Established in 2011, ESS Inc. manufactures low-cost, long-duration all-iron redox flow batteries for commercial and utility-scale energy storage applications requiring 4+ hours of flexible energy capacity. Its product, Energy Warehouse™, uses iron, salt, and water for the electrolyte, and delivers an environmentally safe, long-life energy storage solution for the world’s renewable energy infrastructure.

Based in Wilsonville, Oregon, ESS Inc. was founded by a team with deep experience in fuel cells, electrochemistry, advanced material science and renewable energy. After five years of intensive innovation, engineering development and rigorous testing and validation, with the backing of ARPA-E and others, the company began shipping turnkey energy storage solutions in 2015.

In 2017, BASF, the world’s leading chemical company, became a significant investor in ESS Inc., joining forces to deliver energy storage solutions for a sustainable future.

Today’s choices for commercial battery technologies include highly competitive alternative chemistries, such as flow batteries. The limitations of lithium-ion batteries – cycle life, safety, disposability – will become more of an issue as the need for more flexible, longer-duration storage increases. With its safe, proven and earth-abundant all-iron flow battery, ESS is helping project developers, utilities, and EPCs make the transition to more flexible non-lithium-ion storage that is better suited for the grid in a variety of applications.

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The ESS management team consists of seasoned veterans with decades of experience in cleantech, distributed power generation, and energy storage technologies. We understand how the economics of renewables is evolving and how the grid has to change to accommodate deeper penetrations. We are motivated to enable this transition with cost effective, reliable, and flexible energy storage solutions that match the project lives of wind and solar.

CRAIG E. EVANS Chief Executive Officer & Founder of Energy Storage Systems

CRAIG E. EVANS Chief Executive Officer & Founder

DR. JULIA SONG Chief Technology Officer & Founder at Energy Storage Systems

DR. JULIA SONG Chief Technology Officer & Founder

JAY CORN Chief Financial Officer

JAY CORN Chief Financial Officer

HUGH MCDERMOTT VP Business Development & Sales at Energy Storage Systems

HUGH MCDERMOTT Senior VP Business Development & Sales

SHELLEY PENG VP Marketing and Communications

MARK HAGEDORN Director of Operations at Energy Storage Systems

MARK HAGEDORN Director of Operations