The EPA gave the Volt a 93MPG rating. I like most people were very interested on how they got that magic number. So they have come up with a video that clears things up for us.
The hybrid electric Chevy Volt, which was released in the U.S. last week, presents a particularly unique challenge to rate because GM developed an extended-range hybrid drive train that essentially allows the car to run on electricity alone for its first 35 miles after which a gas-engine kicks in full time. The Volt’s complex system uses the car’s gas engine mostly as a generator to power the car’s electric drive train, but it also drives power directly to the wheels when going over 70 miles per hour.
If a driver recharges a Volt’s battery every 35 miles and runs the car on electricity alone, the Volt gets 93 MPGe. On gas alone, the car gets 37 MPGe. But the EPA also combines ratings for real-life use depending on how often the driver recharges the battery.