Code of Federal Regulations Title 10. Energy § 10.611.3 Advanced technology vehicle

(1) A combined average fuel economy calculation required under this paragraph for a vehicle that is a dual fueled automobile for the purpose of CAFE is calculated as if the vehicle were not a dual fueled automobile.

(2) The average combined fuel economy for vehicles with substantially similar attributes is a harmonic production weighted average of the combined average fuel economy of all vehicles with substantially similar attributes in model year 2005, as published by DOE.

(3) In the case of an electric drive vehicle with the ability to recharge from an off-board source, an automobile manufacturer must provide DOE with a test procedure and sufficient data to demonstrate that the vehicle meets or exceeds the applicable average combined fuel economy of vehicles with substantially similar attributes.