
Sorghum being harvested. The annual crop produces seed heads used as biofuels. Photo courtesy of CABBI – University of Illinois.
A University of Idaho researcher has been awarded more than $750,000 to study biofuels.

Tara Hudiburg
Tara Hudiburg, assistant professor with the University of Idaho’s College of Natural Resources, was awarded the grant to study biofuel sustainability. She is a co-principal investigator and will lead the biogeochemical modeling as part of the sustainability initiative of the project.
Biogeochemical modeling includes assessment of greenhouse gases, improving predictions of future crop yields, and assessing impacts on soil health, biodiversity and water quality.
The grant, awarded by the Department of Energy, is part of a $115 million project intended to create a new generation of sustainable, cost-effective bioproducts and bioenergy. The biofuels research team consists of 60 people in 17 institutions, of which the University of Idaho is the westernmost.
The use of corn for ethanol is controversial, in part because corn could otherwise be used to feed people. Hudiburg said the researchers will study mostly non-food biofuel crops such as switchgrass, miscanthus, and sorghum, she said. “Switchgrass is a native, like prairie grass,” she said. “You’d recognize miscanthus – it’s a horticultural bunchy grass that gets really tall.” Both are hardy and don’t require much water or nitrogen, she said. In addition, they’re both perennials, meaning they don’t have to be sowed every year and the soil doesn’t need to be tilled. “You plant them, you mow it like grass, and the root system stays intact,” she explained. “The soil stays healthy, the carbon stays in the soil, and the carbon budget works out in a much more positive way.”
The grain heads of the sorghum plant, an annual, produce oils that are useful for high-density fuels; the two grasses produce fuels from cellulose, she said.
All three crops are unlikely to replace food crops, Hudiburg said. “Part of the modeling we do is to keep food constant in terms of land use,” she said. “It’s not about replacing food, but about replacing non-food corn. We’re seeking out marginal lands, land that’s not going to be converted for crops.”
Hudiburg’s group will focus on the economic and environmental components of biofuels, she said. “There’s no point in pursuing any of this if it’s not” environmentally better or more economically sustainable than fossil fuels, she said. “We’re making sure that it’s going in a direction that’s sustainable for the planet.” As part of her work, she runs scenarios for factors such as drought and climate change to calculate projected yields.

Ralph Cavalieri
“When you calculate the energy efficiency and carbon impact of alternative fuels, you go back to the crop and look at the inputs required to produce the crops – even so much as how much diesel fuel you end up using,” said Ralph Cavalieri, emeritus professor in biological systems engineering and director of the Northwest Advanced Renewables Alliance for Washington State University. “Perennials are great. That’s why switchgrass is so popular. It grows really tall, really fast,” allowing researchers to harvest a seven- to eight-foot stalk of it every year, he said.
Idaho’s agricultural industry isn’t likely to benefit from the biofuels research, Hudiburg said.
“It really works best in places without hot, dry summers” because of the need for irrigation, she said, though she added that part of the research involves working on the drought-tolerance part of the genome and water use efficiency.
Most likely to benefit from the research is the University of Idaho itself, Hudiburg said. “From a university point of view, it puts us on the map with other institutions,” she said. In addition, she can send graduate students to the participating universities, she said.
Idaho has had various biofuel programs before, said John Chatburn, administrator for the Idaho Governor’s Office of Energy and Mineral Resources. While the state doesn’t have any particular programs in biofuels, it keeps track of developments and proposed developments in the commercial sector, he said.
The story was edited on June 1 to reflect an updated Department of Energy grant figure.