Due to awareness on the scarcity of fossil fuels and increased media coverage regarding global warming, alternatives such as Biofuels have gained an increased attention worldwide. However, researchers writing in the online edition of the May 7 Science magazine have now come to the conclusion that using ethanol to fuel our cars might not be the best idea after all.
Since growing energy crops are likely to compete with food crops for fertile ground, which would lead to the clearance of more forests to increase farmland, the researchers claim to have found a better alternative: convert biomass to electricity rather than ethanol.
Example of a “blogger” plant, where its bioelectrical signals are used to issue posts at a blog in Japan
By comparing both, the researchers have found that 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 global warming.
“It’s a relatively obvious question once you ask it, but nobody had really asked it before,” says study co-author Chris Field, director of the Department of Global Ecology at the Carnegie Institution. “The kinds of motivations that have driven people to think about developing ethanol as a vehicle fuel have been somewhat different from those that have been motivating people to think about battery electric vehicles, but the overlap is in the area of maximizing efficiency and minimizing adverse impacts on climate.”
Field, who is also a professor of biology at Stanford University and a senior fellow at Stanford’s Woods Institute for the Environment, is part of a research team that includes lead author Elliott Campbell of the University of California, Merced, and David Lobell of Stanford’s Program on Food Security and the Environment. The researchers performed a life-cycle analysis of both bioelectricity and ethanol technologies, taking into account not only the energy produced by each technology, but also the energy consumed in producing the vehicles and fuels. For the analysis, they used publicly available data on vehicle efficiencies from the US Environmental Protection Agency and other organizations.
While the results of the study clearly favor bioelectricity over ethanol, the researchers caution that the issues facing society in choosing an energy strategy are complex. “We found that converting biomass to electricity rather than ethanol makes the most sense for two policy-relevant issues: transportation and climate,” says Lobell. “But we also need to compare these options for other issues like water consumption, air pollution, and economic costs.”
“There is a big strategic decision our country and others are making: whether to encourage development of vehicles that run on ethanol or electricity,” says Campbell. “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.”
More details on the story can be found at the Carnegie Institution for Science