(97f) Transitions to Alternative Transportation Technologies; A Focus On Hydrogen

In response to a congressional request in the Energy Policy Act of 2005, this National Research Council (NRC) study estimated the maximum practicable number of hydrogen fuel cell vehicles (HFCVs) that could be deployed in the United States by 2020 and beyond, together with the investments, time, and government actions needed to carry out this transition. The study determined the consequent reductions in U.S. oil consumption and emissions of carbon dioxide (CO2)?the main greenhouse gas linked to global climate change?that could be expected. It then compared those reductions with the potential impact that the use of alternative vehicle technologies and biofuels might have on oil consumption and CO2 emissions.

The NRC's Committee concluded that the maximum practical number of HFCVs that could be operating in 2020 would be approximately 2 million in a fleet of 280 million light-duty vehicles. The number of HFCVs could grow rapidly thereafter to about 25 million by 2030.By 2050 HFCVs could account for more than 80 percent of new vehicles entering the fleet.

The use of HFCVs can achieve large and sustained reductions in U.S. oil consumption and CO2 emissions, but several decades will be needed to realize these potential long-term benefits. Considerable progress is still required toward improving fuel cell costs and durability, as well as on-board hydrogen storage.

The committee also found that alternatives such as improved fuel economy for conventional vehicles, increased penetration of hybrid vehicles, and biomass-derived fuels could deliver significantly greater reductions in U.S. oil use and CO2 emissions than could use of HFCVs over the next two decades, but that the longer-term benefits of such approaches were likely to grow at a smaller rate thereafter, even with continued technological improvements, whereas hydrogen offers greater longer-term potential. Thus, as estimated by the committee, the greatest benefits will come from a portfolio of R&D technologies that would allow the United States to achieve deep reductions in oil use, nearly 100 percent by 2050 for the light-duty vehicle fleet. Achieving this goal, however, will require significant new energy security and environmental policy actions in addition to technological developments.