How Much Energy Can Anaerobic Digestion Produce?

The total energy produced can vary widely depending on factors including what is being treated

Anaerobic digestion is a waste treatment process that breaks down organic matter with bacteria that thrive in the absence of oxygen. Feedstocks can include manure, sewage biosolids, and food wastes. Among anaerobic digestion’s advantages is its ability to treat high-load streams while producing valuable products, including energy. Anaerobic digestion can produce significantly more energy than required to operate the process. But how much more?

The most successful form of anaerobic digestion energy recovery is biogas production. Biogas is 50-75% methane, the main component of natural gas. Although biogas also contains carbon dioxide, it’s considered carbon-neutral because the carbon comes from plant matter and biomethane displaces fossil fuel use. Biogas also contains hydrogen sulfide, water vapor, and traces of other gases.

Purifying the methane in biogas produces another type of natural gas, also known as biomethane, which can be used interchangeably with natural gas and even introduced into the natural gas distribution system.