Dukes team up for AD pilot project in NC

By Lisa Gibson | October 21, 2010

A pilot anaerobic digestion project at a hog farm in North Carolina could serve as a model for other hog operations looking for ways to manage waste and generate their own power.

Duke University and Duke Energy have teamed up to develop the system at Loyd Ray Farms, a 9,000-head hog finishing facility in Boonville, N.C., 115 miles west of Raleigh. The project, expected to be operational in February, will use off-the-shelf technology including a lined and covered anaerobic digester and a lined aeration basin.

“The project is about learning a lot together,” said Jason Walls, spokesman for Duke Energy. Besides the benefit of the pilot plant acting as a model and reference for other farms, Walls said the real value of the project comes in two key areas. First, it would help fulfill a portion of the state’s renewable portfolio standard that requires a certain percentage of electricity to be generated from hog waste. “It also helps us better understand how this power plant interacts with our existing equipment,” he said.

The project is expected to generate 512 to 639 megawatt hours of energy per year, all of which will be used at the hog farm. In exchange for hosting the experiment, hog farmer Loyd Bryant gets the system at no cost and will own it after 10 years, according to Walls.

Up to $500,000 of the $1.08 million project has been provide by USDA and the North Carolina Department of Environmental and Natural Resources Lagoon Conversion Program, according to Duke University. The university and Duke Energy will share the remainder of the construction costs and provide the majority of support for the first 10 years of operation and maintenance.

Besides solid hog waste, the system will also be capable of handling liquid wastes such as raw wastewater from the animal barns. After the wastewater is treated through the process, it will be recycled as flush water for the hog houses, according to the university.