The cost of drying corn — especially the propane bills — add significant expense at harvest time. According to a case study conducted by Mark Hanna, agricultural engineer for Iowa State University Extension, propane accounts for more than 90% of the energy used in high-temperature corn drying. "Considering that propane makes up such a large proportion of the energy needed for drying, farmers may want to compare their own propane consumption to the measurements from the case study," he says.
Led by Hanna, ISU Extension specialists at three ISU Research and Demonstration farm locations collaborated to measure the propane and electricity used for grain drying during 2013 harvest season. Participating ISU farms included the Northeast farm near Nashua, Armstrong farm near Atlantic, and Ag 450 teaching farm at Ames. Additional support for this project was provided by a grant from the Iowa Energy Center.
Farmers can compare their own propane consumption
Ambient air temperatures and different drying techniques were examined in the first year of this study—2013. The study is continuing this fall.
Farmers can compare their own propane consumption to the measurements from the ISU study. On the farms, energy measurements were collected measuring amount of propane used; electrical energy was also recorded for drying fans and mixing augers. Although propane was responsible for up to 98% of energy used in high-temp systems, initial grain moisture really matters. It took as much as 210 gallons of propane to dry 1,000 bushels of 24% to 25% moisture corn compared to as much as 100 gallons for corn below 20% moisture.
A new publication from ISU Extension and Outreach illustrates the first year results of these efforts. Energy consumption during grain drying (PM 3063C) is available to download from the Extension Online Store.
Energy use is affected by initial moisture content of corn
"The case study shows total energy consumption during drying was primarily affected by the initial moisture content of the corn," Hanna says. "Initial corn moisture content and air temperature will be different this year but we plan to collect additional measurements this fall."
Hanna was recently honored with the Dean Lee R. Kolmer award for his career achievements in applied research at Iowa State University. For more information about his farm energy efficiency research and outreach, visit farmenergy.exnet.iastate.edu or follow @ISU_Farm_Energy on Twitter.
The Farm Energy publications are part of a series of farm energy efficiency resources developed by ISU Farm Energy. This outreach effort aims to help farmers and utility providers to improve on-farm energy management and to increase profitability in a rapidly changing energy environment.