Sara Krauskopf, Director of Outreach and Education with the Great Lakes Bioenergy Research Center, GLBRC, brought a fascinating story of the potential attraction and hurdles to making sustainable biofuels.
The Department of Energy is supporting research to explore practicality of bioenergy here at the Univ of Wisconsin and at Michigan State. Biofuels are those produced from biological materials. Despite great interest in their potential, realistically biomass to will replace a fraction of current energy sources (10%?). We shall have to rely on many different sources - solar, wind, hydro, hydrogen, biomass, nuclear, and fossil fuels in the future.

Ethanol, which can be easily fermented from sugar cane and corn kernels, is already being used. While less energy - dense than diesel and gasoline, ethanol provides more energy per unit volume than hydrogen or battery power. There is a federal mandate to increase the volume of biofuel, including ethanol, produced from the current 11 million gallons to 36 million gallons by 2022. There are drawbacks to corn kernels as a source for ethanol - it's food for animals, it's an annual plant and its culture requires chemical inputs that impact water quality. Cellulosic materials, made up of chains of glucose, like corn stalks and cobs, or native perennials like switch grass, would be a better source. Their structure, however, makes breakdown difficult and includes the lignin protective layer, and the long cellulose chain. Research is underway to open up the plant material and to find new ways to convert exposed cellulose to simple sugars. Fungi and bacteria are being studied as enzyme sources since some of them degrade cellulose. Genetic modifications might make lignin more soluble.

Many different features must be measured and balanced to determine optimal energy sources. Biodiversity out in the fields is desirable. The crop should have benefits for the farmers. The ability of the plant to sequester carbon is desirable. Ideally the production would have low toxicities at all steps and the fuel be energy dense. Ability to make plastics from intermediates would be a plus and the energy input at each step of the synthesis and extraction must be determined and subtracted from the fuel yield of the product. Thus, there is need for extensive monitoring of many factors.

Thank you Sara for bringing us this story of current work to realize the potential of converting plant materials to useful fuel. Thank you Ann, for arranging the program.