Corn Ethanol as Energy
Corn grain is one of the major foods of the world. Grains in general provide about 80 percent of the world food calories. Today there is a per capita shortage of grains and other foods, exacerbating the serious global malnourishment problem. The World Health Organization reports that 3.7 billion people are malnourished today—nearly 60 percent of the world population. This is the largest number of malnourished ever in history. In addition to food shortages, there are shortages of cropland and freshwater as well as fossil fuel—particularly oil—shortages. The oil shortage in the United States has prompted politicians and others to propose the use of corn and other food crops as sources of fuel, especially for ethanol production. As a result, nearly 9 billion gallons of ethanol is produced in the United States, using about 33 percent of US corn grain. This 9 billion gallons of ethanol represents only 1.3 percent of total oil consumption in the United States. But the numbers are telling: if all US corn were to be converted into ethanol, it would provide the nation with only 4 percent of total oil consumption. Given these facts, one asks, why is corn grain being converted into fuel while nearly 60 percent of the world population goes hungry? In particular why is US$6 to US$7 billion being spent to subsidize and encourage corn ethanol production? Unfortunately, the United States continues to produce corn ethanol because politicians find it politically useful, though the fuel is far from environmentally sustainable and a viable source for energy independence, as it uses up more energy to produce than it provides. Corn Ethanol In the United States, ethanol from corn constitutes 99 percent of all biofuels. To produce corn ethanol, corn is finely ground and approximately 15 liters of water is added to 2.7 kg of ground corn. After fermentation, to obtain a liter of 95 percent ethanol from the mixture of 10 percent ethanol and 90 percent water, 1 liter of ethanol must be extracted from approximately 10 liters of the ethanol/water mixture. To be mixed with gasoline, the 95 percent ethanol must be further processed to remove more water, requiring additional fossil energy inputs to achieve 99.5 percent pure ethanol. Thus, 22 pounds of corn grain is required to produce 1 gallon of ethanol. To fill the fuel tank of a SUV vehicle with corn ethanol requires a total of 660 pounds of corn or food. This is enough corn to feed two people in a developing country for an entire year. Furthermore, to produce corn ethanol, 46 percent more fossil energy is required to produce a liter of ethanol than than is yielded. Oil therefore must be imported to produce ethanol. As a result, the cost to produce 1 liter of corn ethanol is US$1.05 per liter or US$3.95 per gallon. The corn grain itself accounts for most of the economic and energy inputs to produce the ethanol. For example, it requires approximately 7,090 liters of fossil energy equivalents to produce 3,330 liters of ethanol. Then US President George W. Bush proposed harvesting cellulosic biomass and converting it into ethanol, suggesting that the United States could produce 36 billion gallons of ethanol through this method by 2020. However, while he proposed producing 23 gallons of ethanol per ton of cellulosic biomass, this figure was more than optimistic: our studies shows that it requires 3.3 gallons of oil to produce 1 gallon of ethanol from cellulosic biomass. What Bush also neglected to report was that the total amount of biomass, including 100 percent of all agricultural crops, forest growth, and grass growth each year, totals 2 billion tons (Table 1). Therefore, in order to harvest 1.6 billion tons of cellulosic biomass each year, producers would have to harvest 80 percent of total biomass each year, a clearly unsustainable and infeasible enterprise. Corn Ethanol Production Environmental Impacts The environmental impacts of producing corn ethanol are enormous. First, corn production causes more soil erosion than any other crop grown in the United States. Average soil loss per hectare of corn grown is 17 times greater than the soil formation rate—and it takes 500 years to replace 1 inch of eroded soil from cropland. Second, corn production uses more nitrogen fertilizer than any other crop grown. Nitrogen use is the prime cause of the “dead zone” in the Gulf of Mexico and also contributes to greenhouse gas accumulation and global warming. Approximately 155 kilograms per hectare each year (kg/ha/yr) of nitrogen is applied to corn fields. In addition, nearly 80 kg/ha/yr of phosphorus and 85 kg/ha/yr of potassium is applied per corn growing season. Corn production also uses more total insecticides and total herbicides than any other crop. Each hectare of corn receives nearly 3 kg/yr of insecticides and is treated with slightly more than 6 kg/yr of herbicides. More than 1,7000 gallons of water is required to produce 1 gallon of ethanol from corn. This includes the water required to produce the corn crop, plus the water used in processing the corn to create the ethanol. In addition to the energy used to grow corn for ethanol, there are other significant environmental costs. For example, for every gallon of ethanol produced, there are 12 gallons of sewage effluent that must be discarded. Most of the sewage waste is processed in city sewage processing plants, producing enormous quantities of carbon dioxide. This results from 7,090 liters of oil equivalents of fossil energy used in the production of ethanol per hectare. The fermentation process and the tilling of the soil also release large quantities of carbon dioxide into the atmosphere, while the conversion of cropland for biofuel production further contributes to the release of greenhouse gases. All this carbon dioxide release, of course, contributes to the global warming process, all while ethanol continues to be touted as a “clean fuel.” And using that “clean fuel” even contributes to air pollution. Burning ethanol in automobiles emits several pollutants such as peroxyacetyl nitrate (PAN), acetaldehyde, alkyates, and nitrous oxide. These have significant negative human health effects, as well as negative impacts on other organisms and ecosystems. Subsidies for Corn and Ethanol Corn grain was first subsidized in 1950 immediately after World War II. During the war, US farmers made a major effort to produce sufficient food for the United States, as well as for the United Kingdom and the Allies. After the war ended in 1945, there was a surplus of food being produced in the United States and prices of corn and other crops declined rapidly. As a result the US Congress and President passed legislation to subsidize corn, several other grains, peanuts, cotton, and sugar. These farm subsidies required that farmers raise only a single crop, like corn. This led farmers to sell off their livestock and end their production of a diversity of crops. Removing livestock from grain farms and placing them in feedlots constitued a major mistake as livestock manure could no longer be recycled effectively in crop production on the farm. This has resulted in a major pollution problem in the United States. More people are now exposed to livestock wastes than ever before. Earlier this year, the Center for Disease Control reported that there are 5,000 people, primarily children, die each year due to exposure to livestock wastes. Subsidization of corn crops has created further environmental difficulties. With corn production forced to be a continuous corn on corn production system, soil erosion increased dramatically from only 5 tons/ha/yr to 17 tons/ha/yr. The soil erosion problem costs the nation more than US$40 billion per year, and valuable cropland is degraded at the same time. Furthermore, weed and disease problems increased in corn production as farmers were forced to abandon growing corn in rotation with other crops. The most serious problem was the increase in the corn rootworm problem, leading to the high use of insectices. If farmers grew their corn in rotation with other crops, they could abandon the use of insecticides and also increase corn yields. Wheat, for instance, could be grown in alternation with corn, but the lower market value of wheat would lead to a reduction in economic benefit for farmers. Another problem associated with reducing crop rotations in corn production is that farmers are required to use more nitrogen fertilizer. As mentioned, corn uses more fertilizer today than any other crop grown, and the heavy use of nitrogen fertilizer in corn production results in nitrogen leaking from cornfields, the prime reason for the Dead Zone in the Gulf of Mexico. The result has been a serious reduction in fish and shrimp production. Corn ethanol subsidies are contributing further to the pollution and economic problems in the US. Currently US$6 to US$7 billion is spent each year subsidizing corn ethanol. This means that the subsidies for a gallon of ethanol are 60 times greater than the subsidies for a gallon of gasoline. The Consequences of Corn Ethanol More than 9 billion gallons of ethanol are being produced in the United States today. However, this ethanol represents only 1.3 percent of total oil consumption in the United States. Corn ethanol clearly does not make the United States energy independent. In fact, using 33 percent of all US corn for ethanol production has increased the price of meat, milk, and eggs by 80 percent for the US consumer. As many farmers switched from raising wheat and other grains to raising corn, the price of bread increased by 100 to 200 percent. The most serious concerns, however, have been the grain shortages in other nations, especially developing nations. As grain becomes scare, the rates of starvation and malnutrition soar. Jacques Diouf, Director General of the Food and Agriculture Organization of the United Nations, and Robert Zoellick, President of the World Bank, have both issued statements expressing their serious concerns about using food crops for biofuels, a practice that directly leads to starvation worldwide. With the detrimental effects of corn ethanol production and its devastating impact on consumers abroad and within the United States, it is critical for US policymakers to reconsider the necessity of subsidizing and encouraging the production of corn ethanol. As corn farmers benefit, the economy, the environment, and the world suffer.