A new study of the carbon dioxide emissions, cropland area requirements, and other environmental consequences of growing corn and sugarcane to produce fuel ethanol indicates that the "direct and indirect environmental impacts of growing, harvesting, and converting biomass to ethanol far exceed any value in developing this energy resource on a large scale." The study, published in the July 2005 issue of BioScience, the journal of the American Institute of Biological Sciences (AIBS), uses the “ecological footprint” concept to assess needs for ethanol production from sugarcane, now widespread in Brazil, and from corn, which is increasing in the United States.
In Brazil, ethanol from fermentation of sugarcane is used pure or blended with gasoline to yield gasohol, which contains 24 percent ethanol. In the United States, ethanol made from corn, production of which is heavily subsidized, is used in an 85 percent ethanol mixture called E85. In 2003, ethanol-blended gasoline accounted for more than 10 percent of gasoline sales in the United States.
The authors of the study assessed the energy required to produce the crops and to manufacture and distribute the resulting fuels. In the United States, ethanol yielded only about 10 percent more energy than was required to produce it; in Brazil, where a different process is used, ethanol yielded 3.7 times more energy than was used to produce it. The researchers, Marcelo E. Dias de Oliveira, Burton E. Vaughan, and Edward J. Rykiel, Jr., also weighed effects of fuel ethanol use on carbon dioxide emissions, soil erosion, loss of biodiversity, and water and air pollution, assuming vehicles representative of each country. Specialized software was used to analyze the sensitivity of the conclusions to diverse assumptions in the analysis.
Donna Royston | EurekAlert!
A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes
20.07.2018 | Science China Press
Future electronic components to be printed like newspapers
20.07.2018 | Purdue University
A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.
The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
20.07.2018 | Power and Electrical Engineering
20.07.2018 | Information Technology
20.07.2018 | Materials Sciences