Looking forward, there is another possible hurdle for Tesla's profits. The California Air Resources Board (CARB) is thinking about changing the way it calculates zero-emission vehicle bonus credits. These would not be retroactive, but CARB may no longer allow battery swapping – which the Model S has – to get the bonus as a fast refueling option. This would reduce the value of Tesla's ZEV credits that it sells to other automakers. In the first quarter, Tesla made $11.2 million in profit and took in $67.9 million in revenue from selling ZEV and other "regulatory" credits. You can see how, if the ZEV value declines, the company's profit could also go away. Three months ago, Tesla said it was prepared for Q4 2013 ZEV credits to equal zero and yet Tesla CEO Elon Musk has said the company will be profitable by the end of the year even without selling credits.
Tesla has long relied on ZEV credits, and all the way back in 2010 there were stories about how the credits were running out so this is well-trodden ground. You can find all of the details of Tesla's 2013 Q1 profits here and read more about the potential CARB changes here.