Transcript:

Cows poop a lot. On large dairy farms, dealing with all that waste can be a challenge.

Some farmers pile it into pits, where it emits climate-warming methane as it breaks down. But on other farms, cow poop is being turned into energy instead.

A biodigester, or anaerobic digester, is a tank or covered lagoon where microorganisms break down organic waste in an oxygen-free environment.

Niekrasz: “It can be manure from animal agriculture, it can be food waste.”

Jessica Niekrasz consults on biodigester projects and cofounded the Wisconsin Biomass Energy Coalition.

She explains that when waste breaks down in a biodigester, it produces methane and carbon dioxide, which are captured.

This biogas can then be turned into vehicle fuel or used in generators or boilers. Or it can be refined and used in place of conventional natural gas.

And the biodigestion process leaves behind a nutrient-rich material called digestate that can be used as fertilizer on farm fields.

Niekrasz: “It comes back with fewer pathogens, reduced odor.”

So biodigesters provide farmers with products they can use or sell, while reducing the climate pollution caused by all that poop.

Reporting credit: Sarah Kennedy / ChavoBart Digital Media