Switchgrass, a tall-growing prairie grass native to Oklahoma, might in the not too distant future help ease the United States' dependence on foreign oil. When the day comes, and a number of researchers and policy wonks in the state are working toward it, it could benefit national security, the environment and Oklahoma farmers in the bargain.

Biofuels have been around for years, usually taking the form of corn-derived ethanol blended with gasoline. But national security concerns prompted by the Sept. 11, 2001, terrorist attacks and recent instability in the Middle East have given new urgency to the development of a renewable, domestic energy source.

Biomass, which means all plant and plant-derived materials including animal manure, is the only source of liquid transportation fuel currently available. It provides about 3 percent of total U.S. energy consumption.

The Biomass Research and Development Technical Advisory Committee, a panel established by Congress, has set a goal of replacing 30 percent of the nation's present petroleum consumption with ethanol by 2030.

Ethanol produced from corn accounted for about 2 percent, or four billion gallons, of the U.S. transportation fuel market last year. About 11 percent of the country's corn harvest went to that purpose. Given that 60 billion gallons of ethanol will be needed to meet the 30-percent-by-2030 target, corn alone won't be enough.

A 2005 report by a group of experts empaneled by the U.S. Department of Agriculture estimated that 1 billion dry tons of biomass annually will be needed to meet the 2030 goal. The group found that more than enough biomass – 1.3 billion dry tons – is potentially available, if all sources are used. That would include such diverse things as trees, paper and pulp residues; corn stover and wheat stalks (not just the grain); brush cleared in fire-reduction efforts, and animal manure.

That's where switchgrass comes in, according to Oklahoma Secretary of Energy David Fleischaker and Dr. Joe Bouton, director and professor of forage improvement at the Ardmore-based Samuel Roberts Noble Foundation.

Switchgrass is attractive as a biomass feedstock for several reasons. It is a perennial, which means it doesn't need replanting and tilling of the soil every year. It is drought-resistant and pest-resistant. It grows in a wide variety of climates and in less productive cropland.

Switchgrass is environmentally friendly. It doesn't require the nutrient loading (fertilization) that corn needs and in fact it transfers nutrients back into the soil before harvesting. It is planted as a ground cover for erosion control, in contrast to row crops like corn which can cause erosion.

Burning ethanol made from plants, like burning fossil fuels, produces the greenhouse gas, carbon dioxide. However, unlike petroleum, the plants used to produce ethanol consume carbon dioxide from the air as they grow, so the net impact on air quality is less.

Using switchgrass to make ethanol avoids the ethical question that is sometimes raised about using a human food crop for transportation fuel while people around the globe are starving.

Perhaps most important, however, switchgrass produces nearly five times more energy per unit than does corn.

Researchers at the Noble Foundation, Oklahoma State University and the University of Oklahoma, among others, are working to develop a switchgrass variety that is ideal for use as biomass feedstock, and to work out which is the most practical of two competing technologies for converting it to ethanol.

Already there are several small biofuel refineries operating in Oklahoma, including biodiesel operations in Durant and Chelsea that use soybeans or canola. A proposed biodiesel refinery in Guymon, heart of the state's cattle and pig operations, would use animal renderings. A proposed large-scale biofuel refinery in Enid would be capable of producing 50 million to 60 million gallons of ethanol a year from corn.

Making ethanol from switchgrass on a commercial basis will require building or modifying compatible refineries. Oklahoma's energy secretary, Fleischaker, says that could happen in as little as five years.

Switchgrass won't supplant corn as a biomass feedstock. It and a wide variety of other plant-derived materials will supplement corn. Switchgrass has the potential to help lessen U.S. dependence on foreign oil as well as to help make sure that some of the $320 billion a year that the U.S. transfers to foreign countries for oil will remain here in Oklahoma, with Oklahoma farmers. Sounds like a deal.

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This article appeared in the Tulsa World, www.tulsaworld.com, on September 24, 2006.