Ohio State University agricultural engineers are reacquainting farmers with natural-air grain drying - a low-energy drying system that boosts grain quality by increasing test weights and potentially cutting energy costs in half, compared to more commonly used high-temperature drying systems.
Robert Hansen, an Ohio State University agricultural engineer with the Ohio Agricultural Research and Development Center, said that natural-air grain drying is an option for farmers looking to store corn on their farm long-term either for livestock feed or to compete in the marketplace as a shelled corn supplier to an ethanol plant.
"Natural-air grain drying diminishes the need for fossil fuels and fits into certain farming situations," says Hansen. "Compared to using fuel as a source of heat to dry grain, the cost of energy stored in natural air is zero, so farmers are saving themselves money using this system."
Hansen will be at Ohio State University's Farm Science Review to educate farmers on the equipment and the costs of setting up a natural-air grain drying system. His topic is part of a more comprehensive program on grain systems handling that includes grain storage, grain safety, grain bin maintenance, and insect control. OSU Extension and Purdue Extension specialists will be presenting such topics at various locations during Farm Science Review. Farm Science Review will be held Sept. 18-20 at the Molly Caren Agricultural Center in London, Ohio.
A natural-air grain drying system involves transferring wet corn (20% to 24%) directly to bin storage and letting natural-air drying fans -- located underneath a perforated floor -- dry the grain to the optimum 14% to 16% over a 25-30 day period. By comparison, high-temperature drying involves drying wet grain at 200-220 degrees Fahrenheit to 15-16% moisture, and transferring the hot grain to a bin for cooling and storage. Cooling can take anywhere from four hours to 12 hours depending on the type of high-temperature drying system used. High-temperature drying is most suited for farmers growing corn for the harvest time marketplace.
Hansen said that several farmers across Ohio have been using natural-air grain trying for years with proven results. However, the majority of farmers still have not embraced the technology. According to a study conducted by Hansen and his colleagues, 80% of Ohio's corn growers dry at least part of their corn directly on their farm, yet only 11% use natural-air grain drying.
"Farmers tend to shy away from the system because there are restrictions on the magnitude of incoming moisture content and management requirements are high, but it is well worth it in the long run," says Hansen.
For various high-temperature drying systems, propane is used, while natural-air drying systems can be operated without fuel. And while the quantity of electrical energy used for natural-air drying is higher, overall energy consumption is lower. Using today's costs of propane ($1.40/gallon) and electricity ($0.12/kwh), overall energy costs for a natural-air drying system are 40 percent to 50 percent lower than a high-temperature drying system.
"With today's high fuel prices, a natural-air drying system becomes doubly valuable and worthwhile to look in to," says Hansen.