Anaerobic digestion (AD) is the default process for biological conversion of residue organics to renewable energy and biogas primarily in the form of methane (CH4) in the absence of oxygen.

Different types of biomass and waste can be used for AD such as solid waste, waste oils, animal fat, energy crops, agricultural waste, manure and sewage sludge.

The biogas produced as a result can be used in a number of ways, either directly in engines for Combined Heat and Power (CHP), burned for energy in the form heat or cleaned and used as natural gas or as a transport fuel. 

Read the full Anaerobic Digestion briefing.