Recently ethanol has been getting a lot of heat. In March, Time Magazine ran, The Trouble with Biofuels, an article that suggest that ethanol isn't a cure-all substitute for petroleum, and may even exacerbate global warming. Time isn't the only source skeptical of the ethanol boom. A slew of journalists and experts are saying the same thing: the commercial production of ethanol is a factor in rising food costs, deforestation and increased hunger worldwide. Perhaps the most ironic pitfall of mass ethanol production is that right now, corn ethanol is appears to be leaving a bigger carbon footprint then oil. Once hailed as a miracle substitute for petroleum, ethanol's manufacturing may prove to be more trouble then it's worth.
The Trouble With Corn
Corn, soybean and sugar cane are among the most popular ethanol crops. To make ethanol, sugar is extracted from these plants and converted into alcohol (ethanol). Corn is a choice crop because of its high sugar content as is sugar cane. To meet the increased demand for ethanol—both the US and the EU have 'clean fuel mandates—farmers are clear cutting virgin land to grow ethanol crops. Increased demand has also driven up the price of food staples like corn, soy and sugar.
Even when you ignore the ethical question that making fuel from food poses, from a strictly practical standpoint, growing corn and soy to make ethanol on a large scale just isn't practical. Both corn and soybean require extensive amounts of energy and water to farm and refine. By the time they have been harvested and processed, the resources expended through production and transportation are greater then the energy yielded from the ethanol produced.
Government and Market Forces are Fueling the Corn Ethanol Production
A market demand for green fuel is driving the ethanol production. People want to drive 'green' cars, and businesses are trying to reduce their carbon footprint as well with alternative energy. The federal government has caught onto the trend by mandating alternative energy production, which in turn has boosted corn based ethanol manufacturing. In 2006, thanks in part to strong lobbyist; corn ethanol subsidies totaled 7 billion dollars. This year corn prices peaked, causing poor people in Mexico and India to protests because they can no longer afford food.
Switch Grass May be the Solution
Switchgrass, a plant native to the American prairie, may be the answer to the ethanol dilemma. Switch grass grows quickly and is an extremely adaptable plant, able to survive in most climates. The resourceful perennial digs deep into the soil to utilize any water around. switchgrass requires significantly less energy to farm, when compared to corn and soybeans.
The plant grows wild and utilizes solar energy to produce large amounts cellulose. To make ethanol, cellulose is converted into sugar, which in turn is converted into alcohol (ethanol). Though Switchgrass is easier to farm and doesn't affect food costs, as of now, converting it into ethanol is more expensive then corn. The enzyme required to breakdown corn into sugar is cheap, at around 3 per gallon. The enzyme required to break down cellulose ranges anywhere from 30 to 50 cents per gallon. Though switchgrass requires a more complicated process to refine, it is worth the investment. According to an article in Scientific American Magazine, switchgrass produces 540% more energy then the amount consumed growing it. Scientists are working hard to refine cellulose ethanol production, with corporate and government dollars behind them. The US Department of Energy is largely funding six new cellulose bio-refineries, estimated to cost 1.2 billion dollars. Two weeks ago Du Pont and biotech firm Danisco’s Genencor division committed 140 million dollars, in a joint venture to develop and sale cellulose ethanol technology. "There is nothing in the last several decades that has generated such private sector enthusiasm and investment,” said Keith Collins, the Agriculture Department’s chief economist.
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Photo courtesy of USDA-ARS
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