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BioFuels and the Environment

Basic Information

What are Biofuels?

Biofuels are fuels derived from renewable biological materials such as ethanol from corn kernels, corn stover, perennial grasses, woody biomass, and algae, and diesel from soy beans. Currently available biofuels are made from sugar crops (sugarcane, sugarbeet), starch crops (corn, potatoes), oilseed crops (soybean, sunflower, rapeseed), and animal fats. Sugar and starch crops are converted through a fermentation process to form bioalcohols, including ethanol, butanol, and propanol. Oils and animal fats can be processed into biodiesel. Ethanol is the most widely used bioalcohol fuel. Most vehicles can use gasoline-ethanol blends containing up to 10% ethanol (by volume). Flexible fuel vehicles can use gasoline-ethanol blends containing up to 85% ethanol. Currently there are only about 700 fueling stations in the U.S. that offer E-85 fuel, most of which are in the upper Midwest. [Source: SmartWay Biodiesel Fact Sheet]

Second generation biofuels, or cellulosic biofuels, are made from cellulose, which is available from non-food crops and waste biomass such as corn stover, corncobs, straw, wood, and wood byproducts. Third generation biofuels use algae as a feedstock. Second and third generation biofuels are not yet produced commercially.


Section 204 of the Energy Independence and Security Act (EISA) of 2007 (Public Law 110-140) calls for the U.S. Environmental Protection Agency to prepare a Report to Congress to assess and address the impacts to date and likely future impacts of the increased use of biofuels as required by the Clean Air Act, section 211(0). Environmental issues (e.g. hypoxia, sediment, nutrient, and pathogen levels in water), resource conservation issues (e.g. soil conservation, water availability, energy recovery from secondary materials, and ecosystem biodiversity) and growth and use of cultivated invasive or noxious plants will be included.

The Energy Independence and Security Act (EISA) mandates increased production of biofuels (fuels derived from renewable biological materials). Recognizing the potential impacts of this change, Congress requires the U.S.EPA, under EISA Section 204, to assess and report every three years on the current and potential future environmental and resource conservation impacts associated with increased use of biofuels. EPA is now developing its first triennial Report to Congress on this issue. The report will:

  • Focus on the six biofuels (listed above).
  • Analyze impacts across the full life cycle of biofuels, including the production and transportation of feedstocks and the production, distribution, and use of biofuels.
  • Environmental impacts, including air, water, and soil quality.
  • Resource conservation impacts, including soil conservation, water availability, land use changes, and ecosystem health and biodiversity.
  • Environmental and agricultural impacts resulting from the growth and use of cultivated invasive plants.

Replacing fossil fuels with biofuels - fuels produced from renewable organic material - has the potential to reduce some undesirable aspects of fossil fuel production and use, including conventional and greenhouse gas (GHG) pollutant emissions, exhaustible resource depletion, and dependence on unstable foreign suppliers. Demand for biofuels could also increase farm income. Biofuel production and use has drawbacks as well, including land and water resource requirements, air and ground water pollution, and increased food costs. Depending on the feedstock and production process, biofuels can emit even more GHGs than some fossil fuels on an energy -equivalent basis. Biofuels also tend to require subsidies and other market interventions to compete economically with fossil fuels, which creates deadweight losses in the economy.

In addition to the EISA Act, in May, 2009, President Obama established the Biofuels Interagency Working Group - co-chaired by USDA, DOE, and EPA, and with input from many others - to develop a comprehensive approach to accelerating the investment in and production of American biofuels and reducing our dependence on fossil fuels. Thus far the Working Group released the report: Growing America's Fuel - a new U.S. Government strategy for meeting or beating the country's biofuel targets. The report is focused on short term solid government solutions supporting the existing biofuels industry, as well as accelerating the commercial establishment of advanced biofuels and a viable long-term market by transforming how the U.S. Government does business across Departments and using strategic public-private partnerships.


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