Researchers identify energy gains and environmental impacts of corn ethanol and soybean biodieselJuly 12, 2006The first comprehensive analysis of the full life cycles of soybean biodiesel and corn grain ethanol shows that biodiesel has much less of an impact on the environment and a much higher net energy benefit than corn ethanol, but that neither can do much to meet U.S. energy demand. The study will be published in the July 11 Proceedings of the National Academy of Sciences. The researchers tracked all the energy used for growing corn and soybeans and converting the crops into biofuels. They also looked at how much fertilizer and pesticide corn and soybeans required and how much greenhouse gases and nitrogen, phosphorus, and pesticide pollutants each released into the environment.
"Quantifying the benefits and costs of biofuels throughout their life cycles allows us not only to make sound choices today but also to identify better biofuels for the future," said Jason Hill, a postdoctoral researcher in the department of ecology, evolution, and behavior and the department of applied economics and lead author of the study. The study showed that both corn grain ethanol and soybean biodiesel produce more energy than is needed to grow the crops and convert them into biofuels. This finding refutes other studies claiming that these biofuels require more energy to produce than they provide. The amount of energy each returns differs greatly, however. Soybean biodiesel returns 93 percent more energy than is used to produce it, while corn grain ethanol currently provides only 25 percent more energy. Still, the researchers caution that neither biofuel can come close to meeting the growing demand for alternatives to petroleum. Dedicating all current U.S. corn and soybean production to biofuels would meet only 12 percent of gasoline demand and 6 percent of diesel demand. Meanwhile, global population growth and increasingly affluent societies will increase demand for corn and soybeans for food. The authors showed that the environmental impacts of the two biofuels also differ. Soybean biodiesel produces 41 percent less greenhouse gas emissions than diesel fuel whereas corn grain ethanol produces 12 percent less greenhouse gas emissions than gasoline. Soybeans have another environmental advantage over corn because they require much less nitrogen fertilizer and pesticides, which get into groundwater, streams, rivers and oceans. These agricultural chemicals pollute drinking water, and nitrogen decreases biodiversity in global ecosystems. Nitrogen fertilizer, mainly from corn, causes the 'dead zone' in the Gulf of Mexico. "We did this study to learn from ethanol and biodiesel," says David Tilman, Regents Professor of Ecology and a co-author of the study. "Producing biofuel for transportation is a fledgling industry. Corn ethanol and soybean biodiesel are successful first generation biofuels. The next step is a biofuel crop that requires low chemical and energy inputs and can give us much greater energy and environmental returns. Prairie grasses have great potential." Biofuels such as switchgrass, mixed prairie grasses and woody plants produced on marginally productive agricultural land or biofuels produced from agricultural or forestry waste have the potential to provide much larger biofuel supplies with greater environmental benefits than corn ethanol and soybean biodiesel. According to Douglas Tiffany, research fellow, department of applied economics and another co-author of the study, ethanol and biodiesel plants are early biorefineries that in the future will be capable of using different kinds of biomass and conversion technologies to produce a variety of biofuels and other products, depending upon market demands. Hill adds that both ethanol and biodiesel have a long-term value as additives because they oxygenate fossil fuels, which allows them to burn cleaner. Biodiesel also protects engine parts when blended with diesel. "There is plenty of demand for ethanol as an additive," Hill says. "The ethanol industry was built on using ethanol as an additive rather than a fuel. Using it as a biofuel such as E85 is a recent and currently unsustainable development. As is, there is barely enough corn grown to meet demand for ethanol as a 10 percent additive." University of Minnesota | |||||||||||||||||||||
|
Related Biodiesel Current Events and Biodiesel News Articles Simple device which uses electrical field could boost gas efficiency With the high cost of gasoline and diesel fuel impacting costs for automobiles, trucks, buses and the overall economy, a Temple University physics professor has developed a simple device which could dramatically improve fuel efficiency as much as 20 percent. Iowa State engineer works to clean and improve engine performance The five engines in Song-Charng Kong's Iowa State University laboratory have come a long way since Karl Benz patented a two-stroke internal combustion engine in 1879. MSU's discovery of plant protein holds promise for biofuel production Scientists at Michigan State University have identified a new protein necessary for chloroplast development. The discovery could ultimately lead to plant varieties tailored specifically for biofuel production. Turning Waste Material into Ethanol Say the word "biofuels" and most people think of grain ethanol and biodiesel. But there's another, older technology called gasification that's getting a new look from researchers at the U.S. Department of Energy's Ames Laboratory and Iowa State University. By combining gasification with high-tech nanoscale porous catalysts, they hope to create ethanol from a wide range of biomass, including distiller's grain left over from ethanol production, corn stover from the field, grass, wood pulp, animal waste, and garbage. Are microbes the answer to the energy crisis? The answer to the looming fuel crisis in the 21st century may be found by thinking small, microscopic in fact. Microscopic organisms from bacteria and cyanobacteria, to fungi to microalgae, are biological factories that are proving to efficient sources of inexpensive, environmentally friendly biofuels that can serve as alternatives to oil, according to research presented at the 108th General Meeting of the American Society for Microbiology in Boston. New source for biofuels discovered A newly created microbe produces cellulose that can be turned into ethanol and other biofuels, report scientists from The University of Texas at Austin who say the microbe could provide a significant portion of the nation's transportation fuel if production can be scaled up. Money Doesn't Grow on Trees, But Gasoline Might Researchers have made a breakthrough in the development of "green gasoline," a liquid identical to standard gasoline yet created from sustainable biomass sources like switchgrass and poplar trees. New Research Suggests Biofuel Blending is Often Inaccurate While sampling blended biodiesel fuels purchased from small-scale retailers, researchers at the Woods Hole Oceanographic Institution found that many of the blends do not contain the advertised amount of biofuel. International effort takes critical steps to accelerate growth of global biofuels market The governments of the United States, Brazil and the European Union (EU)-the world's major producers of biofuels-today released an analysis of current biofuel specifications with the goal of facilitating expanded trade of these renewable energy sources. Growing markets bring potential for rubber and oilseed crops Changing and growing markets have renewed interest and research on guayule and lesquerella, two native Big Bend plants that might be grown in other parts of Texas, a Texas AgriLife Research scientist said. More Biodiesel Current Events and Biodiesel News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||