Jacobson vehicle fleet analysis

[Lance Christie]

Mark Jacobson, professor of civil and environmental engineering at Stanford University and director of Stanford’s Atmosphere/Energy Program, assessed energy sources in terms of their impacts on global warming, human health, energy security, water supply, space requirements, wildlife, water pollution, reliability and sustainability.  The paper with his findings will be published in the January, 2009, Energy and Environmental Science; I obtained it online in December 2008.  Jacobsen then assessed vehicular transportation alternatives from best to worst against the same criteria by assuming that the entire U.S. vehicular fleet was powered by each energy source in turn, utilized in battery electric vehicles, hydrogen fuel cell vehicles, or “flex-fuel” internal combustion vehicles than can run either on petroleum or ethanol E85 fuel.

By Jacobson’s calculations, the best to worst vehicle options are:
        1.  Battery electric vehicles charged from wind-generated electric power
        2.  Hydrogen fuel cell vehicles fueled from wind-generated hydrogen
        3.  Battery electric vehicles charged from concentrating solar power plants
        4.  Battery electric vehicles charged from geothermal power plants
        5.  Battery electric vehicles charged from tidal power plants
        6.  Battery electric vehicles charged from solar photovoltaic panels
        7.  Battery electric vehicles charged from wave power plants
        8.  Battery electric vehicles charged from hydroelectric power plants

9.  A tie between battery electric vehicles charged from nuclear or sequestered-carbon coal-fired power plants.

11.  Flex-fuel vehicles burning E85 ethanol blend derived from corn

12.  Flex-fuel vehicles burning E85 ethanol derived from cellulostic farmed source like switchgrass.

Jacobson found that battery electric vehicles require one third the energy to travel a mile as do hydrogen fuel cell vehicles, when all energy consumed in producing, delivering, and utilizing the traction energy is totaled.

Jacobson notes that hydrogen fuel cell vehicles can be refueled rapidly while battery electric vehicles cannot, and battery electric vehicles have limited range on each charge.  He recommends a battery/fuel cell electric hybrid vehicle be developed which could run on battery charge for commuting and shopping, but utilize hydrogen fuel for long trip power.  He sees hydrogen fuel cell vehicles being useful for trips of over 250 miles, while battery electric vehicles could be used for local commuting.