Bryan Russell Baldridge (General Chemistry)
Alternative Energy: Ethanol
Ethanol, also called ethyl alcohol, is used as a supplement to gasoline. Ethyl alcohol is fermented from corn, grains, or it is chemically extracted from ethylene. In recent years, ethanol has been a controversial issue. The debate is over the “net energy” content of ethanol production. Does it take more energy to produce the ethanol than what is in the final product we put in our vehicles (journey.com)? David Pimental, a Cornell University agricultural expert, has calculated that powering the average U.S. automobile for one year on ethanol derived from corn would require eleven acres of farmland, the same farmland that could be used to grow a one-year supply of food for seven people (Health and Energy.com). An interesting fact from health and energy, states: “If all the automobiles in the United States were fueled with one hundred percent ethanol, a total of about ninety-seven percent of United States land area would be needed to grow the corn. Corn would cover nearly the total land area of the United States.”
Ethanol as an alternative energy source does have benefits. Compared with gasoline, ethanol produces twelve percent less greenhouse gases (U.S.A Today.com). Ethanol is a renewable energy source, the corn used for production can be grown year after year. One of the biggest advantages of ethanol over gasoline is the reduced dependence on imported oil (wise geek.com). The downsides of ethanol use are almost as great as the advantages. The high overhead cost to produce ethanol, the amount of land used for production, and the depletion of nutrients from soil are among some of the disadvantages.
The process for obtaining ethanol is different than the other processes for obtaining more conventional fuels such as gasoline. There are two production processes: wet milling and dry milling. In dry milling, the corn is ground into flour. The flour is then mixed with water to form mash, the mash is then heated and cooled. Yeast is added to begin the fermentation process. The fermented mash is distilled to two hundred proof. Carbon dioxide is a byproduct of the fermentation process. The carbon dioxide involved is captured and used for the production of soda and dry ice (ethanol rfa.org). The wet milling process is similar to the dry milling process. The production of ethanol has increased over the years, in 1980, 175 million gallons of ethanol were produced, in 2009, 10,750 million gallons were produced (ethanol rfa.org).
Ethanol has a chemical composition of (C2 H5 OH). The ethanol that powers our cars is called E85, which is 85 percent ethanol and 15 percent gasoline. Ethanol is not to be confused with methanol (CH3 OH), an alcohol similar to ethanol that powers vehicles in California ( Zumdahl).
The debate over the production of ethanol as an alternative energy is a debate that will not be resolved in the near future. There are too many positive advantages for ethanol production and use, as well as too many disadvantages. Ethanol will continue to be produced and people will continue to use ethanol, until a better less controversial form of clean alternative energy is made available.
