Several years ago during a tour of a ethanol plant in Aurora, South Dakota, corn ethanol was hailed as the “it” technology. As fuel prices continue to rise, concerns about greenhouses gasses grew, and hybrid vehicles became a hit, corn ethanol looked to be the solution to numerous problems. However, as new technology has developed, the murmur of using other sources like switchgrass or sugarcane has grown into a loud roar.
Although ethanol is a relatively new form of energy production, numerous studies have been conducted regarding the actual efficiency of ethanol production. “Ethanol and the Local Community,” a 2002 study from AUS Consultants stated that construction of an ethanol plant would cost $60 million, while growing the local economy by $110 million annually. The study also concluded that the estimated annual local and state government tax revenue would increase by $1.2 million because of ethanol production. U.S. ethanol production sounds promising.
Where the ethanol problem arises is in the current source used for ethanol production in the United States. Corn, a vital feed stuff for livestock industries, dominates ethanol production. As a result, feed prices have skyrocketed for livestock producers, putting more pressure on already slim profit margins faced by the agricultural industry. The demand for corn had grown exponentially in the last decade, and marginal farm land has been put into production to produce the resource intensive crop. Most of the added corn acres are from land that is better suited for less nutrient demanding crops or from wildlife habitats. Ethanol is a competitive price option at the pump due to the high amount of government subsidizes received by the ethanol industries. Consequently, many renewable advocates have realized that corn may not be the best source for ethanol production.
Current research is being devoted to developing cellulosic ethanol technology, reducing the costly corn ethanol. Possible sources for cellulosic ethanol include wheat straw, corn stalks and husks, algae, sugarcane, and switchgrass. Regardless of the source used, corn ethanol and cellulosic ethanol have identical chemical components.
The Living History Farm of York, Nebraska (www.livinghistoryfarm.org), has an excellent article regarding the difference ethanol sources. Figure 1 shows a picture of the large root system in switchgrass that stores the necessary sugars needed for ethanol production. Figure 2 is a picture of developing algae in El Paso, Texas, as another possible source for ethanol production. The largest issue concerning cellulosic ethanol is utilizing enzymes capable of converting the carbohydrates into actual alcohol. Consequently, American Coalition for Ethanol states that cellulosic ethanol is only in the developmental stages of commercial use in the U.S. .
Figure 1: Switchgrass from “Future Sources of Ethanol,” Living History Farm, York, NE.
Figure 2: Algae from “Future Sources of Ethanol,” Living History Farm, York, NE.
Although cellulosic ethanol is still in the early stages of development in the U.S., other countries, like Brazil, have already seem positive results in their use of sugarcane to produce ethanol. Corn ethanol provided a start renewable fuel, but will begin to be replaced by other sources that are less energy intensive to grow and harvest.
