The first Volt from GM was also a plug-in hybrid, but it was built in 1980

Green Car Reports

Electric Auto Corporation receives that distinction for their car built in 1980, at the height of America's second gas crisis. CHECK OUT: Modern electric cars. Chevrolet's Volt wasn't the original, or even the first Volt from GM. It built the Silver Volt, a plug-in hybrid based on a contemporary Buick station wagon—16 years before the GM EV1. Plug-In Hybrids

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