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Leading biofuels wreak environmental havoc mongabay.com January 3, 2008 Leading biofuels may be worse for environment than fossils fuels
Analyzing recent findings from a Swiss government study on 26 types of transport biofuels, Jorn P. W. Scharlemann and William F. Laurance say that arguments in favor of some large-scale biofuels often fail to fully account for the environmental costs of production, including destruction of forests, emissions of trace greenhouse gases, and air pollution. Fuels derived from "residual products, such as biowaste or recycled cooking oil, as well as ethanol from grass or wood" may offer lower environmental costs, according to the authors.
"The key point is that biofuels vary enormously in their relative merits. New biofuel technologies, especially those that focus on using fast-growing weedy plants or algae, are likely to be much more beneficial than using food crops for biofuels," he continued. "Food crops require lots of water, fertilizer, pesticides, and prime agricultural land, and these should be used for food--not biofuels." CITATION: J.P.W. Scharlemann and W.F. Laurance (2007). "How Green are Biofuels?" SCIENCE VOL 319 4 JANUARY 2008 Comments Related Biodiesel demand could destroy world's forests. Growing demand for biodiesel could drive large-scale forest conversion for energy crops, warns a study published in Conservation Biology. With petroleum supplies expected to peak in the next 5-30 years and growing concern over climate change, biodiesel production may expand by 100-fold by 2050, estimates Lian Pin Koh, a researcher from Princeton University. Koh says that much of this expansion could come at the expense of forests, but the degree of which depends on the feedstocks used. Energy crops like palm oil are significantly more productive than more widely used rapeseed -- which currently accounts for 84 percent of biodiesel production -- but are more likely to be established in carbon-rich and biodiverse ecosystems like the tropical forests of southeast Asia. As such, the environmental trade-off between feedstocks is complex. U.S. corn subsidies drive Amazon destruction. U.S. corn subsidies for ethanol production are contributing to deforestation of the Amazon rainforest, reports a tropical forest scientist writing in this week's issue of the journal Science. Dr. William Laurance, of the Smithsonian Tropical Research Institute in Panama, says that a recent spike in Amazonian forest fires may be linked to U.S. subsidies that promote American corn production for ethanol over soy production. The shift from soy to corn has led to a near doubling in soy prices during the past 14 months. High prices are, in turn, driving conversion of rainforest and savanna in Brazil for soy expansion. Does palm oil alleviate rural poverty in Malaysia?. While it is often argued that the economic benefits of oil palm plantations outweigh the environmental costs of converting biodiverse ecosystems to monocultures, new analysis suggests that the role of plantations in reducing rural poverty may be overstated. Ethanol may be greener but have higher health cost. Widespread burning of ethanol as fuel may increase the number of respiratory-related deaths and hospitalizations relative to gasoline, according to a new study by Stanford University atmospheric scientist Mark Z. Jacobson. The report comes as mounting environmental concerns cloud the benefits of using ethanol as a "green" alternative to fossil fuels With Corn ethanol more costly than oil, is Jatropha a better biofuel?. Jatropha may be a more economic biofuel than corn-based ethanol, reported the The Wall Street Journal on Friday, citing research from Goldman Sachs. Analysis of the bioenergy market suggests that jatropha, which can be grown in variable conditions with little water or fertilizer, could be used to produce a barrel of fuel for around $43, less than the cost of sugar cane-based ethanol ($45 per barrel) or corn-based ethanol ($83 per barrel) currently favored in the United States. Further, because jatropha isn't edible and grows on land unsuitable for foods crops, its expansion doesn't compete with traditional food production. Cooking oil, palm oil biodiesel can reduce emissions relative to diesel. A lifecycle analysis of biodiesel by Australia's Commonwealth Scientific and Industrial Research Organization (CSIRO) shows that using palm oil derived from existing plantations can be an effective biofuel feedstock for reducing greenhouse gas emissions relative to conventional diesel fuel. However, palm oil sourced from rainforest and peatlands generating emissions 8 to 21 times greater than those from diesel. Biodiesel may worsen global warming relative to petroleum diesel. Biodiesel made from rapeseed could increase rather than reduce greenhouse emissions compared to conventional diesel fuels, reports a new study published in the journal Chemistry & Industry. Overall the researchers found that petroleum diesel and rapeseed biodiesel, presently the main biofuel used across Europe, have a similar environmental impact. The results suggest that efforts to mitigate climate change through the adoption of rapeseed biodiesel may be of little use beyond energy security. News index | RSS | Add to MyYahoo! Advertisements: Organic Apparel from Patagonia | Insect-repelling clothing |
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