Biofuels are a type of renewable fuel, usually found in liquid form, that have been distilled and produced from a variety of grains and animal fats. These elements, the base compounds for biofuels, are referred to as biomass, with the most popular being corn. Other forms of biomass can include barley, sugar cane, soybeans, canola, and other traditional row crops. The two most well-known biofuels are ethanol and biodiesel.
Ethanol is a clear alcohol that is virtually indistinguishable from the type of alcohol one finds in whiskey or beer. Its base is a pure grain alcohol, identical in content to homemade liquors such as the moonshine or white lightning produced in well-hidden stills during the era of American prohibition. As of 2009, ethanol is being used primarily as a federally mandated additive to gasoline. The stated purpose of ethanol production is to reduce pollution, greenhouse gas emissions, and dependence upon both petroleum-based fuels and the countries that provide them.
However, there are questions regarding the environmental wisdom of increased ethanol production. While it is no doubt a renewable fuel, it utilizes vast amounts of grain that were formerly allocated toward producing feed for animals or food for direct human consumption. This has led to substantial, worldwide price increases in almost all commercially available foods, particularly breads, cereals, pastas, pork, fowl, and beef.
Furthermore, as federal mandates for ethanol use expand, additional forested land is being cleared for agricultural purposes. Since trees absorb carbon dioxide, their harvest could lead to an even greater greenhouse effect. Last but not least, the increased production of biomass grains entails an increased use of herbicides, pesticides, fertilizers, and emissions from farm equipment.
Biodiesel is similar to ethanol in that it is a renewable liquid fuel, however it is most commonly created from soybeans, canola, or animal fat. Unlike undiluted ethanol, which will destroy the rubber seals and gaskets in a standard car engine, biodiesel is very close in chemical composition to petroleum-based diesel. It can either be blended with this fuel, or used as a direct substitute.
However, the process of producing biodiesel poses the same problems as ethanol in terms of reallocating food sources and converting forests and grasslands to agricultural use. While renewable fuels are certainly a wise idea, there is much debate concerning the positives and negatives of biofuels. Though widely touted as being superior to petroleum-based fuels, they are far from clean. There is some fear that biofuels, if produced in excess, could lead to an acceleration of the very problems they were intended to cure.