Bioelectricity is more efficient than ethanol
25 May, 2009 10:20 am
According to a study published in the online edition of the May 7 Science magazine, the best option to maximize our "miles per acre" from biomass is to convert the biomass to electricity, rather than ethanol. Lead author, Dr Elliott Campbell of the University of California, answers Scitizen's questions.
|Panicum virgatum L. switchgrass|
The electricity option is difficult to beat because the efficiency of the electric vehicle is much greater than the internal combustion engine vehicle.
Bioelectricity used for battery-powered vehicles would deliver an average of 80% more miles of transportation per acre of crops, while also providing double the greenhouse gas offsets to mitigate climate change, relative to a similar-sized gasoline-powered car.
Would you say that bioelectricity is with no doubt the energy of the future?
The internal combustion engine just isn't very efficient, especially when compared to electric vehicles. The transportation future will likely be a mix of renewable technologies rather than the current focus on liquid fuels.
You take into account neither water consumption nor atmospheric pollution or battery recycling. According to you, may these factors have an impact on the conclusions of the study?
The results of our study show that transportation and greenhouse gases reduction goals can be better met with electricity than ethanol. We don't make a conclusion about which energy pathway is best because there are other criteria that need to be evaluated such as economic costs and air pollution.
The current general tendency seems more favorable to ethanol. Do you have confidence in the capacity of countries to reverse their strategy as regards energy?
While the current focus on biofuels is liquid fuels there is an emerging awareness that conversion to electricity can be more efficient.
There is a big strategic decision our country and others are making: whether to encourage development of vehicles that run on ethanol or electricity. Studies like ours could be used to ensure that the alternative energy pathways we chose will provide the most transportation energy and the least climate change impacts.
Source: Greater Transportation Energy and GHG Offsets from Bioelectricity Than Ethanol, J. E. Campbell, D. B. Lobell, and C. B. Field. Originally published in Science Express on 7 May 2009. Science 22 May 2009: Vol. 324. no. 5930, pp. 1055 - 1057 DOI: 10.1126/science.1168885
Elliott Campbell works in the area of environmental science and engineering focused on sustainability science. His current research falls in the emerging interdisciplinary domain of sustainable biofuels design and focuses on the interaction of ecological and human energy systems.