Tesla Motors has earned more than $295 million in green subsidy emission credits during the past three years for a battery-swapping technology customers weren’t getting, a Watchdog investigation reveals.

In fact, the electric car company, owned in part by billionaire Elon Musk, may have earned credits up to nearly half a billion dollars in value from the 11 states that use the Zero Emission Vehicle barter as part of a green auto industry mandate. California created the program and leads the pack, doling out $173 million in credits to the Silicon Valley-based Tesla.

Tesla claimed the credits between 2012 and mid-2014 — part of a program designed to encourage the carmaker to promote its new battery-swap technology. The program did not require evidence the company actually provided the service.

“What they were getting (the credits) for was the demonstration that they had a workable technology. And they do,” said Dave Clegern, spokesman for the California Air Resources Board. “It was demonstrated (by Telsa). They had it at a Tesla facility in California; we went there and saw it.”

That demonstration was in 2012, the same year Tesla started selling its Model S sedan. For each car Telsa sold, it received four ZEV credits plus an additional three credits for being part of a rapid refueling program. Each credit is worth about $4,000, Watchdog found.

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