Energy Storage Systems (ESS, Inc.) was launched in 2011 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 validation, backed by ARPA-E and others, the company began shipping turn-key battery solutions in 2016.

The breakthrough 50kW/400kWh Iron Flow Battery (IFB) integrates a proprietary and patented all-iron electrolyte with low cost and non-toxic materials that enables us to offer one of the lowest installed cost/kWh storage systems on the market.

ESS Inc. envisions future limitations of Li-ion in the next frontier of flexible, long-duration storage and sees flow batteries, and especially the all-iron flow battery with its fast response time and limitless cycling, as being capable of making a future of energy storage capabilities a reality today.

ESS Inc. is poised to lead project developers, utility representatives, and EPC’s in the transition to a more flexible, longer-duration energy storage asset that can be used in many different use cases and for many different durations of time from 2-8 hours when responding to increased penetration of renewables. The IFB provides the flexibility to install a storage asset today that will be able to react to the emerging applications and use cases of the future.

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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. EVANSChief Executive Officer & Founder

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

DR. JULIA SONGChief Technology Officer & Founder

WILLIAM R SPROULL VP Business Development & Sales at Energy Storage Systems

WILLIAM R SPROULLVP Business Development & Sales

MARK HAGEDORN Director of Operations at Energy Storage Systems

MARK HAGEDORNDirector of Operations