Executive Summary
Industrial and developing countries alike have begun investigating the proliferation of biofuels. For industrialized nations, biofuels represent a way to move away from ever increasing oil prices, energy security concerns and climate change. For developing countries, biofuels can help to stimulate rural development, create jobs, and save foreign exchange.
Ethanol is most often and successfully produced with sugar and starch-based crops, while biodiesel is most often and successfully produced with oilseed crops. The use of food crops for biofuels has become controversial, since it has the potential to increase food prices. The "food vs. fuel" debate has prompted research into "second generation" biofuels. These are energy sources derived from whole plants and trees, including materials often classified as waste. Emerging second generation technologies include biobutanol, algae biodiesel, and biomass gasification.
While the word "biofuels" is most often associated with ethanol and plant-oil based biodiesel, it encompasses other fuels derived from plant-based sources. Additionally, there are two main categories of biofuel: Traditional and modern.
- Traditional biofuels. This term describes the combustion of wood, animal waste, and crop residues for household cooking and heating. Traditional biofuels are used mostly by people in developing countries. Traditional biomass accounts for 80% of the global renewable energy use.
- Modern biofuels. This term refers to biomass that has been altered by conversion technologies like fermentation and gasification so as to utilize it for electricity and transportation. The modern biofuels ethanol and biodiesel comprise less than 1% of the global renewable energy use.
A key component to biofuel production is feedstocks. Feedstocks are the raw materials used in the biofuel conversion process. The main types of feedstock are sugar and starch-based crops, oilseed crops (such as soybean, rapeseed, and oil palm), wood, wastes and residues, and dedicated cellulosic crops (such as perennial grasses like switchgrass and Miscanthus). The most technologically competent and advanced ethanol production process utilizes sugar and starch-based crops, while the most technologically competent and advanced biodiesel production process is based upon oilseed crops.
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