biogas

 Casey Collins, Duke University Energy Manager, inspects a boiler at the West Campus Steam Plant. Soon, these boilers will run on swine biogas instead of natural gas.
James Morrison / WUNC

North Carolina isn’t rich in coal, natural gas or oil deposits, but it has more hogs than nearly any other state. And for many years, people have been trying to figure out a way to turn hog waste into electricity.

biogas
Dave DeWitt

To a visitor, the hog houses down a dusty dirt road outside Magnolia, North Carolina look like any other hog houses.

Here in Duplin County, there are low-slung buildings like this one around every bend, filled with hundreds of thousands of hogs. But this facility is different—just how different can be found down the hill behind the building.

Manure, flowing from the hog house, falls out of a pipe and into an open-air cement tank. From here, it goes to a much larger, circular, blue tank called a digestor.