The report also raises questions about the environmental impact of cellulosic biofuels. Tyner said it's uncertain whether some cellulosic fuels would lower greenhouse gases because of the emissions that would be released when new land is cultivated.

Tyner and co-chair Ingrid C. Burke, director of the Haub School and Ruckelshaus Institute of Environmental and Natural Resources at the University of Wyoming, presented their findings Oct. 3 to congressional staffers, agency representatives and the executive branch, and at the National Press Club in Washington, D.C., on Oct. 4.

"There are conditions in which you could see us meeting the Renewable Fuel Standard for cellulosic biofuels, but they require major leaps in technology, substantial increases in oil prices and/or very large subsidies," Tyner said.

The committee also included members from the Oak Ridge National Laboratory, Michigan Technological University, the University of Minnesota, the University of California Davis, ProTech Consultants, Iowa State University, Synthetic Genomics, the University of Iowa, Michigan State University, Kansas State University, Ohio State University and the University of Alaska Fairbanks.

The U.S. Department of the Treasury, Department of Agriculture, Department of Energy and the U.S. Environmental Protection Agency sponsored the study. The data was peer-reviewed before distribution.