Will Energy Storage Play a Big Role in the Electric Grid?

More than 200 tops spin in vessels half-buried in the dirt outside Stephentown, N.Y., a town near the Massachusetts state line. Inside the vessel a vacuum permits each top to rotate as many as 16,000 times per minute, despite the fact that each weighs more than one metric ton, thanks to its steel and carbon-fiber composition

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Will Energy Storage Play a Big Role in the Electric Grid?