More Efficient Crop for Biofuel Production Proven

The race to find viable sources for biofuels took a leap forward today, according to the research published in the early online edition of the Proceedings of the National Academy of Science from the Department of Agriculture's research facility located at the University of Nebraska, Lincoln.

To date, ethanol-based alternative fuels have relied on corn for production, with massive inputs of fertilizers and pesticides, and time and energy spent in annual planting. That, and corn is used in a vast array of food products, and as livestock feed, making the diversion of corn an economically tough call for farmers and agricultural policy-makers.

That could all change, with the finding that switchgrass (Panicum virgatum), a perennial plant that will grow well on marginal land, can produce net energy more than five times of that being produced using corn. That, with naturally occurring switchgrass, and no effort to date to breed the species for traits that could make it even more productive as the feedstock for alcohol production.

Switchgrass, also called tall panic grass, Wobsqua grass, lowland switchgrass, blackbent, tall prairiegrass, wild redtop, and thatchgrass, is native to the Midwestern plains, and one of the dominant species found in the once-ubiquitous prairies. It grows from 1.8 to 2.2 meters in height (5.5 to 7 feet), and is easily established in a wide range of growing conditions. Tests were conducted using 10 acre stands planted from northern North Dakota to southern Nebraska over a five year period.

Part of the impact comes from switchgrass having a higher cellulose content than corn, permitting more of its bulk to be liquefied and the sugars released then a comparable mass of corn, and part of the mass being able to be used as fuel for small electrical turbines and boilers, allowing the ethanol plant to be self-fueling.

Dr. Thomas Voigt, a professor in the University of Illinois Department of Natural Resources and Environmental Sciences studying different plants for biofuels, agreed in a telephone interview that the biomass effect is probably the most difference between switchgrass and other grasses, and corn. According to Dr. Voigt, for every unit of petrochemicals put into corn, you only get 1.3 units of ethanol, while sources like sugar cane produce 8. His research Miscanthus x giganteus shows that that species also bears promise for biofuel production, based on which crop you grow and where.

With the advent of new technologies for even more efficient conversion of plant materials into alcohol, the study said the United States is on the cusp of turning roughly 30% of its energy needs over to alcohol from petroleum.