Symposium addresses how to grow better feedstocks to fuel the world
Illinois crop scientist D.K. Lee compares notes at the feedstock symposium with graduate assistants Eric Anderson (left) and Santanu Thapa (right).
As fields turn the color of spun honey, thoughts return to the land that provides food, and also fuel, for the world. The Breadbasket may soon become our nation’s “Fuel Tank” as more acres and research dollars are devoted to non-food bioenergy crops.
At the ninth Bioenergy Feedstocks Symposium, a two-day August conference in Champaign, IL, leaders from many disciplines—including seven Energy Biosciences Institute faculty members from the University of Illinois—discussed the challenges involved in producing safe and productive non-food feedstock to meet fuel needs. Almost 100 academic and industry representatives from 10 states attended the meeting. Some of the most discussed aspects of feedstock development included:
Biomass getting bugged
Initially, it was believed that perennial grasses used as potential feedstocks had few pests, said Michael Gray, Professor of Entomology, Department of Crop Sciences. But recent research says otherwise. The potential culprits include some species of aphids, fall armyworms, southwestern corn borers, other species of stalk borers, and leafhoppers that can vector certain species of viruses. Gray said geographic location, size and management of feedstock fields are factors that influence the intensity of pest infestations and the potential for pests to cause biomass reductions.
As recent journal evidence shows, Miscanthus and switchgrass are not free of plant pathogens, said Carl Bradley, Associate Professor of Crop Sciences. In Miscanthus, researchers found, among other types, Curvularia (fungus), Fusarium (blight), and Pithomyces. Switchgrass pathogens included Tilletia (smut), Puccinia (rust), and anthracnose—which reduced biomass by 40 percent. Researchers also discovered a new virus called switchgrass marafivirus (SwMV) using Sequence Independent Amplification, a new method developed to find viruses.
New feedstock: friend or foe?
Arundo donax—a giant reed that can grow 10 centimeters a day and easily propagate—was recently approved as a renewable fuel pathway, said EBI postdoctoral researcher Lauren Quinn.
The Environmental Protection Agency’s risk mitigation plan requires stakeholders to prove that key management practices will prevent the plant from becoming invasive. To avoid mistakes made in the past through intentional introductions of non-native species, they will have to learn to think like invasive plant ecologists.
“As other non-native bioenergy feedstocks are introduced, care must be taken to avoid escape from cultivation and invasion in natural landscapes,” she said. “All non-native feedstocks should be evaluated for invasive potential prior to introduction.”
Dollars and (emissions) sense
Research shows that not all cellulosic biofuels are created equal, yet the Renewable Fuel Standard treats them all the same, said Madhu Khanna, a Professor of Agricultural Economics. To qualify as a biofuel, a cellulosic feedstock must reduce greenhouse gas (GHG) intensity by 60 percent relative to gasoline. Biofuels from energy grasses can be net sinks for carbon as compared to those from crop residues that generate lower greenhouse gas emissions but could be more expensive. “We have to think about alternative policies that would reward producers for growing feedstock that can reduce GHG intensity by more than 60 percent but may be more expensive to produce,” she said.
Setting a standard for sustainability
As sustainability debates continue, standards will no doubt play a key role in the future production of biofuels, said Jody Endres, an Assistant Professor of Law. A final report, three years in the making by the Council on Sustainable Biomass Production, provides the Natural Resources Conservation Service with guidelines for the development of sustainability standards, which includes a certification process and resources to help farmers become certified.
Enough to go around?
The false assumption that the maximum productivity of land is equal to what the natural ecosystem would have produced has led many to believe that there may not be enough biofuels (or food) to go around. But models are only as good as their assumptions, said Evan DeLucia, Professor of Plant Biology. He believes global productivity has been underestimated and is holding out hope that there will be enough, and maybe even some to spare, to allow careful management of both food and fuel crops together.