Factor of two : halving the fuel consumption of new U.S. Automobiles by 2035

The chapter describes how the United States (U.S.) transport sector is almost totally dependent on gasoline and diesel fuel refined from oil to provide the remarkable mobility provided by the automobile. This dependence presents a challenging energy and environmental problem, as the transportation sector is responsible for two-thirds of total petroleum consumption and a third of the nation’s carbon emissions. Amid growing concerns over energy security, and the impacts of global climate change, the U.S. Congress in December 2007 adopted a new legislative directive to increase the fuel economy of new passenger vehicles over the next two decades. Transportation experts at the Laboratory for Energy and Environment, part of the Massachusetts Instute of Technology (MIT) in Cambridge, Massachusetts, have examined the vehicle design and sales mix changes necessary to double the average fuel economy or halve the fuel consumption of new light duty vehicles (LDVs)—including cars, station wagons, sport utility vehicles (SUVs), pickup trucks and vans—by model year 2035. In order to achieve this factor of two target, three technology options that are available and can be implemented on a large scale were evaluated: (1) channeling future vehicle technical efficiency improvements to reducing fuel consumption rather than improving vehicle performance; (2) increasing the market share of diesel, turbocharged gasoline and hybrid electric gasoline propulsion systems; and (3) reducing vehicle size and weight.