CHAMPAIGN, Ill. — In the largest field trial of its kind in the United States, researchers have determined that the giant perennial grass Miscanthus x giganteus outperforms current biofuels sources – by a lot. Using Miscanthus as a feedstock for ethanol production in the U.S. could significantly reduce the acreage dedicated to biofuels while meeting government biofuels production goals, the researchers report.
Using corn or switchgrass to produce enough ethanol to offset 20 percent of gasoline use – a current White House goal – would take 25 percent of current U.S. cropland out of food production, the researchers report. Getting the same amount of ethanol from Miscanthus would require only 9.3 percent of current agricultural acreage. (View a narrated slideshow about Miscanthus research.)
“What we’ve found with Miscanthus is that the amount of biomass generated each year would allow us to produce about 2 1/2 times the amount of ethanol we can produce per acre of corn,” said crop sciences professor Stephen P. Long, who led the study.
“One reason why Miscanthus yields more biomass than corn is that it produces green leaves about six weeks earlier in the growing season,” Long said. Miscanthus also stays green until late October in Illinois, while corn leaves wither at the end of August, he said.
The growing season for switchgrass is comparable to that of Miscanthus, but it is not nearly as efficient at converting sunlight to biomass as Miscanthus, Frank Dohleman, a graduate student and co-author on the study, found.