According to General Motors E-Flex spokesman Rob Peterson, the automaker has reached an agreement with the California Air Resources Board (CARB) that would see the 2011 Chevy Volt get a unique classification different from other current hybrids. This new classification takes into account the fact that the Volt's 40-mile battery range allows it to complete the bulk of the emissions and economy test procedure without ever running the engine, which would likely give it a mpg rating of 100 mpg or better.
This is problematic for the EPA, which considers dual-power vehicles like the series hybrid Volt no different than a parallel hybrid like the Prius. Currently the EPA is expecting the Volt to complete the test cycle with a charged battery, which means the engine would have to run a lot more and essentially kill the charge sustaining control plan. According to Peterson, GM is still a long way from reaching an agreement with the feds on how to test the Volt, despite what the Detroit Free Press says. However, having CARB consider the Volt essentially an electric car is certainly a bargaining chip in GM's favor.