How Yellowstone's renewable energy program ended up running on old car batteries

Solar power at Yellowstone's Lamar Buffalo Ranch field campus is stored in used hybrid batteries recovered from Toyota dealers. Here's how it happened

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When the first Prius hit the road in 1997, it was considered niche. As of the end of last year, Toyota has sold more than 2m Prius hybrids, more than half of a total of 3.5m hybrid cars of all models in the US alone. Together, they are taking a big bite out of gasoline consumption and emissions: hybrids use about 50% less gas and generate half as many emissions as traditional cars.