Some of the following documents are available as Adobe Acrobat PDFs. Download Adobe Reader.
All sustainability-related studies and reports are available on the Bioenergy Publications page.
1. What is bioenergy and how and where can I use it?
2. Does ethanol require more energy to produce than it delivers as a fuel?
3. How does biofuels production affect food and feed demand and costs?
4. What is involved in the business of producing biofuels, and getting it to market?
5. What current U.S. policies affect biofuels production and use?
6. How are plant materials converted to biofuels, products, and power?
7. Is bioenergy truly renewable?
Bioenergy is renewable energy made from any organic material from plants or animals. Sources of bioenergy are called "biomass," and include agricultural and forestry residues, municipal solid wastes, industrial wastes, and terrestrial and aquatic crops grown solely for energy purposes. Biomass is an attractive petroleum alternative because it is a renewable resource that is more evenly distributed over the Earth's surface than finite energy sources, and may be exploited using more environmentally friendly technologies. Today, biomass resources are used to generate electricity and power, and to produce liquid transportation fuels, such as ethanol and biodiesel. Ethanol is the most widely used liquid transportation fuel, or biofuel. Currently, a majority of ethanol is made from corn, but new technologies are being developed to make ethanol from a wide range of agricultural and forestry resources. Ethanol may be used as an alternative fuel, for example, in E-85 for flex fuel vehicles, and may also be used as an octane-boosting, pollution-reducing additive to gasoline, such as E-10. E-10 is widely available at gas stations in most parts of the U.S. Although availability of E-85 is more limited, use of E-85 is growing and there are currently more than 7 million vehicles on the road today that can the alternative fuel. For a list of vehicles that use E-85 and the locations of fueling stations, visit the Alternative Fuels and Advanced Vehicles Data Center at http://www.eere.energy.gov/afdc/.
For more information on bioenergy, click on the following links:
Ethanol has a positive energy balance. The energy content of ethanol is greater than the fossil energy used to produce it. This balance is constantly improving with new technologies. Over the last 20 years, the amount of energy needed to produce ethanol from corn has significantly decreased because of improved farming techniques, more efficient use of fertilizers and pesticides, higher-yielding crops, and more energy-efficient conversion technology.
DOE's efforts on biofuels focus exclusively on developing non-food/feed based cellulosic feedstocks and ethanol production technologies.
Corn and soybeans, the major commodity crops, are only one possible source of biofuels. As researchers develop new, cost-effective methods for converting biomass material to liquid transportation fuels, a significant amount will be made from more abundant cellulosic biomass sources, including crop and forestry residues, energy crops such as switchgrass and sorghum, and sorted municipal wastes.
Crops grown to produce biofuels in the United States can also utilize a variety of agricultural lands. Future cellulosic crops will have the added benefit of being able to grow on marginal soils not suited for traditional agriculture. Less than one percent of farm land globally is currently used to grow biofuels crops.
DOE's approach to biorefining seeks simultaneously to maximize biopower and side-stream bioproduct production within the cellulosic fuel production system. Most corn demand results from cattle and poultry production. One major bioproduct of traditional corn ethanol production has always been Distiller's Dried Grains (DDGs) and/or Distiller's Dried Grain Solubles (DDGS), which can be used as a high-protein animal feed.
In addition, as found in a recent Texas A&M study, a variety of factors not listed above significantly affect food and feed demand and prices:
- high oil prices (used both in transportation and production of food);
- increasing demand from developing economies; and
- speculative fund activities in futures markets.
For more information, please review the following reports and press releases:
- The Effects of Ethanol on Agricultural Food and Feed (April 2008), Texas A&M University Agricultural Food and Policy Center (PDF 2.3 MB)
- "A Sustainable Biofuels Consensus", March 2008 (PDF 147 KB) Global Bioenergy Partnership
- Biomass as Feedstock for a Bioenergy and Bioproducts Industry: The Technical Feasibility of a Billion-Ton Annual Supply, April 2005 (PDF 8.5 MB) U.S. Departments of Energy & Agriculture
- DOE Responds to TIME Magazine's Criticism of Ethanol, April 2008
- New Studies Portray Unbalanced Perspective on Biofuels: DOE Committed to Environmentally Sound Biofuels Development, May 2008
Several biofuels industry organizations exist to advocate for technologies which are already commercial, and to collaborate internally and externally in support of biofuels markets. They are listed on this Web site's Related Links page.
DOE's main R&D focus on efficient cellulosic biofuels production does include several project partnerships with industry. More information about ongoing projects is provided on this Web site's Financial Opportunities - Past Solicitations page.
Those interested in investing in biofuels technologies and markets should review the above information, and also visit the Funding Opportunities page, which provides current listings of open, competitive DOE solicitations for cutting-edge R&D efforts, as well as links to funding sources outside the Bioenergy Technologies Office.
Congress passed energy legislation, known as the Energy Independence and Security Act of 2007, which raises standards for vehicle fuel economy and mandate that U.S. transportation fuel include 21 billion gallons of advanced biofuels by 2022 and 2 billion gallons as soon as 2012. The legislation further requires that these advanced biofuels must achieve at least a 50% reduction in life-cycle greenhouse gas emissions.
For more information, please click on the following link:
Extensive information regarding current DOE R&D focus and additional bioenergy applications is available on this Web site's Technologies pages.
For more information on current commercially-available technologies visit the Alternative Fuels and Vehicles Data Center Web site.
Bioenergy is considered truly renewable because its source—biomass—is a replenishable resource. Vegetative matter will continue to grow as long as it is planted. Additionally, biomass energy recycles carbon dioxide during the plant photosynthesis process and uses it to make its own food. In comparison to fossil fuels such as natural gas and coal, which take millions of years to be produced, biomass is easy to grow, collect, utilize and replace quickly without depleting natural resources.
Bioenergy is not only renewable, but is also sustainable.
Greenhouse gas (GHG) emissions will decrease dramatically as biofuels of the future are increasingly made from cellulosic feedstocks and as the associated farming, harvesting, transport, and production processes use progressively more clean, renewable energy sources.
- U.S. Department of Energy studies show corn ethanol results in 19% fewer GHG emissions, on average, when compared with petroleum. Cellulosic ethanol has the potential to reduce GHG emissions by up to 86%.
- EPA is leading efforts to evaluate lifecycle emissions from renewable fuels, which will incorporate both direct and indirect land-use and other impacts, as mandated by EISA.
- The USDA plans to spend an estimated $12.1 billion in 2008 on protecting and enhancing the nation's natural resource base and environment, by:
- Protecting and ensuring healthy watersheds, soil quality, forests/grazing lands, and habitats; and
- Researching ways to increase crop yields, improve drought resistance, and reducing the need to use fertilizer, herbicide, and pesticide and irrigation.
- We now have a U.S. interagency sustainability group to facilitate strategic planning, coordinate federal activities, and develop domestic sustainability goals and benchmarks.
- We are collaborating with international partners on biofuels sustainability issues.
For more information on the sustainability of biofuels:
- Biofuel and Global Biodiversity, May 2008, a report by the Institute for Agriculture and Trade Policy
- Bioenergy Technologies Office responses to article by Searchinger et al. in Sciencexpress, "Use of U.S. Croplands for Biofuels Increases Greenhouse Gases through Emissions from Land Use Change," February 7, 2008