Is ethanol really energy solution?

July 02, 2006|By HAROLD KUNG

More and more leaders outside of environmental circles are looking to the nation's cornfields these days to solve the United States' energy problems.

The growing interest in ethanol, a clean, corn-based renewable resource, has paralleled the escalating price of gas and the urgent need to break the country's dependence on crude oil.

Recently, the Big Three automobile manufacturers appealed to Congress for incentives to increase the number of gas stations that offer blends of ethanol. They also endorsed a plan to meet 25 percent of the nation's transportation fuel needs with corn ethanol by 2025.

That certainly is a laudable goal. But what would it take to convert 25 percent of transportation fuel use to ethanol? The enormity of the challenge is staggering.

The United States would have to dedicate 260 million acres to corn production. For comparison, the total land area of Illinois is 37 million acres.

Keep in mind that ethanol generates less energy than gasoline - one gallon is equivalent to two-thirds of a gallon of gas - and its production consumes energy.

In 2004, for example, the United States imported 4.9 billion barrels of crude oil, and American motorists used 139 billion gallons of gasoline, not counting diesel fuel consumption. Replacing a quarter of gasoline consumption would equal 35 billion gallons. Because ethanol generates less energy than gasoline, 52 billion gallons of ethanol would seem to be required.

But even that estimate is inaccurate because of the energy consumed in the production of ethanol. Experts estimate that to make one gallon of ethanol for motorists, the production process requires energy equivalent to burning at least another 0.62 gallons of ethanol. That means that at least 84 billion gallons of ethanol per year would be needed in order to supply 25 percent of motor fuel (based on 2004 numbers). This estimate represents a 25-fold increase in the production of ethanol in America.

Such a transformation of land for that scale of production would be so expensive and extensive that, in the short run, changing to ethanol would disrupt the regional economy and cost more than continuing to rely on imported fossil fuels.

But in the long run, a huge investment in ethanol production could prove successful. Presumably, most of the capital invested in new farmland and the expenses in acquiring the ethanol would stay within the domestic economy instead of being exported. Imported oil would decline by 20 percent, which should enhance the country's energy security and reduce international conflict.

Combined with solar, wind, hydro and possibly nuclear sources of energy, ethanol could be part of the solution for long-term energy sustainability. It could be a solution in which there would be no reliance on imported energy source, no net consumption of nonrenewable resources and no net emission of global warming carbon dioxide into the atmosphere.

In other words, the Big Three and the government cannot expect that new ethanol technology alone, with all its unwieldiness, will cut the country's dependence on crude oil in the next couple of decades. Significant improvement of the U.S. energy situation will require that companies change their business models, consumers change energy consumption behavior and the government accept its responsibility to lead the country to sustainability.

In the short run, industry needs to produce what customers want while enhancing energy efficiency. The government should model the Corporate Average Fuel Economy (CAFE) program after successful emission-trading formulas. CAFE provides incentives for manufacturers that produce gasoline vehicles that are also ethanol-ready.

Those market-based trading formulas allow utilities to either reduce emissions or buy credits from other companies, letting them defer investments in their own plants. The government could induce consumer behavior changes with similarly strong measures.

If we truly are serious about addressing our high energy consumption - and also saving the planet - a variety of fuel alternatives must be considered. And now.

Harold Kung is professor of chemical and biological engineering at the McCormick School of Engineering and Applied Science at Northwestern University. His e-mail is hkung@northwestern.edu.

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