Water Implications of Biofuels Production in the United States (2008) / Chapter Skim
Currently Skimming:
1 About Biomass, Biofuels, and Water
1 About Biomass, Biofuels, and Water
Pages 9-18
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From page 9... ...
In the United States, ethanol is derived mainly from corn kernels and biodiesel is derived mainly from soybeans, although other crops can serve to produce these biofuels. Approximately 4.9 billion gallons of ethanol were produced in the United States, which represents 3.6 percent of annual gasoline demand on a volume basis and 2.4 percent on an energy basis (U.S.
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From page 10... ...
Department of Energy and the U.S. Department of Agriculture concludes that the United States could produce 60 billion gallons of ethanol by 2030 through a combination of grain and cellulosic feedstocks, enough to replace 30% of projected U.S.
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From page 11... ...
. Irrigation water can come from groundwater or surface water, and groundwater can be withdrawn from either a surficial aquifer (connected directly to the surface)
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From page 12... ...
The water that is incorporated into the crops or lost to evapotranspiration is referred to as "consumptive use," because it cannot be reused for another purpose in the immediate vicinity. Rates of ET vary greatly by the type of crop.
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From page 13... ...
Surface cover is crucial in reducing sediment in runoff and limiting soil erosion. Farmers can employ a number of conservation tillage techniques that leave some portion of crop residues on the soil surface.
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From page 14... ...
PROJECTED FUTURE GROWTH OF ETHANOL PRODUCTION Recent increases in oil prices, which reflect a narrowing gap between oil supply capacity and oil demand, combined with subsidy policies have led to a dramatic expansion in corn ethanol production and high interest in further expansion over the next decade. Expansion of ethanol production to meet President Bush's call for 35 billion gallons annually by 2017 will drive increased corn production until marketable future alternatives are developed.
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From page 15... ...
A perennial crop of cellulosic biomass such as switchgrass would hold soil and nutrients in place and require lower fertilizer and pesticide inputs, thus reducing water quality impacts. There are, however, large uncertainties surrounding the production of cellulosic ethanol.
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From page 16... ...
Ugarte, University of Tennessee, written commun., July 12, 2007.
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From page 17... ...
Report by Charles Terrell (National Water Quality Specialist, Ecologi cal Sciences Division, Soil Conservation Service) and Patricia Bytnar Perfetti (Department of Geoscience and Environmental Sciences, University of Tennessee, Chattanooga)
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From page 18... ...
Courtesy of the Natural Resources Conservation Service Center, U.S. Department of Agriculture
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