Anaerobic digestion is the natural breakdown of organic materials, usually food or agricultural waste, which produces a biogas consisting mainly of methane and carbon dioxide. The methane is then burnt to generate electricity or is cleaned and fed into the gas network.

The process uses naturally occurring bacteria that break down the matter in a sealed vessel, in the absence of oxygen.

Another product of the process is the residue which is a fertiliser, high in nutrients and can be spread straight on to agricultural land.

Marco Poliafico of Expert Energy has published a paper on Anaerobic Digestion as a business solution for organic waste management.

The key to a sustainable AD is the energy required to transport the fuel to the plant and the residue away.

See our recent visit to a working AD at Barfoots.