Transitions to Alternative Vehicles and Fuels (NAS, 2013)
This National Research Council (NRC) report assesses the potential to achieve twin goals of reducing petroleum use and cutting greenhouse gas (GHG) emissions from U.S. cars and light trucks to 80 percent below the 2005 level by 2050. The product of a two-and-a-half year effort, the study was conducted by a committee of experts in vehicle and fuel technologies, including U-M Energy Institute research professor John DeCicco and 17 other members from academia, consultancies, environmental organizations and other research institutions.
The resulting report examines the current status, projected future capabilities, costs and barriers to key technologies for improving fuel economy and deploying alternative fuels and vehicles (AFVs). In addition to advances in gasoline vehicles using internal combustion engines as well as plugless hybrid drive, the AFV options evaluated include biofuels, compressed natural gas, plug-in hybrids, battery electric vehicles and hydrogen fuel cell vehicles. Although reaching the 2050 goals would be difficult, the committee concluded that the targets could be met or closely approached using various combinations of technology as long as strong policies are put in place to overcome high costs and influence consumer choices.
Vehicles must become dramatically more fuel efficient regardless of what fuel is used to power them. The committee also found that alternative (non-petroleum) fuels must become readily available, cost-effective and produced with very low GHG emissions. Given the many uncertainties and barriers, no clear winner emerged among the AFV options evaluated, and any transition to AFVs will be costly and require several decades. Nevertheless, the committee's model calculations, while exploratory and highly uncertain, indicate that the benefits of making the transition would exceed its added costs. These benefits are savings in consumer energy expenditures, reductions in petroleum use and reductions in GHG emissions.
The policies needed to achieve the petroleum and GHG reduction goals include ongoing increases in light vehicle fuel economy and GHG standards (to levels more stringent than those already promulgated through 2025) as well as other strong and sustained but adaptive policies such as other regulations, subsidies, energy taxes, research and development (R&D) and public information programs. Complementary policies to reduce GHG emissions in the energy sectors that supply fuels to cars and light trucks are also necessary for achieving the GHG reduction goal.