Natural oils from crops like soybeans and corn can produce a renewable, domestic engine fuel called biodiesel. Biodiesel has been hailed as an alternative fuel that can reduce carbon dioxide emissions and the United States' dependence on foreign oil. However, the industrial use of biodiesel is relatively new and largely untested over long periods of time. There are some significant drawbacks to over-farming these new cash crops for an easy economic fix.
A study by the U.S. Department of Energy revealed that a 78.5 percent reduction in carbon dioxide emissions was linked to the production and use of biodiesel fuel.
A July 2008 study performed by a World Bank research panel found that the production of biodiesel fuel increases the prices of food commodities. The resulting effect is a global "food versus fuel" dilemma.
For every unit of energy required to make a gallon of biodiesel fuel, 3.24 units of energy are gained. This ratio represents a positive energy balance.
Over-farming biodiesel crops can result in topsoil erosion and creating new biodiesel farmland can result in the destruction of natural habitats.
In a 2001 study, the U.S. Department of Energy found that an annual increase in the demand for soy-based biodiesel by 200 million gallons would create an annual net farm income increase of $300 million a year.
When considering the task of storing biodiesel, one concern is that it oxidizes quicker than regular petroleum-based fuels. Biodiesel turns into a semisolid gel-like mass in engines that are operated only occasionally.
