Bio-Fuels Page 2|
Agricultural & Biological Risk Assessment
Montana State University
Who utilizes bio-fuels and why are they not overtaking the use of oil?
Brazil has long been the world leader in ethanol production by utilization of their sugarcane crop. In the United States, maize-based ethanol is increasing by 30% a year and China is catching up. China is in the process of building the world's largest ethanol plant and they have plans to build another one just as large. A big producer of biodiesel is Germany. They are increasing their output by 40-50% a year. France produces biodiesel and ethanol, and plans to triple their output by 2007. Canada is also producing ethanol. Many of these countries use the bio-fuel in conjunction with gasoline. Europeans use a B5 mixture that is 5% biodiesel and 95% standard diesel mixture. In the U.S., a typical ethanol blend is E10 or gasohols, which are 10% ethanol and 90% standard gasoline. There are blends of 20% ethanol and in California; they have 100% biodiesel that contains additives so it is usable at -20°C. Pure ethanol can damage standard gaskets and hoses, but in Brazil carmakers are producing cars that can run on mixtures of 75% ethanol and 25% gasoline, and in the U.S., there are cars that can run on E85 fuel. Compared to mineral fuels, bio-fuels are still at small output and usage levels, but with the rising oil prices, this may change (The Economist 2005).
Biodiesel versus ethanol
There is a constant debate over the efficiency of either biodiesel or ethanol. The debates go back and forth on environmental benefits, land usage, cost to consumers, and energy output. Europeans may think bio-diesel is better for them because of the cars they already utilize, and Brazilians may stick to ethanol because they have the climate and land suitable for growing sugarcane. In either case, the options may change and the source of fuel may change but what is important is alternatives need to continually be researched and tested. It is difficult to determine which is better, bio-diesel or ethanol because location and government play a large part. Biodiesel may prove practical in Europe, where more cars run on diesel, and ethanol will likely remain the transportation bio-fuel of choice in the U.S., given this country's gasoline-based infrastructure (Science News 2005). The U.S. may utilize more bio-fuel, but soybeans grown in Iowa are now an attractive source for biodiesel and three biodiesel plants are in operation with more planned (Brown 2006).
Another possible way to produce ethanol is to use enzymes to break down cellulosic materials. Switchgrass or fast growing or hybrid trees would be alternatives to corn, sugar beets, and sugarcane. Switchgrass can be grown on non-arable land and the ethanol yield per acre is calculated at 1,150 gallons, higher than for sugarcane. For switchgrass the net energy yield is four, which is above corn (1.5), but less than sugarcane (8) (Brown 2006).
Butanol may be another alternative source for fuel. Butanol is a form of alcohol derived from fermentation of corn with higher energy content than ethanol. Butanol is capable of fueling vehicles with no engine modifications and does not have to be blended with petroleum. It can be used in combustion engines as well as diesel engines and is essentially non-polluting. The negative aspect of butanol is it has a horrible odor that can persist for a long time. Butanol is not a popular or known alternative fuel today because, like bio-fuels, its production lost momentum when petroleum fuels came down in price. The production of butanol is labor intensive and only low yields are recovered. Unlike ethanol, butanol can be pumped through our current pipelines to reach fuel outlets and is less corrosive and safer to handle. With the advances in biotechnology, the interest in fermentation production of chemicals has been regained and there is an interest to increase the yield and production rates of this chemical (Ramey 2004).
Many agricultural biotechnology companies are working to produce ethanol from biotech derived crops. With biotechnology involved in ethanol production, this may help to strengthen the case for ethanol because there are potentially greater benefits to the environment by using biotech crops.
Brown, L. 2006. How food and fuel compete for land. The Globalist. Available at: http://www.theglobalist.com/StoryId.aspx?StoryId=5077.
Des Garennes, C. 2005. Lack of pumps limiting E85s appeal. News-Gazette. Available at: http://www.news-gazette.com/news/local/2005/08/03/lack_of_pumps_limiting_es _appeal/
Iogen Corporation. 2006. http://www.iogen.ca/
Lee, L. 2004. Interim report of the role of biomass in America's energy future. National Resources Defense Council. Available at: http://www.ethanol-gec.org/information/briefing/3.pdf
Moreira, N. 2005. Growing expectations: new technology could turn fuel into a bumper crop. Science News. 168: 218-220.
Murray, D. 2005. Ethanol's potential: looking beyond corn. Earth Policy Institute. Available at: http://www.earth-policy.org/Updates/2005/Update49_printable.htm
Pimentel, D., and Patzek, T.W. 2005. Ethanol production using corn, switchgrass, and wood; biodiesel production using soybean and sunflower. Natural Resources Research. 14: 65-76.
Ramey, D. 2004. Butanol, advances in biofuels. Available at: http://www.lightparty.com/Energy/Butanol.html
The Economist. 2005. Special report biofuels; stirrings in the corn fields. The Economist. 375: 71-73.