July 12, 2006
Biodiesel better than ethanol but neither will meet demand, analysis says
Twin Cities, Minnesota – An analysis released by researchers at the University of Minnesota concludes that soybean biodiesel has much less of an impact on the environment and a much higher net energy benefit than corn ethanol, but neither can do much to meet the United States’ energy demands.
The researchers tracked all the energy used for growing corn and soybeans, and converting the crops into biofuels. They also looked at fertilizer and pesticide requirements, and how many greenhouses gases, nitrogen, phosphorus and pesticide pollutants were released into the environment.
The research refutes other studies that claim biofuels require more energy to produce than they provide; the study showed that soybean biodiesel returns 93 per cent more energy than is required to produce it, while corn grain ethanol provides 25 per cent more energy. Soybean biodiesel also produces 41 per cent less greenhouse gas emissions than diesel fuel, while corn grain ethanol produces 12 per cent less than gasoline.
The study also states that neither fuel can come close to meeting the growing demand for petroleum alternatives; dedicating all current U.S. corn and soybean production to biofuels would meet only 12 per cent of gasoline demand and six per cent of diesel demand, and would leave no crops for food.
The researchers suggest that biofuels from feedstocks such as switchgrass, mixed prairie grasses, and woody plants produced on marginally productive agricultural land have the potential to provide much larger biofuel supplies with greater environmental benefits, as well as biofuels produced from agricultural or forestry waste.