Maintaining proper moisture levels in grain after harvesting is a critical process for grain operations. These days, most crop drying operations use some form of powered drying equipment. As the process has become more energy intensive, utility bills have gone up for Wisconsin's agriculture industries.
Focus on Energy, Wisconsin's energy efficiency and renewable energy initiative, works with agriculture producers and processors to help them understand how they can curb high utility bills associated with grain drying. Focus offers expert advice and financial incentives to help producers adopt "best" practices and utilize energy efficient equipment, while producing the most profitable product possible.
As agriculture processes have become more energy intensive, managing costs becomes an even bigger concern," says Rich Hasselman, energy advisor for Focus on Energy's Agriculture and Rural Business Program. "Making the time to assess current practices and equipment can result in significant energy expense savings for years to come."
Grain drying equipment uses natural gas or propane for heat and relies on electric-powered fans to move the heated air through the drying system. Other systems use high pressure fans without heat. While both types of systems dry grain effectively, they also add significantly to a farm's energy bill. As such, it makes economic sense to ensure every grain drying unit is operating as efficiently as possible.
As with any piece of equipment, skipping annual maintenance chores on grain dryers can cost more than operators realize by adding to monthly energy bills and shortening the lifespan of equipment. Factors such as dirty equipment, poorly lubricated bearings and incorrectly calibrated thermostats and sensors reduce a unit's energy and operating efficiency.
Estimates show that routine maintenance of grain drying equipment can reduce energy consumption by 10%. Focus on Energy recommends performing the following equipment maintenance checks at least once a year:
- Keep all components of the drying unit clean, including the floors, columns, screens, fan housings and fan blades.
- Make sure drain holes are open and not clogged with dirt or chaff. Depending on the method of drying used, removing fines from equipment may need to be a more routine task.
- Check belt drives to ensure they are in good condition and at appropriate tension levels. Ensure that pulleys are aligned.
- Ensure all bearings are properly lubricated, and if necessary, tighten all mounting bolts and secure locking collars.
- Check calibration of grain moisture sensors and thermostats and recalibrate if necessary. Consider comparing to a certified unit at a co-op or feed mill.
- Call the gas company or liquid propane supplier and have a certified technician check gas pressure regulators.
- Check the burner flame for proper color (blue indicates complete combustion, yellow signals poor combustion), pressure regulator and inlet air adjustment.
Maximizing energy efficiency
Regardless of the technique used to dry grain, there are ways to make each technique more energy efficient without compromising the end product. Focus on Energy and its program allies can work with the grain operation to ensure a more efficient system.
Retrofitting existing equipment with high efficiency technology is a low-cost way to allow grain operations to save on their energy costs. One option is to install heat recovery on an existing dryer. This method captures exhaust heat from the dryer duct work and is added to the dryer to allow a portion of exhausted air to be re-routed back to the intake. Incorporating heat recovery technology into existing drying methods can save 10% to 20% on energy costs.
Controls are another option in retrofitting that can significantly reduce energy consumption. Controls work by regulating the temperature of the dryer's air based on the grain's moisture level and offers more precise moisture and energy management capabilities. Not all controls are available with a retrofit.
Save with new equipment
Some operations choose to invest in new equipment to achieve lower utility bills and increase efficiencies in the grain drying operation. For example, continuous flow in-bin dryers, mixed flow dryers and column dryers with suction cooling are considered to be the most efficient high temperature dryers available and will reduce energy use and costs significantly compared to other technologies.
One of the advantages of these newer dryers is automation. An automated control system offers more precise moisture capabilities than manually sampling moisture levels. Additionally, the automation allows operators to work on other tasks and not worry about constantly checking and adjusting temperature levels. Many operators have found that automation in the drying process has saved a significant amount of time and energy and improved grain quality.
"There's no one right way to dry grain, but there are ways to improve the efficiency of a chosen practice," says Hasselman. "We recommend producers work with Focus on Energy experts, our program allies, equipment manufacturers and UW agricultural consultants to determine the most efficient and profitable way to dry grain for their particular operation. It's amazing how proper maintenance, updated equipment and fine-tuned practices can positively impact the bottom line."
Focus on Energy offers financial incentives to help offset the costs of installing new or retro-fit equipment. For more information about available financial incentives or Focus on Energy's Agriculture and Rural Business Program, call Focus on Energy at 800-762-7077, or visit focusonenergy.com.