Could the California Air Resources Board (CARB) be taking a $55-million bite out of Tesla Motors' profits? The state regulator, which grants zero-emission vehicle (ZEV) credits for automakers making plug-in vehicles, is planning to reduce the number of credits generated by each Model S battery-electric sedan from seven to four, Bloomberg News reports. That means the California-based automaker will have fewer credits to sell to big buyers such as General Motors and Chrysler, who don't make enough ZEVs on their own to comply with state mandates.

While the selling price for these credits isn't disclosed (they're private transactions), the market was a lucrative one for Tesla, which generated $129.8 million in revenue from California zero-emissions credit sales and about another $65 million selling US Corporate Average Fuel Economy (CAFE) credits last year. All told, California and federal zero-emissions credit sales accounted for about 10 percent of Tesla's sales last year. A Tesla representative didn't immediately respond to a request from AutoblogGreen for comment.

This issue first came up last year when CARB hinted that it wouldn't give Tesla credit for having a battery-swapping option as it's method for quick-fueling compliance. Tesla, which appears to have been preparing for just this scenario, has been collecting revenue on credits since 2010 and achieved its first-ever profitable quarter in the first quarter of 2013 because of such credits.

While the maximum number of zero-emissions credits a vehicle could garner was increased from seven to nine in the new rules, Tesla can't take advantage of that because it meets neither of the most stringent criteria: that the car in question is rated to go more than 300 miles on a full tank or battery and be able to be "filled up" (or fully charged, in this case) within 15 minutes. Those are more hydrogen fuel-cell-like targets, but Tesla has the EVs that come closest to meeting them.
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