Scientists confirm manure digesters largely succeed at turning farm waste into energy but researchers warned the systems can rupture and when they leak, the environmental damage may cancel out their benefits.

Digesters work by covering manure lagoons and capturing methane gas for fuel, which keeps the potent greenhouse gas out of the atmosphere.

Alyssa Valdez, a climate scientist and doctoral candidate at the University of California-Riverside and the study's author, said it is a powerful tool for reducing emissions unless something goes wrong.

"You can almost think of it like a balloon," Valdez explained. "It does a great job of capturing all that methane, but when it pops or when it leaks, you might see more methane than you accounted for."

Manure digesters are billed as green energy solutions meant to clean up large livestock operations. Alabama's poultry and cattle sectors rank among the largest in the region, making the state a prime candidate for more of the systems. According to the Environmental Protection Agency, poultry manure is the nation's third largest source of methane from livestock manure management. Valdez's findings appear in the journal Environmental Research Letters.

The study found measuring digesters' overall effectiveness is difficult. Farming practices differ dramatically from one operation to the next and from state to state, so clear trends are hard to spot. Valdez added it is why tight oversight and continuous monitoring are essential, especially given methane's extreme potency.

"If we can cut it off at the source, we can mitigate it pretty effectively in our own lifetime," Valdez contended.

Valdez noted while the digesters are key to capturing methane at the source, high concentrations in one area make potential leaks much more environmentally dangerous.

Source: Public News Service