In the quest for economically viable cellulosic ethanol, switchgrass has garnered attention as a hardy, low-cost energy crop. While cellulosic ethanol is still agreed to produce emissions benefits over corn-based ethanol, and while the adaptability of switchgrass to different growing conditions remains one of its virtues, some farmers who have grown switchgrass say the crop's cost of production can be considerably more than corn.
While the Energy Department has specified the target production cost for corn at $35 per ton, farmers in Iowa have found switchgrass to cost around $60 a ton to produce, according to an article in the Des Moines Register. Iowa State University economist Mike Duffy puts the price tag at $50 a ton.
Regardless, Mark Downing, a bioenergy market analyst with the Energy Department, says in the article that "There's no $35-a-ton switchgrass."
"That's going to be really tough, to get a farmer to get out of corn and produce switchgrass," he says. Some of this has to do with Iowa's high cost of land, however. An area with land less ideal for high-priced commodities such as corn or soybeans could be more likely to draw switchgrass growers.
Cellulosic ethanol production, whether from switchgrass, cornstalks, or wheat straw, results in considerably lower greenhouse gas emissions than corn-based ethanol production - 90%, by the estimation of a study by the University of California at Berkeley.
The trick remains finding an economically viable process. In the U.S., there are currently no plans for large-scale commercial plants that could develop the technology to make ethanol from switchgrass.