Manure as Fuel
A Division of Agriculture engineer has addressed two problems associated with poultry farming using chicken litter. His system will help protect the environment and could reduce individual farmers’ energy costs by as much as 80 percent.
Tom Costello, associate professor of biological and agricultural engineering, worked with a furnace manufacturer in Harrison, Ark., to test a prototype that uses litter as fuel to heat chicken houses. Because it is produced on site, poultry litter is easy and inexpensive to obtain. Its use also can provide heat in place of propane or natural gas, reducing the greatest operating cost for poultry farmers. Plus, the system may help solve the problem of what to do with excess litter.
“Initially, I came to this project as way to protect watersheds,” Costello said. “We know that applying too much litter to the land over a long period can sometimes cause nutrient loading into rivers and lakes, so I wanted to figure out a practical way to help farmers utilize their excess litter. Fortunately, the method will also save them money by reducing operating costs.”
Costello said that if the manufacturer makes recommended design improvements, his projections indicate that 100 tons of litter per year – an amount easily produced at most farms – could generate 80 percent of the annual space-heating needs for one house. The other 20 percent could come from traditional sources.
The chicken manure fuel is renewable and its use decreases greenhouse gas production by reducing fossil fuel consumption. However, it produces an ash containing concentrated phosphorous and potassium, which cannot be applied to land in sensitive watersheds. Still, litter converted to ash results in a 10-to-one volume reduction, and there is a potential market for the ash to be used elsewhere. Further work is needed to quantify air emissions and to develop markets for the ash, Costello said.
The company expects to produce retail units of the furnace before the end of 2007.