CornCorn StoverStover forfor BioethanolBioethanol –Your–Your NewNew CashCash Crop?Crop? Suppose someone told you that you could increase the profit from your cornfield by $20 per acre without planting anything else or changing or hurting your existing crop. And that by doing this, you would be doing great things for the environment and helping to fuel America as well as to feed it. Would it sound like snake oil or a late-night TV ad? (What if this was to develop a new business and jobs in your community, supported government programs, and followed clear guidelines on maintaining soil quality?) Biomass ethanol technology is still developing and important questions need to be answered about corn stover removal, but prospects are excellent for you to someday be able to harvest and sell a substantial portion of your stover for fuel production—without hurting your soil or main corn grain operation. Ethanol is already an important element of grain. Just as making ethanol from corn grain transportation fuel production. About 12% of supports corn prices, making it from stover U.S. gasoline sold contains 8% to 10% ethanol would provide farmers with an additional reve- as a fuel additive to boost octane and reduce nue source. Additional technological advances carbon monoxide and other toxic air emis- are still needed before biomass ethanol can be sions. Another 25% of U.S. gasoline now has cost-competitive with grain ethanol and gaso- a petroleum-derived additive that could be line, but the U.S. Department of Energy (DOE) phased out because of water pollution con- has set a goal of having nine commercial plants cerns. Because ethanol can directly replace this in operation using local corn stover for feed- additive, ethanol use could increase stock by 2006. rapidly. Ethanol can also be used as an alterna- Careful and location- Corn stover is in many ways an ideal feed- tive fuel (typically in an 85% blend) to reduce stock for bioethanol production. Although bio- specific evaluation will our dependence on foreign oil (foreign oil cur- ethanol can be made from a wide range be needed to determine rently supplies more than half of our petro- of biomass materials—from wood chips to leum supply). Making ethanol from the starch what portion of stover municipal solid waste to “energy crops” of fast- in corn grain already supports a growing trees or grasses—stover from existing needs to remain in the $2 billion per year industry, with 55 ethanol corn production is by far the most abundant field for erosion control, plants providing jobs and economic stimulus crop residue readily available today. Corn sto- to rural areas in the year 2000 and a dozen moisture retention, or ver is, of course, also available in the same more planned for the future. areas as corn grain, so it is easily accessible to other purposes. In some Biomass ethanol is ethanol made from plants that already produce ethanol from corn situations, on the other non-grain plant materials known as biomass. starch. hand, stover harvest The bulk of most plants is fibrous material Harvesting stover efficiently will require might allow farmers to consisting of cellulose, hemicellulose, and lig- overcoming several challenges. Among other nin. Advanced biotechnology can break down things, corn stover on the ground is inherently reduce their tillage— cellulose and hemicellulose into their compo- contaminated with dirt and other foreign reaping the erosion con- nent sugars, and then ferment those sugars to materials; climatic and soil conditions may not trol and soil quality ethanol. Making ethanol from biomass as well allow timely field drying of stover for safe stor- as starch or sugar opens up the possibility of age; and corn stover collection may compete benefits of minimum ethanol production on a larger scale, by sup- with other crop harvesting operations. A tillage. plementing ethanol production from corn national effort is underway to identify the most efficient ways of harvesting, drying, and Preliminary estimates suggest that fields located moving stover from field to the conversion within about 50 miles of an ethanol plant are facility. With present practices and machinery, more likely to be profitable for stover harvest. corn stover would likely be collected and Grower payments and other cost figures from baled separately, immediately after the corn stover collection experience for a processing grain harvest. Stover bales would then be plant in Harlan, Iowa, can be found at www. stored and transported to ethanol plants in afdc.doe.gov/pdfs/5149.pdf. In this case, a manner similar to current handling of forage farmers received between $9 and $38 per acre crops. As stover harvest becomes common, net profit depending on the amount of stover however, new equipment might allow grain collected and delivery distance. Most ethanol plants and stover to be harvested simultaneously. For the present, while it may seem early are small rural How much stover should be harvested is a to be considering stover harvest for biomass facilities, providing complex question that needs to be carefully ethanol production, there are important evaluated before the option for sale of stover reasons to start thinking about it now. For one jobs and money for becomes widely available. Key considerations thing, you probably do not take changing har- the local economy. Bio- for how much stover can be harvested respon- vesting or tilling practices lightly. You might mass ethanol plants sibly include erosion control, moisture reten- want to look into what your particular condi- tion, winter forage practices, and soil carbon tions mean for stover collection. You may also could probably impacts. The amount of stover that should be need to work with your Natural Resource Con- purchase corn stover, left will also be highly specific to local condi- servation Service representative to modify as well as kernels, tions and topography. your farm conservation plan. You might want to experiment with stover collection on a from farmers within The U.S. Department of Agriculture (USDA) small field. You could use the stover collected about 50 miles of is cooperating with the U.S. Department of for forage or look for other interim uses. (The Energy in performing field studies to better the plant. Harlan group mentioned above, for example, is understand the effect of corn stover removal on now selling the stover they collect for produc- soils in the Corn Belt. Scientists at the USDA, tion of a mulch such as that used as a growth Colorado State University, the National Renew- medium for plantings along highways. For able Energy Laboratory, and Oak Ridge more information, contact Biomass Agri-Prod- National Laboratory are currently engaged in a ucts 712-755-5363) DOE is eager to learn major analysis of harvesting and converting whether or not you would be interested in corn stover into ethanol. This analysis will help harvesting and selling stover when the oppor- determine the overall life-cycle impact tunity arises. We would especially appreciate of ethanol production from stover. Already, this hearing about any particular reasons why you study has found that for the state of or other corn growers would not want to har- Iowa as a whole, 57% of stover could be vest your stover. If you have questions or com- removed without increasing erosion (50% for ments please contact the DOE Biomass mulch-till acreage, 67% for no-till acreage). Feedstock Development Program, at bfdp@ Produced by the Researchers conducting that study are now National Renewable Energy ornl.gov or 865-576-5132. focusing their attention on the impact of stover Laboratory, a U.S. Department of Energy national laboratory. removal on soil carbon levels. As results of this Another reason to think about stover sales now DOE/GO-102001-1273 study develop, they will be made is the possibility of promoting the development Revised May 2001 available on the Biofuels Program Web site of a biomass ethanol plant in your community. www.ott.doe.gov/biofuels/bioethanol.html. Because high transportation costs seriously Printed with a renewable-source ink decrease the profitability of stover collection, on paper containing at least 50% In some regions stover is now tilled under proximity to a biomass ethanol plant will be wastepaper, including 20% postcon- to facilitate spring soil warming. In these sumer waste. a major advantage for stover harvesters. The Neither the United States government regions, stover harvest might make it easier nor any agency thereof, nor any of their majority of grain ethanol plants are small, employees, makes any warranty, express to switch to minimum tillage, thus providing community-based plants, many of which are or implied, or assumes any legal liability additional erosion control and soil-quality or responsibility for the accuracy, actually owned and operated by farmer cooper- completeness, or usefulness of any improvement. information, apparatus, product, or atives. This could quite likely be the case for process disclosed, or represents that its use would not infringe privately owned Revenue potential from stover sale will stover ethanol or combination stover/grain eth- rights. Reference herein to any specific commercial product, process, or service also be highly specific to local situations. In anol plants, as well. Obviously, promoting and by trade name, trademark, manufacturer, general, however, the greater the volume of building an ethanol plant requires a lot of lead or otherwise does not necessarily constitute or imply its endorsement, grain produced per acre, the greater the time. To explore the possibility of developing an recommendation, or favoring by the United States government or any agency associated stover production and therefore ethanol plant in your community, please con- thereof. The views and opinions of sales income. The greater the distance from an tact the DOE Regional Biomass Energy Program authors expressed herein do not necessarily state or reflect those of ethanol plant, the higher the hauling expense at [email protected] or 202-586-8014.