Ethanol:Liquid Pork, Holy Water or Fields of Gold?Kris HoffMike ElderXinkai WuCE 5212Introduction The United States' increasing dependence on foreign oil is widelyrecognized as one of the nation's biggest problem. One possible solution, ethanol, is a form of biofuel. Ethanol is grain alcohol, produced from crops of grain and corn. Ethanol helps reduce our dependence upon foreign imports By mixing ethanol with gasoline it decreases the fuel's cost, increases thefuel's octane rating and decreases gasoline's harmful emission. However many are opposed to the use of ethanol due to its low energyinput to output ratio. This case study focuses on: Corn and cellulosic ethanol: analyzing the efficiency, economic issues,environmental impacts, production, the effect on car industry, the currentaffairs and future concerns of ethanol. Case Study: Brazil’s ethanol program which has been active longer than anyother country’s.Corn EthanolDifferent Views“It’s a sinister idea to convert food into fuel”~Fidel Castro“Renewable ethanol represents a clearopportunity to grow a significant portion ofour own fuel locally and begin to break thehold imported fuels have on us.”~Mike MayDefinition Ethanol - a flammable, colorless,slightly toxic chemical compound, and isoften referred to simply as alcohol. molecular formula -> EtOH, CH3CH2OH, C2H5OH empirical formula -> C2H6O Corn-Based Ethanol - is ethanolproduced from corn through industrialfermentation, chemical processing anddistillationProduction Dry Milling Starts with liquefied cornstarch produced by heating cornmeal with water and enzymes. This starch is converted to sugars with a second enzyme andthen fermented by yeast into ethanol and carbon dioxide. Wet Milling Separates the germ, fiber and protein from the starch beforeit is fermented into ethanol.Usage Pure ethanol fuel is not used as a motorfuel; rather it is mixed with unleadedfuel. E85 is 85% ethanol and 15% unleadedgasoline E15 is 15% ethanol and 85% unleadedgasoline.E85 Flex Fuel VehiclesBenefits Reduce the environmental impacts of gasolineconsumption Renewable Environmentally friendly Cleaner than gasoline Reduces harmful tailpipe emissions Helps U.S. agriculture development Reduces dependence on foreign oilsProblems Raises corn prices Low efficiency Temporary solution Negative effects on US livestock Use of fossil fuels throughoutproduction Sustainability Need for ethanol pipelineCorn PricesPolicies 1990 Clean Air Act Amendments Most recent energy bill By 2012 the US must use at least 7.5 billiongallons of renewable fuel per year Currently a push is being made for 15 billiongallons per year Minnesota law requires change in amount of ethanol in allgasoline sold in the state from 10% to 20% by2012Rise of EthanolRise of EthanolEthanol vs. GasolineCellulosic Ethanol “To meet President George Bush’sambitious goal which required toreducing the nation's dependency onforeign oil by producing 35 billiongallons a year of renewable andalternative fuels by 2017, cellulosicethanol is an attractive alternative”.What is Cellulosic Ethanol Unlike corn ethanol, which is only producedfrom sugars and starches, cellulosic ethanolcan be produced from a wide variety ofcellulosic biomass feedstock includingagricultural plant wastes (corn stover, cerealstraws, sugarcane bagasse), plant wastesfrom industrial processes (sawdust, paperpulp) and energy crops grown specifically forfuel production, such as switchgrassHow is CellulosicEthanol Made? Step 1: Break down cell walls of the rawplant feedstock by thermochemical treatmentand make the cellulose accessible; Step 2: Add enzymes to convert the celluloseand hemicellulose molecules into the simplesugars glucose and Xylose; Step 3: Convert the sugar into a mixture ofethanol and water by fermentation yeast; Step 4: Refine and purify the ethanol.What Are the Advantagesof Cellulosic Ethanol? Abundance: Cellulosic ethanol has no this limit because ituse the feedstock such as wheat straw, grass, and woodchips, as the source which is cheap and abundant. Expected to be less expensive and more energy-efficient than other ethanol because it can be made fromlow-cost feedstock: Table 1: Cost (Data Source: Zfacts, 2004)What Are the Advantages ofCellulosic Ethanol? The third advantage of cellulosic biofuel isthat it will soften impact to world foodprice Percentage changes in world prices of feedstock crops under threescenarios (Data source: Rosegrant, M. W et al., 2006)What Are the Advantages ofCellulosic Ethanol? The fourth advantage of cellulosic biofuel is that it reduces greenhousegas emission compared to grain based ethanol The research done by Farrell A. E (2006) indicated that “GHG (greenhousegas) emissions from ethanol made from conventionally grown corn can beslightly more or slightly less than from gasoline per unit of energy, butethanol requires much less petroleum inputs.What Are the Problems ofCellulosic Ethanol? Conceptually, it is easy to convert cellulose to ethanol.Scientists have long known how to turn trees into ethanol,but doing it profitably is another matter (Evan Ratliff,2007). The problem is that cellulose is a tough molecule to breakdown. To deal with this issue, there are three potential methods. One is advocated by Lee Lynd, who is trying “to create abacterium that serves as an all-in-one fuel factory, instead ofusing enzymes to make sugar out of plant material and then usingyeast to convert that sugar to ethanol” (Evan Ratliff, 2007). The second method is to reduce the cost of enzyme mixture byproducing the new enzymes which can be much faster. The third potential method is to try to find the better enzymes.Case Study: Brazil 1973 – Yom Kippur War OAPEC – Arab OPEC members,Egypt,Syria OPEC Oil Embargo US, Western allies, Japan Results – Inflation, explosion in oil pricesCase Study: Brazil 1975 - National Alcohol Program Programa Nacional do Álcool (Proálcool)Case Study: Brazil Objectives of Proálcool Decrease Brazil’s dependence on foreign oilby replacing gasoline consumption withethanol consumption Stimulate economy by producing fuel fromlocal sugarcane as opposed to foreign oilCase Study: Brazil Gasohol ~24% ethanol, 76% gasoline All automobile fuel in Brazil incorporates atleast 22% ethanol E95,
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