Hybrid poplar may hold potential as source for ethanol
Technological issues must be solved
By Gary Gunderson
BENSON, Minn. -- Hybrid poplar and other trees could eventually produce ethanol, but technological problems will have to be overcome, says the quality manager of the Chippewa Valley Ethanol Co.
Trees contain the sugars needed to produce ethanol, but the sugars are bound in the tree's cells by lignin, said Kelly Davis during a presentation at the Minnesota Agro-Forestry Cooperative's annual meeting. A process will have to be developed that breaks down the lignin without destroying the sugar.
"Can we make ethanol from trees? No problem, if we could get rid of the lignin," Davis said. "There are technological hurdles."
The Minnesota Agro-Forestry Cooperative consists of landowners who have planted hybrid poplar, usually on former fields, said Dennis Gibson, cooperative president. The trees mature after 10 to 15 years and members want to explore all possible uses for their crop.
Most likely, hybrid poplars will be used for paper and orientated strand board unless a workable and cost-efficient ethanol production method is developed soon, said Keith Jacobson, a utilization marketing program director for the Minnesota Department of Natural Resources. The cooperative started in 1996, and many of the members' trees will be ready to cut within five to 10 years.
Would-be ethanol producers can't use processes developed for making paper and methanol, because the processes would kill the enzymes used for ethanol production, Davis said. There's no guarantee that ethanol from trees could be made cheaply enough to compete with petrochemicals and grain-based ethanol.
Farmers should support making ethanol from trees, because it will likely make nationwide use of the fuel additive more politically popular and practical, Davis said. Ethanol is now seen as a Midwest industry.