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The Rush To Corn-Based Ethanol: Not All Biofuels are Created Equal

While global demand for fossil fuels grows, gasoline prices remain volatile. Add in concerns about climate change and alternatives to oil-based fuels look increasingly attractive. However, corn-based ethanol, the most prominent biofuel in the United States, will not answer any of these issues.

The ability of corn-based ethanol to reduce U.S. dependency on foreign oil is limited; even dedicating the entire U.S. corn crop to ethanol would displace only a small share of gasoline demand.  Plus ethanol does little to nothing to fight climate change. Large-scale corn production requires farm equipment that runs on fossil fuels. Coal-powered ethanol refineries can lead to higher greenhouse gas emissions than the fossil fuel ethanol is intended to replace.

Is Ethanol the Solution to Energy Independence?

Corn growers and ethanol producers talk enthusiastically about replacing the oil fields of the Middle East with the corn fields of the Midwest. But the true potential for biofuels to replace oil is not as sparkling as the rhetoric.

The most favorable estimates, which include still-developing cellulosic feedstocks, point out that fuel made from biomass can replace only a fourth to a third of transport-related oil consumption.  The Congressional Research Service has estimated that even if 100 percent of the U.S. corn harvest were dedicated to ethanol, it would displace less than 15 percent of national gasoline use.

When blended with gasoline, ethanol  helps to burn the fuel more effectively and produce less pollution. Ethanol’s role as an oxygenate     became prominent in the mid-2000s when many states began banning the more widely used oxygenate MTBE. MTBE was found to be a drinking water contaminant requiring expensive cleanup efforts. Ethanol became touted as a safe alternative resulting in a big push to blend it with gasoline. This does seem like a redeeming quality, but is not enough of a reason to expand corn-ethanol use.

Ethanol and Factory Farming

Ethanol production is often tied to factory farming  of livestock. Ethanol plants produce byproducts that can be used as feed for animals, in turn, factory farms can sell animal manure as fuel for ethanol plants. These synergies may increase efficiency for both the ethanol and the livestock industries, but have the potential to seriously affect environmental quality, human health, and communities throughout entire regions.

The increasing concentration and industrialization of the U.S. agricultural sector has resulted in factory farms where animals are raised by the thousands, often in crowded conditions.  Huge amounts of manure accumulate in open lagoons that can cause air and water pollution. The waste can contaminate water bodies with E. coli and other bacteria.

Livestock production and ethanol production are both water intensive. Siting both types of facilities in the same area could greatly reduce water availability, particularly in Midwestern regions that already suffer from water scarcity.

Corn and Pollution

Intensive corn monoculture  has serious environmental effects that are exacerbated by the ethanol boom. If fertilizers used to grow corn runoff the field into water bodies, it can cause overgrowth of algae in rivers and lakes and destroy habitats of certain marine species. Farm runoff from the mid-western states has resulted in the formation of a “dead zone” that averages 6,700 square miles within the Gulf of Mexico.

Widespread use of herbicides leads to the contamination of water and soil. In the spring time, when corn farmers apply the largest quantities of herbicides to their fields, rains can wash these chemicals into the drinking water of 11.7 million people throughout the central United States.

Going Forward

Corn ethanol should not be seen as a solution to meeting all of our fueling needs.  Instead of this perceived silver bullet, we need a toolbox of measures that will reduce the huge amount of oil we use every day to move people and goods around. Ethanol from corn is not the solution to greenhouse gas emissions, high oil prices, or dependence on foreign oil.

Since we released Rush to Ethanol in 2007, policy measures in the U. S. have evolved. Ethanol mandates require greater amounts of the fuel to be blended with gasoline. However, subsidies doled out per gallon of ethanol expired at the end of 2011. Policymakers are getting wise to the fact that ethanol is not a panacea, but powerful interests in corn states keep the rush to corn-based ethanol going.


  • Monoculture
  • Factory Farm (Industrial Farm / Industrial Agriculture)
  • Oxygenate