11 Ways to Cut Grain Drying

Recently Agriculture.com looked at the best ways to cut into grain drying.  Here is what they came up with.

Drying grain can be one of the most energy-intensive operations on the farm. When you burn fuel to produce that energy, you also burn money. 

There isn’t an easy solution to cut costs. “No two farms are the same,” says Gary Woodruff, GSI. “There isn’t one best way to dry grain.” 

This list will help you identify energy-saving tips for the size of your operation and your grain-drying infrastructure.

1 Run in all-heat mode
“One thing that’s been around for a long time but is still cost effective is running a portable dryer in the all-heat mode,” says Woodruff. 

In all-heat mode, you heat the grain in the dryer and cool it in the bin. “The advantage is you can come out of the dryer at a higher moisture content, and then you lose one, two, or three points of moisture in the cooling process,” explains Kerry Hartwig, Sukup Manufacturing Co. “Drying those last points takes the most energy.”

That can save you 20% to 30% of your operating costs, says Woodruff. Running in all-heat mode also increases your efficiency, because grain flows through the dryer more quickly. Plus, you end up with better quality grain, because cooling grain rapidly can increase stress cracks on corn kernels. 

There are limitations to running in all-heat mode. This drying system won’t work on most bins larger than 50,000 bushels. That’s because you need to run between 1∕3 and ½ cfm of air through each bushel when the bin is full. For bins 50,000 bushels or smaller, you will need to have larger aeration fans and increase the number of roof vents. It will also require more management. 

“There are better drying systems on the market that don’t require the extra management that all-heat mode requires,” says Woodruff, “but this is one of the least expensive ways to improve how you process grain on your farm.”

2 Buy an all-heat dryer 
If your present dryer can’t run in all-heat mode, consider upgrading. “A new all-heat dryer gives the most capacity, efficiency, and quality for the dollar, even with the bin aeration upgrades required,” says Woodruff.

3 Upgrade to vacuum cooling or heat recovery
“For larger operations, it will be more efficient for grain to come out of the dryer cool,” says Hartwig. “That’s where vacuum cooling or heat recovery can make a big difference.”

In vacuum cooling, heat that is given off by the cooling grain is cycled back into the drying process. By doing this, less fuel is required to raise the drying air temperature.
Vacuum cooling is offered on tower dryers, centrifugal dryers, and centrifugal stack dryers. 

“With vacuum cooling, you can dry grain with even better efficiency than you can with all-heat drying,” says Woodruff. “You will spend more money up front, and you’re going to need a pretty good size grain dryer to get that newer technology.”

4 Dry grain evenly
“If a dryer dries grain faster in some areas and slower in others, the dryer will overdry grain to make up for the underdried grain,” says Hartwig. “This adds drying cost in extra fuel used and lower grain test weights from overdrying.”

There are different systems available to help you dry grain more evenly. Sukup’s single-module and stacked dryers use a quad-metering roll system that pulls dryer grain near the inside of the grain column out of the dryer faster, while leaving wetter grain near the outside of the column in the dryer longer. Stacked dryers also use a grain cross-over system that takes grain from one side of the dryer on the top module to the other side of the dryer on the bottom module. This inverts the grain for more even drying. Sukup tower dryers use a grain exchanger system halfway down the heat chamber.

Another option is to use a system like GSI’s grain inverters. The inverters move all grain, except the outer 2 inches within the column, to eliminate overdried grain and to maximize drying efficiency. The inverters redirect the warmest grain from the inside of the column next to the wettest grain at the outside of the column. The wet grain is dried by the captured heat, which recovers up to 15% of the heat that would have been lost.

5 Run at a higher plenum temperature
“One thing you might not be aware of is that the higher you run your plenum temperature, the more efficiently you dry grain,” says Woodruff. “At the end of the season, farmers will say they are only removing three to four moisture points, so they lowered their plenum temperature to save some fuel. Exactly the opposite happens.”

Running at a higher temperature reduces the drying time and, therefore, saves you fuel. However, higher temperatures can potentially do more damage, so you need to find a good balance. “Each dryer’s airflow and column management is different, so you have to balance efficiency with quality,” says Woodruff. “There will be a maximum best temperature for each type of dryer.”

6 Do preseason maintenance
Before you start drying grain, make sure there are no obstructions in the columns and that the burner is ready to go. During harvest, empty, clean, and restart the dryer once a week to make sure the dryer is performing optimally. 

“Like any other piece of equipment, if you don’t take the time to clean it and keep it in operating mode, you are probably going to reduce your efficiency,” says Woodruff.

7 Avoid overdrying
Grain needs to be dried to a safe moisture level so it can be stored. This can range from 13% to 15%, depending on how long you will store the grain. However, you want to avoid overdrying. Grain takes more energy per point of moisture removed. So drying beyond the desired moisture level will eat up extra energy.

8 Use a remote monitoring system
One way to keep from overdrying is to use a remote monitoring system. These systems differ for each manufacturer, but most will allow you to monitor all dryer controls just like you would at the dryer from a smartphone, tablet, or other device. 

“Farmers want to be able to monitor their dryers in the combine, at home, wherever they are,” says Hartwig. 

With some systems, like Sukup’s remote monitoring and GSI’s WatchDog, you can also make adjustments remotely. 

“The only thing you can’t do is start the dryer without being there, because that would be dangerous,” says Woodruff. “You can adjust things like the plenum temperature, moisture control setting, and unload limits.”

Beyond avoiding over-drying, remote controls will also ensure that the dryer is running efficiently and hasn’t stopped for some reason. 

“The average dryer puts 2,500 bushels through an hour,” says Woodruff. “In 10 hours, that’s 25,000 bushels. If your dryer isn’t running for that long, that can make a huge difference.”

9 Manage dryability for different hybrids
“There is a lot of variation in the way different corn varieties dry,” says Hartwig. “Even with the same hybrid, there can be drying differences in different years.”

Woodruff says this has become more of an issue in the past five years. His recommendation is to closely monitor your dryer when you change fields or when you’ve changed varieties to make sure the dryer is running where you think it should be.

10 Check moisture controls
To make sure your dryer is running properly, pull samples, check the moisture control, and make sure the dryer is where it is supposed to be. 

“Moisture sensors are temperamental. It only takes one little stock of grain hanging up in the wrong place to throw their values off,” says Hartwig. “You should pull samples two to three times a day.”

11 Get an energy audit
“Sometimes you need someone who is willing to look at your entire operation to make sure that you are operating in the best way you can for your system,” says Woodruff. 

One way to do this is to get an energy audit. Your local NRCS office should have a list of businesses that conduct professional energy audits. 

A USDA REAP grant is available to help you upgrade your system if you can increase your efficiency by 25%.

“If you pursue a grant, work with a grant writer,” advises Woodruff. Learn more about the grant at Rurdev.usda.gov/energy.