Imagine a place where farmers could grow a specific type of crop that could be processed to produce a product that people need to drive their cars.

That place is Tennessee. That crop is switchgrass. That product is ethanol.

On October 23, Dr. Kelly Tiller, as associate professor of agricultural economics, delivered a presentation, "The Economics of Switchgrass to Ethanol," at the UT Science Forum.

The Southeast, which lacks the necessary sources for strong solar, geothermal or wind energy, has been called the "Saudi Arabia of Swithgrass." One acre of switchgrass produces 1,000 gallons of ethanol. Kelly Tiller, associate professor of agricultural economicsOne acre of switchgrass produces 1,000 gallons of ethanol, says Tiller.

"It [switchgrass] grows fast, capturing lots of solar energy and turning it into lots of chemical energy- cellulose-that can be liquefied, gasified, or burned directly," according to an Oak Ridge National Laboratory Web site source. "It also reaches deep into the soil for water, and uses the water it finds very efficiently."

Though switchgrass has its advantages, Tiller did not hesitate to point out the disadvantages.

The challenge lies in persuading farmers to grow switchgrass in the current market where there's almost no demand for the crop.

As part of the $70.5 million state commitment and the collaborative efforts of DuPont Danisco Ethanol, LLC, the University of Tennessee Research Foundation and Genera Energy, LLC, farmers are provided switchgrass seed, technical expertise and a $450 incentive per year for three years to grow and produce switchgrass.

In 2008, 723 acres of switchgrass were contracted on 16 farms.

"Seventy-five percent of our farmers in 2008 asked for additional acreage in 2009," said Tiller, president and CEO of Genera Energy. "That's a fairly strong indication of success."

More than half of the state commitment, $40.7 million to be exact will go to constructing the biorefinery, where the switchgrass to ethanol conversion takes place.

In her presentation, Dr. Tiller explained the process. First, the switchgrass, wood chips and other biomass arrive at the biorefinery. Then, steam and acid separate shredded biomass into cellulose, hemicelluloses (less complex than cellulose) and lignin ("liquid wood"). The cellulose and hemicelluloses are broken down into sugars, while the lingin is removed for other products. After the yeast turns the sugars into alcohol, distillation removes water and increases the alcohol's potency as a fuel. Finally, the cellulosic ethanol ("grassoline") is transported to consumer outlets.

According to the Genera Energy Web site, collaborators expect to produce ethanol from the biorefinery by the end of 2009.

The economics of switchgrass and ethanol can perhaps best be summarized by the following statistic that Tiller gave the audience - for every dollar spent at the pump for gasoline, 80 percent goes out of the state. For every dollar spent at the pump for cellulosic ethanol, zero percent goes out of the state.