Think about this: Iowa alone produced 2.4 billion bushels of corn in 2014. That’s billion, with a B. I wish I had one of those corny “that’s enough to fill Lambeau Field 10,000 times” stats to drive the point home, but just trust me: it’s a lot. Of course, of those 2.4 billion bushels, only a fraction of that crop can be used right away. A large portion has to be stored. This presents its own set of issues.
If Moisture Must Abate, Aerate
When wet grain comes in from the field, it goes through a grain dryer to remove moisture and prepare the grain for storage. Corn, for example, is typically stored with moisture content of 15% or below. The issue is not so much with the moisture content of the grain going into storage (as long as it’s below the magic 15% number); it is that the grain goes into storage at or above outdoor air temperatures at harvest time.
Remember the classic movie Witness with Harrison Ford? I won’t spoil it, but as the final showdown with the bad guys demonstrates, these storage bins are huge. When the outdoor air temperature drops, the grain and surrounding air on the outside of the bin cools down while the interior grain and air stays warm. As the warm air rises and the cool air sinks, currents of moving air (convection currents) transfer moisture to pockets within the grain. Before you know it, the grain starts to spoil.
To prevent these moisture issues, storage bins are equipped with aeration fans that force air through the grain to keep temperature differences minimal and prevent convection currents from forming. Aeration fans are also often used during initial storage to remove the last couple percentage points of moisture from the grain. Due to the large pressures involved with forcing air through grain, it is not uncommon to see multiple 40 to 60 horsepower fans used for aeration. Knowing when and how often to use the aeration fans involves a lot of guesswork. Most of the time, erring on the side of caution leads to operating the fans more than necessary. With the large motors involved, the wasted energy adds up fast.
Take Back Control
Technologies that are quickly gaining in popularity are aeration fan control systems with integrated moisture or temperature sensors. The sensors are buried in the stored grain and can sense where and when moisture or temperature problems occur. This takes the guesswork out of aerating storage bins, preventing spoilage and unnecessary fan usage. Oftentimes, fan runtimes can be reduced by 400 or more hours per year and energy savings are enough to achieve paybacks of 5 years or less.
Aeration fan control systems take the guesswork out of grain storage aeration. Not only will they help prevent spoilage and lost product, they will also save money on the energy bill and help fill Lambeau Field with something other than championship trophies.
 One bushel equals about 56 pounds
 Ha-ha. See what I did there?
 I’m using the term classic very loosely
 I did it again!
 Sorry Vikings fans