation of a new electric arc furnace. This expansion will increase the facility’s annual production capacity to 600,000 tons, strengthening Nucor’s operational capabilities and reinforcing the site’s role as a cornerstone of steel manufacturing in the region.
Construction of the battery system began in December 2024 and featured the deployment of 58 Tesla Megapack 2XL units. The system operates under a 20-year Storage Services Agreement (SSA) and is owned by Ameresco. 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 — the BESS is strategically positioned to enhance grid stability while supporting Nucor’s expanded energy needs.
In addition to the battery project, Ameresco will deliver a 25 MW AC solar asset scheduled for operation in 2026. This complementary solar installation will further strengthen Nucor’s energy transition efforts, providing clean, reliable power to support the expanded operations at Kingman.
“Being selected for this groundbreaking BESS project is a tremendous honor,” said Jonathan Mancini, Senior Vice President of Solar & BESS Project Development at Ameresco. “By deploying a battery energy storage system onsite at Nucor’s Kingman plant, we are helping to support their growth while creating a more resilient, reliable, and sustainable energy future.”
The onsite battery system will play a critical role in stabilizing the electric load generated by Nucor’s new arc furnace. Large industrial processes like steel production can cause significant fluctuations in energy demand, putting strain on local grids. The BESS smooths these fluctuations, reducing stress on the grid and enabling more efficient energy management by utilities. This capability also facilitates increased utilization of renewable energy, aligning with broader climate goals.
“The battery energy storage system at our Kingman mill is a site-specific solution designed to address the unique demands of our operations,” said Matt Blitch, Vice President & General Manager at Nucor. “We are grateful for the collaboration with Ameresco and our utility partners in delivering a system that not only supports our expansion but also ensures operational reliability and efficiency.”
The project exemplifies the growing trend of behind-the-meter energy storage solutions for industrial operations. By placing storage directly onsite, companies like Nucor can better manage their energy use, reduce costs, and enhance reliability while supporting grid stability. Ameresco’s BESS system is designed to respond dynamically to the mill’s energy demands, storing excess energy when consumption is low and discharging during peak demand periods, optimizing both operational efficiency and energy sustainability.
GreenFront Energy Partners played a key advisory role in structuring and contracting the solar and storage solutions at Kingman, ensuring that Nucor’s energy strategy is both cost-effective and aligned with long-term sustainability goals. Their expertise helped facilitate a solution that integrates battery storage and solar energy seamlessly into the facility’s operations.
Beyond operational benefits, the project represents a broader commitment to the energy transition in the industrial sector. By deploying advanced battery storage and solar solutions, Ameresco and Nucor are demonstrating how heavy industry can leverage clean energy technologies to reduce environmental impact while maintaining high productivity levels. This initiative highlights the importance of innovation and collaboration between energy developers, utilities, and industrial operators.
The Kingman BESS project also sets a benchmark for similar industrial-scale energy storage projects in the region and across the U.S. As more industries look to electrify operations and integrate renewable energy, behind-the-meter storage is emerging as a vital tool to enhance energy resilience, reduce carbon footprints, and support grid stability.
“This project underscores the transformative potential of energy storage in industrial settings,” Mancini added. “We are proud to deliver a system that not only meets Nucor’s immediate energy needs but also contributes to a cleaner, more resilient energy future for Arizona and the nation.”
With the Kingman BESS now operational and the solar asset on the horizon, Nucor is well-positioned to meet its expansion goals while advancing its sustainability and energy efficiency objectives. The collaboration between Ameresco, Nucor, AEPCO, and GreenFront Energy Partners serves as a model for industrial energy transition projects nationwide, demonstrating that reliability, resilience, and sustainability can be achieved simultaneously.
