World’s Largest Battery Made of Bricks Turns On in California

A Bay Area startup has turned on the world’s largest industrial heat battery.

Rondo Energy is helping power Holmes Western Oil Corp.’s enhanced oil recovery system. Holmes replaced one of its natural gas-fired boilers at a project in Kern County, California, with a 20-megawatt solar array paired with Rondo’s 100-megawatt-hour battery, which heats up clay bricks with electricity to generate steam that’s then used to force oil from the ground.

Critics argue that deploying clean tech to produce fossil fuels prolongs the life of carbon-emitting infrastructure. Rondo investor Andy Lubershane, a partner at Energy Impact Partners, views it differently.

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