The technology used to convert methane from farm waste into usable energy is effective but has risks, according to new research.

Scientists say manure digesters are susceptible to rupture, and when they do, the fallout outweighs the environmental benefits they create. Digesters work by sealing manure ponds and capturing the gas they produce, which is then converted into methane and used as energy.

The process also keeps the gas from warming the climate. Environmental science researcher Alyssa Valdez, a PhD candidate at the University of California Riverside, said that can have a big effect on reducing greenhouse gas emissions – unless they leak.

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

Critics have called digesters costly and inefficient, and contend federal grant dollars often used to establish them could be better used by farmers who are pursuing environmental safety and sustainability in the operations.

Research says the overall impacts of digesters are also notoriously hard to evaluate. That's because management practices on individual farms and even from state to state vary widely, making it hard for trends to develop.

Valdez said they require tight oversight and constant monitoring because of methane's potency.

"It's 80 times stronger than carbon dioxide," said Valdez, "so we don't wanna create large emissions of it into our air, into our environment."

Valdez added that 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