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Jorge Cruz has just finished his overnight shift stacking shelves at Whole Foods in Los Altos, California, and is waiting at the bus stop outside. Like much of Silicon Valley, there's a regular flow of Tesla, BMW, Nissan and Google electric cars that cruise past from their nearby headquarters, and Cruz rather likes them.

"I really wouldn't mind having an electric car," he says, though his first choice is probably a Honda or an Acura. Regardless, for now, he rides the bus. "I need to save up for a car," he explains.