Eos Energy delivers 3 MW/15MWh zinc battery for California tribal land project

A second project between zinc hybrid cathode battery storage maker Eos Energy Enterprises and project developer Faraday Microgrids has been announced. 

The new order confirms the deployment of a zinc-based battery energy storage system on tribal land in California, though the location was not announced. The 3 MW/15 MWh Eos Z3 system, which uses an aqueous zinc-bromine chemistry, will support a renewable microgrid designed to enhance resilience for the undisclosed tribe’s facilities, supplying backup power, and providing demand savings.

Partially funded by the California Energy Commission (CEC), the project aims to integrate long-duration energy storage technology into tribal infrastructure. It also reinforces Eos Energy’s commitment to expand its presence in California’s growing energy storage market.

Eos Energy chief commercial officer and interim chief financial officer, Nathan Kroeker, emphasized the significance of the deployment. 

“As a repeat order through our established partners at Faraday and the CEC, this deployment serves as a testament to the strength of our commercial relationships and reinforces our mission to deliver resilient, reliable and domestically manufactured energy solutions,” Kroeker said. 

Faraday Microgrids chief executive officer David Bliss stated the collaboration will support a Native American community.

“It is our great pleasure to once again partner with Eos to deploy their cutting-edge zinc-bromide energy storage technology in one of the largest renewable energy microgrids in the Western United States,” Bliss said.

“This will support a Native American community and contribute to bulk grid-edge power stability and availability…demonstrating the ability of distributed energy resources to support the safety and growth of vibrant communities in California and across North America.”

Eos Energy also announced new debt funding. The publicly listed company said it raised $225 million through an upsized convertible notes offering due 2030, with proceeds to refinance existing debt and support general operations. The notes carry a 6.75% interest rate and are convertible at a premium. The company said proceeds will go toward repurchasing $126 million in existing notes, prepaying $50 million in debt, and general corporate use. Overall, the move reduces near-term debt pressure while giving Eos more time to scale its zinc battery tech.

Previously, the company secured a $315.5 million investment from an affiliate of Cerberus Capital Management to expand its long-duration energy storage market footprint. Eos Energy manufactures its batteries in East Pittsburgh, Pennsylvania, after a stint manufacturing in China.

In mid 2024, the company said it was aiming for 8 GWh of annual energy storage production capacity in the U.S. by 2026 as part of its $500 million program called AMAZE (American Made Zinc Energy) backed by the U.S. Department of Energy. 

The tribal land project will be Eos Energy’s eighth project with the CEC, who recently stated that California had reached 15,763 MW of battery capacity as of April 2025.