Cellulosic ethanol is produced from lignocellulose, which unlike most ethanol produced in North America which comes from corn, is derived from non-food materials such as
- Switch grass
- Miscanthus (elephant grass)
- Oat/barley straw
- Sugarcane bagasse
- Hard wood chips
According to U.S. Department of Energy, another of the benefits of cellulosic ethanol is that greenhouse gas emissions (GHG) are reduced by 85% compared to gasoline. In comparison ethanol derived from corn may not reduce greenhouse emissions at all. According to a University of Minnesota study, corn ethanol may be even worse for air quality than gasoline. The study concluded that the total environmental and health costs of making a gallon of gasoline was about 71 cents, compared with a range of 72 cents to $1.45 for corn-based ethanol, and 19 to 32 cents for cellulosic ethanol, depending upon the technology and type of plants used.
In Brazil about 25% of the fuel used by automobiles is ethanol derived from sugar cane. Brazil is considered to have the world's first biofuels economy and many people believe sugar cane ethanol is the most successful alternative fuel. The sugar cane-waste (bagasse) is used for heat and power, so that sugar cane ethanol is very competitive pricewise. Sugar cane ethanol also has a high energy balance compared with corn ethanol. There are no longer any automobiles in Brazil running on pure gasoline. Since 2007 the mandatory blend of gasoline and ethanol is 25% ethanol and 75% gasoline. However, cane sugar can be used to produce food as well as cachaça of which 1.5 billion liters are consumed annually in Brazil.
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