Variable-rate speed fans could boost efficiency

Michael Czarick, University of Georgia Extension engineer, talks to Delmarva poultry growers about emerging technology to improve efficiency on their farms. (Photo by Sean Clougherty)

DENTON, Md. — Variable rate technology has permeated agriculture in many ways and its use in broiler house ventilation is on its way, according to University of Georgia Extension Engineer Michael Czarick.
Speaking at a grower meeting in Caroline County and at the National Meeting on Poultry Health, Processing, and Live Production last month, Czarick said variable rate use of fans based on house temperature will greatly boost efficiency and drop energy costs, but the technology is not quite ready for wide use in commercial production.
“I’m not saying run out there and do this, I’m saying look at this and think about when” it’s time to change your houses, Czarick told chicken farmers at the Caroline County 4-H Park on Oct. 8.
Czarick said in large part, ventilation fan design “is about as good as we will get” though one improvement is to install bigger fans.
“No. 1 fan law: All things being equal, the bigger fan will perform better,” he said.
Increasing the fan speed will proportionally increase air output, he added, though the power usage goes up exponentially.
His team’s research shows for every 10-percent increase in the fan’s speed, it uses 30 percent more power.
Using fans with variable rate capability, operated though house’s controller and tied to temperature, his team’s research shows a 30 to 50 percent increase in efficiency and dropped energy use 40 to 65 percent.
Czarick said variable rate use in fans has been happening in Europe for about ten years but he still viewed it as new technology, especially in the U.S. broiler industry. Right now the cost, between $2,000 and $3,000 per fan, is enough to hold most growers back from installing them.
“It’s like a flatscreen TV. Don’t be the first one to buy that flatscreen TV. Just wait a while and the price will come down,” Czarick said. “It’s a mathematics exercise as to when it’s going to be worth it.”
Along with power savings, Czarick cited several advantages of the fan they tested, the BlueFan made by Skov, as staying relatively clean, it’s direct drive so there’s no belt, it has motorized butterfly shutters which help the efficiency, it’s well insulated and comes with an easy-to-use winterizing disk.
He added however, the controllers commonly used in poultry houses still need some advancement to utilize the fan’s capability.
In Czarick’s research, they had to add another controller to only operate the fans, he said.