Is Ethanol The Answer?

There is a growing controversy over the use of ethanol as a fuel additive in the U.S. On the one hand, ethanol is renewable, can be produced domestically, and burns cleaner than gas. On the other hand, ethanol production requires a lot of energy (often from fossil fuels), uses a lot of water, and has a ripple effect that drives up food prices.

Ethanol is grain alcohol. It is made from the fermentation of sugar and is the same type of alcohol found in alcoholic beverages. It can also be used as fuel. Indeed, Henry Ford designed the first mass-produced automobile, the Model T, to run on pure ethanol.

Ethanol is derived from plants through a fairly straightforward process. In the U.S. corn is the most widely used ingredient. It is first ground into a fine powder, mixed with water, and then heated.

An enzyme is then added to convert the mixture into sugars before yeast is added to ferment it. The resulting liquid, called "beer," is about 10% alcohol. A distillation process then separates the alcohol from the rest of the mixture before the remaining water is removed. The result is essentially pure alcohol. A small amount of gas is added to render the liquid undrinkable. Then the fuel can be used by itself or as a supplement to gasoline to power cars.

The Benefits of Ethanol

Ethanol burns cleaner than gasoline and thus causes less air pollution. It is increasingly be used as a replacement for the gasoline additive called MTBE (for methyl tertiary-butyl ether) which is used to oxygenate gasoline, but can contaminate drinking water. Ethanol is biodegradable and doesn't directly harm the environment.

Ethanol can be produced domestically, lessening our reliance on imported fuels. Unlike petroleum, it is also renewable as it is made from plant sources.

The Drawbacks

Ethanol requires a substantial amount of energy to be produced. Many contend that ethanol production (including the use natural gas based fertilizers, farm equipment, transformation from corn or other materials, and transportation as energy inputs) uses so much energy that it actually leads to a net energy loss. Furthermore, ethanol production calls for excessive quantities of water both in the growing of corn and in the fermentation process.

Government subsidies for corn growers and ethanol production also cause problems. The boom in corn production for ethanol is leading to excessive fertilized use. Each year, spring runoff washes nitrogen-rich fertilizers from farms in the Mississippi River basin and carries them into the river and the streams that feed it. The nitrogen eventually empties out of the mouth of the Mississippi and into the Gulf of Mexico, where tiny phytoplankton feed off of it and spread into an enormous bloom, thus worsening the so-called "dead-zone" in the Gulf of Mexico.

Additionally, these subsidies have caused the price of corn to soar producing a ripple effect that has driven and continues to drive up the cost of food in general worldwide.

All in all, it would seem that the drawbacks of using corn ethanol for fuel outweigh the benefits.

For further reading on ethanol see:

Ethanol's Growing List of Enemies
Ethanol: Myths and Realities
For Ethanol, The Future is Now (National Public Radio)