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Commercial production of biofuels. Ethanol from sugar cane. Ethanol from corn. Biodiesel from oils. Sugar cane to ethanol. The Brazil Story. http://www.youtube.com/watch?v=lTu5apw7AjQ&NR=1. Sugar cane, sugar cane bagasse. Sugar cane bagasse. Processing. Ethanol. Sucrose.
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Commercial production of biofuels Ethanol from sugar cane Ethanol from corn Biodiesel from oils
Sugar cane to ethanol The Brazil Story http://www.youtube.com/watch?v=lTu5apw7AjQ&NR=1
Sugar cane, sugar cane bagasse Sugar cane bagasse Processing Ethanol
Sucrose • Sucrose accounts for little more than 30% of the chemical energy stored in the mature plant; 35% is in the leaves, which are left in the fields during harvest, and 35% are in the fibrous material (bagasse) left over from pressing • Sucrase or acid are needed to break down sucrose into glucose and fructose α-D-glucopyranosyl- (1↔2)-β-D-fructofuranoside
Sugar cane bioethanol • Brazil produces about 7 billion gallons of ethanol from sugar cane • Production cost $0.87/gallon, the lowest in the world • Fossil fuel energy used to make the fuel (input) compared with energy in the fuel (output) 1:8 • Green house emission during production and use 56% less compared with gasoline
History • 1920 utilization of ethanol as a transportation fuel • Early 1970, • 1973-oil embargo (oil 3x more expensive) • 1974-sugar prices • Late 1975 Brazilian National Alcohol program (20% blend) • Mid 1980 • All the cars sold in Brazil ran on alcohol • Early 1990 • Oil • Sugar
2003 Total Flex Car (gasoline and ethanol) Gol-Volkswagen Currently 85% of cars are flex History
Sugar cane • Harvest after 1 year to 18 months • Harvest starts in April • 7 harvests before replanting • Harvested by hands or machinery • 20% of sugar cane are sugars • 600-800 gallons of ethanol/acre (more than 2x compared with corn)
Problems • Environmental problems • Deforestation • Burning the cane pre-harvesting • Use of pesticides and herbicides • Utilization of fields next to the rivers (against Brazilian law) • Social problems • Pay • Hot, dirty and backbreaking • Snakes • Cuts • Air quality
Rise of bioethanol (history) • H. Ford 1908 • Sugar cane ethanol 1920 • OPEC oil embargo (1973) • Methyl tertiary-butyl ether MTBE (started in 1992, phased out in 2000) (2-methoxy-2-methylpropane ) • Good blending • Increase octant number • Cheap, produced from natural gas • Toxicity • Oil in Middle East $$$$
Corn plant Corn kernel (without the fibre)-starch alcohol Corn fibre-lignocellulosic alcohol Corn stover-lignocellulosic alcohol
US ethanol production US ethanol product is currently about 9 billion gallons/year – largest in the world!
Corn • One bushel of corn (56 pounds after husks and cobs are removed) provides: • 31.5 pounds of starch or • 33 pounds of sweetener or • 2.8 gallons of ethanol + • 13.5 pounds of gluten feed • 2.6 pounds of gluten meal • 1.5 pounds of corn oil
Corn to ethanol plants in US Based on August 30th, 2006
Ethanol subsidy • Ethanol subsidy totals about $5 billion for 9 billion gallons of ethanol ($0.55 per gallon) • 51cents per gallon-federal blenders credit • Corn subsidies • Import tariff on foreign ethanol of 54 cent/gallon + 2.5% of import value import
Ethanol versus oil subsidy • Since 1968 ethanol industry had received $11.6 billion in tax incentives • Since 1968 oil industry had received over $150 billion in tax benefits. • Oil industry produced 1,068 times more energy • Subsidy per unit of energy was 54 times higher for ethanol (ethanol gets 54 cents oil gets 1cent). US General Accounting Office
Problems • Environmental problems • Greenhouse gas emission • Ethanol plants burn natural gas or coal to create the steam, adding to fossil fuel emission with CO2 from fermentation • Energy value • Pesticides, herbicides (nitrogen runoff from fertilizers) • Fertilizers (N, made with natural gas and diesel farm machinery) • Water demands: 3.6-6gallons of water/1 gallon of ethanol • Social problems • Competing with food industry • Doubling the price of corn (food riots in Mexico)
Problems land availability • “The average US automobile, traveling 10,000 miles a year on pure ethanol (not a gasoline-ethanol mix) would need about 852 gallons of the corn-based fuel. This would take 11 acres to grow, based on net ethanol production. This is the same amount of cropland required to feed seven Americans” David Pimental Cornell University
Problems land availability • “If all the automobiles in the United States were fueled with 100 % ethanol, a total of about 97% of US land area would be needed to grow the corn feedstock. Corn would cover nearly the total land area of the United States” David Pimental Cornell University