Assessing the Fuel Economy Potential of Light-Duty Vehicles

This paper assesses the potential for car and light truck fuel economy improvements by 2010-15. We examine a range of refinements to body systems and powertrain, reflecting current best practice as well as emerging technologies such as advanced engine and transmission, lightweight materials, integrated starter-generators, and hybrid drive. Engine options are restricted to those already known to meet upcoming California emissions standards. Our approach is to apply a state-of-art vehicle system simulation model to assess vehicle fuel economy gains and performance levels. We select a set of baseline vehicles representing five major classes - Small and Standard Cars, Pickup Trucks, SUVs and Minivans - and analyze design changes likely to be commercially viable within the coming decade. Results vary by vehicle type. A moderate package of conventional technology improvements yields fuel economy increases of 37% for a full-size pickup to 70% for a standard-performance midsize SUV, averaging 47% overall for a 5% increase in average vehicle price. Greater degrees of improvement are feasible at higher cost, with more than doubled fuel economy possible using full hybrid drive.