ESS Inc. is the first long-duration energy storage company to go public in the U.S. Since 2011, we have transformed the value proposition for long-duration storage through our unique iron flow battery technology. Transitioning from fossil fuels to renewable energy sources is more important than ever, and we believe our technology is a game changer in enabling the power grid of the future, today.

Differentiated Technology

ESS’ one-of-a-kind iron flow battery technology is the first to market, giving us a first mover advantage. The raw ingredients of iron, salt, and water are responsibly sourced, earth-abundant, and easy to recycle, making our low-cost technology the most environmentally sustainable option available today. Iron-flow technology also means our batteries are non-flammable, non-toxic, and carry no risk of explosion, making them flexible enough to deploy in a wide range of climates or geographies.

Longer Duration

Renewable intermittency creates issues for the electrical grid, which can require electricity when renewable sources are not generating and lacks sufficient energy storage capability to ensure reliability. ESS shifts supply to meet demand with long-duration energy storage systems that discharge energy for up to 12 hours, compared to lithium-ion batteries which typically offer a maximum duration of 4 hours. Our long-duration iron flow batteries improve grid stability, enhance the value of renewable energy, and enable greater resiliency to extreme weather and other unexpected events.