TL;DR
The batteries that keep the lights on after the sun sets are mostly built from lithium, a metal at the center of global supply fights. A GM-backed start-up says a different recipe, made with sodium, the abundant element in table salt, is about to come off an American factory line in real volume. Peak Energy's chief executive says its Sacramento plant opened in July and should turn out batteries able to hold "very close to a gigawatt-hour" of electricity in 2027 and more than that in 2028. The company also says its batteries need no heater in cold weather, where today's standard grid packs can freeze. If it holds up, power companies could get a second, homegrown way to store cheap solar and wind power for when people need it. Those figures are the company's own and have not been independently checked. Our odds that Peak Energy makes more than a gigawatt-hour of batteries in a year: 80%, likely by 2028. For the reasoning behind those odds and a timeline of the steps toward lithium-free grid storage, subscribe.
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