Turning Switchgrass into Low Cost Ethanol

"There are several impediments to the process of converting switchgrass to ethanol that would make unaltered switchgrass commercially unprofitable. We are working with professors at Brown University, for instance, to create better enzymes that will degrade cellulose into sugars for a more efficient conversion to ethanol," said Kausch.

An expert on "gene confinement," Kausch has spent 20 years genetically modifying a variety of turf grasses, rice and corn, and is now working to create a switchgrass that does not flower or reproduce -- ensuring that the genetically modified organisms do not escape into the environment and affect wild switchgrass.

"That's a key concern with using corn for ethanol because some of the genes being engineered into corn to make it a better source of ethanol aren't genes we want in the food chain. And without confinement, such as plant sterility, those genes could find their way into the corn that we eat," said Kausch, who launched Project Golden Switchgrass at URI.

He noted that sterile plants which do not use their energy to produce flowers will produce more biomass in the form of leaves and plant material and, ultimately, create more ethanol.

Unlike corn, which is currently used for ethanol production, switchgrass can be grown on marginal soils, is useful as wildlife habitat, and requires little use of fertilizers, insecticides or irrigation. In addition, switchgrass is a perennial plant and doesn't require replanting year after year.

"Switchgrass is a native plant of the tall grass prairies. It grows 12 feet tall in one season and produces 10 tons of plant material an acre, more biomass per year than most other plants," said Kausch. "I'm confident my lab can make it produce 20 tons an acre using the tools and personnel we have right now."

Along with genetically engineering switchgrass that is both sterile and resistant to herbicides, Kausch has a long list of other traits he hopes to improve as well, including drought tolerance, salt tolerance and cold tolerance.

Despite having studied corn for many years, Kausch believes it may not be best choice for ethanol production.

"Some critics argue that there is not enough good quality arable land available to grow the amount of corn required for biofuels, and all that we produce now is used for food instead of fuel," he said. "Corn is also very expensive to grow compared to switchgrass."

Since a majority of the carbon dioxide emissions that cause global warming come from transportation sources, Kausch believes that switching from gasoline to 100 percent ethanol is an important step toward halting climate change.

"It won't entirely solve the problem, but it sure will help," said Kausch. "And the reduced CO2 that comes from your tailpipe is then absorbed by the plants that are then turned into ethanol again, so it becomes a natural cycle."

Kausch expects to have test plots of the genetically modified switchgrass plants on the URI campus within two years, and hopes the first varieties will be in commercial production by 2011.

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