In the scramble to develop more environmentally friendly transportation methods, a wide range of questions must be answered, including how automobiles may best be powered. Biomass might be an important source for that power, either to generate electricity for electric vehicles, or to make ethanol for combustion vehicles. Campbell et al. (p. 1055; published online 7 May; see the Policy Forum by Ohlrogge et al.) examined each approach's demands on land-use, using a life-cycle assessment model, for a range of energy feedstocks, conversion methods, and vehicle types. In nearly all cases, bioelectricity would have a significantly higher net transportation efficiency per area of land used than bioethanol, owing to the greater efficiency of electric engines. Furthermore, bioelectricity would result in a smaller CO_2 burden. Thus, bioelectricity could represent an important bridge to more advanced transportation technologies with less environmental impact.
展开▼
