Corn Ethanol: Another Bad Option For Energy

Michael Sojka
December 16, 2011

Submitted as coursework for PH240, Stanford University, Fall 2011

With rising fuel prices and Earth's rising temperature, people are looking anywhere to find an inexpensive way to fill up for their cars that will have minimal impact on the environment. With the constant turmoil in the Middle East and the demand for less dependence on foreign oil, fossil fuels are becoming less of an option. Also, the numerous reports of fossil fuels contributing to an increase in green house gasses are turning many countries away. Ethanol has emerged as a viable contender to replace fossil fuels. Ethanol is a type of alcohol based fuel that is made from the distillation of starch crops, mainly corn. To make ethanol, starch is separated from the other parts of the corn by adding a water molecule to each starch molecule. Then after fermentation, an alcohol and water mixture containing around 8% ethanol is produced. To create ethanol that is usable, up to three more distillations may be needed to be performed. Currently at gas stations all over the country, E10 and E85 ethanol fuel is being sold. E10 ethanol is a mixture of 10% ethanol with 90% gasoline while E85 is 85% ethanol mixed with 15% gasoline. America is the worlds number one producer of corn, producing over 40% of the worlds supply. [1] America is also a leader in the production of corn ethanol with over 3.4 billion gallons produced in 2004. [2] Ethanol, however, has some very serious drawbacks.

Drawbacks of Ethanol

In 2004, the United States mixed around 3.4 billion barrels of ethanol with gasoline to make fuel. This ethanol/gasoline mix amounted to around 2% of all gasoline sold. But how much energy is really attained from ethanol? Gasoline and ethanol do not have the same energy content. In terms of energy, 1.6 liters of ethanol equals 1 liter of gas. Since the ethanol/gasoline mixture contains less energy than pure gasoline, the 2% sold really only equates to about 1.3% of the total energy available. [2]

Ethanol is expensive to produce. The only reason that ethanol is a viable alternative to regular gasoline is because of the government's more than $3 billion in subsidies given to the producers and distributers of ethanol. Much of that money does not even reach the farmers who are the basis of both ethanol and food production in the US. When it comes down to it, farmers only get about $2.85 an acre from the subsidies. This is a very minimal profit. [3] With the national government looking for budget cuts, many of the ethanol subsidies could be cut. Without these subsidies, the price of ethanol will be too high to make it worth producing.

The price of most food will be affected by increased ethanol production. Fuel ethanol uses around 12 million acres of land for corn, about 15 % of the current acreage used for corn production. [4] The percentage is only going to go up with more focus being put on alternative fuels. Companies will be buying more corn to produce ethanol, the price of corn will most likely go up, consequently making the price of beef rise. 70% of corn is given to beef livestock as food. [3] With rising prices of corn due to increased ethanol production, the prices of beef and milk will be sure to rise. This will put added strain on the consumer who is already paying higher taxes for the government subsidies. Some farmers are even finding it cheaper to feed their animals human food, such as candy bars and trail mix, instead of the corn based feed. Reducing America's dependence on foreign oil will increase its dependence on other countries for food exports. [5]

One of the major issues of ethanol is its carbon footprint created by the conversion of natural ecosystems to farmland. The soil is a sponge for carbon. There is 2.7 times more carbon in the soil and plant biomass than in the atmosphere. When farmers expand their fields due to higher corn prices, a substantial amount of C02 is released into the atmosphere from either burning native flora (slash and burn) or the natural decomposition of tilled plants. This creates a carbon debt. The benefits of burning the ethanol will be less than the regular petroleum until the carbon debt is made up. The conversion of United States prairie to crop land creates a carbon debt that will take around 93 years to make up. [6] This means that for almost a century, burning ethanol will emit more greenhouse gases than burning gasoline. So if ethanol is going to be used as a viable alternative for gasoline, the effects of lowered carbon emission would not be felt for 93 years after the expansion of the corn fields.


In 2009, the annual consumption of gasoline in the United States was 150 billion gallons and it has increased since then. [1] If America was to substitute gasoline with corn ethanol, 240 billion gallons of ethanol would be needed due to its lower energy content. In 2008 whoever, the United States only produced 8.9 billion gallons of ethanol, well short of the 240 billion gallons needed to support America's energy consumption. [7] To meet these growing needs, the amount of land devoted to corn production would need to increase or corn currently used for food would need to be diverted to ethanol production. As previously stated, 15% of the acreage devoted to corn production in the US goes to ethanol. If Americans wanted to completely eliminate gasoline and run their cars on corn ethanol, they would need to use 27 times more acreage for corn production. That would mean using the equivalent acreage of twice the state of Texas just for corn production. Corn ethanol may stop America's dependence on foreign oil but is it really the best alternative? If companies start buying up large amounts of corn, they will only be taking corn out of the food supply. New technologies that make corn ethanol either cheaper or more energy rich are needed, or another fuel source needs to be explored. Corn ethanol is be being promoted by the government as the new clean source of energy that will decrease America's dependence on foreign oil. It might do that, but at the price of creating more carbon emissions and diverting corn away from food production. Is that really saving anything?

© Michael Sojka. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.


[1] M. B. McElroy, Energy: Perspectives, Problems, and Prospects (Oxford, 2010).

[2] A. E. Farrel et al., "Ethanol Can Contribute To Energy and Environmental Goals," Science 311, 506 (2006).

[3] M. H. Pimentel and D. Pimentel, Food, Energy, and Society (Taylor and Francis, 2008).

[4] J. R. Wilson and G. Burgh, Energizing Our Future: Rational Choices for the 21st Century, (Wiley, 2008).

[5] D.B. Botkin, Powering the Future (FT Press, 2010).

[6] J. Farigone et al., "Land Clearing and the Biofuel Carbon Debt," Science 319, 1235 (2008).

[7] "The Impact of Ethanol Use on Food Prices and Greenhouse-Gas Emissions," U.S. Congressional Budget Office, April 2009.