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biofuels food versus fuel dr tapsak hsc203 x4893 national teach in on global warming feb 5 2009 n.
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How green are biofuels? PowerPoint Presentation
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How green are biofuels?

How green are biofuels?

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How green are biofuels?

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  1. Biofuels: Food versus Fuel?Dr. Tapsak, HSC203, x4893National Teach-in on Global Warming, Feb. 5, 2009

  2. How green are biofuels?

  3. In 1908, Ford’s Model T had a carburetor adjustment that allowed the vehicle to run on ethanol. • In the 1930s, more than 2000 service stations in the Midwest sold ethanol made from corn. • By the 1940s, WW2 prompted governments to commandeer whiskey distilleries for ethanol fuel production. • During the 1970s oil crisis, ethanol was blended into gasoline to form gasohol (E10). Interesting ethanol facts! http://www.nesea.org/greencarclub/factsheets_ethanol.pdf, accessed 2/3/09

  4. How is ethanol currently produced from corn? • Milling • Liquefying the Cornmeal • Enzyme Hydrolysis • Yeast Fermentation • Distillation • Dehydration https://www.eere-pmc.energy.gov/PMC_News/images/ethanolmythpic.jpg, accessed 2/3/09

  5. Where is ethanol currently produced?

  6. Switch grass and wood byproducts contain fermentable sugars, but they are locked up in complex structures. Plant matter (biomass) consists of three key polymers: Cellulose (35 to 50%), hemicellulose (20 to 35%), and lignin (10 to 25%). http://genomicsgtl.energy.gov/benefits/cellulosicethanol.shtml, accessed 2/3/09

  7. How is ethanol currently produced from biomass? • Mechanical Preprocessing • Pretreatment • Solid-Liquid Separation • Fermentation of Hemicellulosic Sugars • Enzyme Production • Cellulose Hydrolysis • Fermentation of Cellulosic Sugars (Glucose) • Distillation • Dehydration http://genomicsgtl.energy.gov/benefits/cellulosicethanol.shtml, accessed 2/3/09

  8. According to Dr. David Pimental, Cornell University, powering the average U.S. automobile for one year on ethanol (blended with gasoline) derived from corn would require 11 acres of farmland. • Ethanol can not be effectively transported by pipeline. • More energy is required to produce ethanol than the energy that actually is in it. • Ethanol subsidies are highly politicized. What are the challenges we face? http://genomicsgtl.energy.gov/benefits/cellulosicethanol.shtml, accessed 2/3/09