A Study on the Environment and Energy Effects of Biodiesel

Based on the statistic data of DOE(the U.S. Department of Energy), we analyze the energy cycle of biodiesel by the method of so called cycle analysis. It includes the energy consuming and yielding, emissions and tailpipe emissions. The result shows that the fossil energy ratio of biodiese is four times that of petroleum diesel; the life cycle emissions of CO 2 are much lower. Biodiesel reduces net CO 2 emissions by 78% compared to petroleum diesel. On the other hand, the emissions of the tailpipe such as CO, HC and PM are much lower for biodiesel than those for petroleum diesel except the NO x , which increasing by 8.89% instead.