As we face the challenging task of developing more sustainable and diverse energy sources, new concepts and modern versions of old technologies, such as wind turbines and biofuels, will be examined, tested, and applied. Discussion, debate, research, analysis, legislation, and, ultimately, the testing of the viability of various options in the marketplace will accompany major changes in the way we obtain energy.

Two articles in this edition of The Illinois Steward discuss potentials and pitfalls accompanying the use of exotic grasses as biofuels. Expert opinions and considerations expressed in these articles are intended to inform our readers, who will play roles as voters, investors, leaders, technical experts, and consumers in changing our energy use and production systems.

Articles in The Illinois Steward on other aspects of evolving energy systems in the region and the world will follow as we chronicle the search for sustainable energy sources.

The Editors

photo by Michael R. JeffordsThe latest report of the United Nation’s Intergovernmental Panel on Climate Change provides the most compelling evidence yet that the globe is warming and that if we continue to combust fossil fuels as we do now, the climate of the globe will change substantially. For Illinois, this means that by 2080 the state’s climate is projected to be similar to that of Texas today. Not only will this move the Corn Belt out of our state, it also will result in losses of many of our native plant species. Within a much shorter time period, the state will warm sufficiently to allow kudzu and other invasive plant species to invade the entire state.

The President’s aim of decreasing gasoline use by 20% within 10 years and more than 30% within 20 years are important steps toward slowing this rate of change, given that the United States emits more greenhouse gases than any other nation. Corn ethanol is an important first step, but it requires substantial inputs of energy in its production that decrease its benefit in reducing  net carbon emissions, in particular high nitrogen inputs. Most fertilizer nitrogen is produced by the energy-intensive Haber Process. A study by the U.S. Departments of Energy and Agriculture assumes that the majority of this replacement of gasoline would be derived by processing of lingo-cellulosic biomass, essentially crop residues, dried dead grass, and wood chips, to derive the so-called “cellulosic” ethanol. The study considered perennial grasses, such as switchgrass and Miscanthus (Miscanthus x giganteus), the most important of these potential feedstocks. Both grasses have the same growth habits as prairie grasses; that is, they provide an annual harvest of dried shoots that may be harvested in the late fall or winter. In the early fall, they move nitrogen and other nutrients to the root system, so that these are retained for the next year’s crop and are not removed in the harvest. Of these two grasses, Miscanthus has proved by far the most productive. Based on trials across Europe, average yields expected in Illinois are 15 dry tons  per acre, without any inputs of fertilizers. Trials across Illinois have confirmed or bettered these projections.

With existing technologies, 1 ton of Miscanthus can be converted to 100 gallons of ethanol, which is very similar to the amount that can be obtained from a dry ton of switchgrass, corn stover, or wood chips. A total of 1,500 gallons per acre exceeds the amounts possible for corn, even if conversion of stover is included, yet the inputs required to raise the crop are far fewer. If 15 tons per acre could be achieved across the Midwest, then 10% of the region’s land would provide sufficient ethanol to replace 33% of the nation’s current gasoline use. With technological, genetic, and agronomic improvements, replacement of 50% or more of gasoline use is feasible, with the potential to make Midwest states the major “oil wells” of the United States. Not only would this potentially bring huge economic benefits to the region and the needed third crop to many farm operations, it would be sustainable locally in improving soil quality and globally in being carbon neutral, that is, providing fuel without increasing carbon in the atmosphere. In Europe where Miscanthus is grown commercially for fuel, several environmental benefits have been noted. These include improvement of soil organic matter content, shelter and nest habitat for animals, improved drainage-water quality, and erosion protection.

Despite these seemingly overwhelming benefits, some researchers have implied that Miscanthus could become an invasive species, and have emotively linked it to kudzu, but without any justification or evidence. It was implied that because the plant is productive without the need for fertilizers or pesticides, it would automatically become invasive. However, this implication omits three key facts about Miscanthus, even though these were well known. Had researchers provided these facts about Miscanthus, it would have been apparent that this particular species is a remarkably low risk.