Engineering-economic analyses of automotive fuel economy potential in the United States

Over the past 25 years more than 20 major studies have examined the technol ogical potential to improve the fuel economy of passenger cars and light tr ucks in the United States. The majority have used technology/cost analysis, a combination of analytical methods from the disciplines of economics and automotive engineering. In this review we describe the key elements of this methodology, discuss critical issues responsible for the often widely dive rgent estimates produced by different studies, review the history of this m ethodology's use, and present results from six recent assessments. Whereas early studies tended to confine their scope to the potential of proven tech nology over a 10-year time period, more recent studies have focused on adva nced technologies, raising questions about how best to include the likeliho od of technological change. The review concludes with recommendations for f urther research.