With the introduction of government incentives, anaerobic digestion (AD) is now a viable technology that offers huge potential for revenue generation for farmers and waste operators alike.
Many kinds of organic substrate can be used to produce biogas. In on farm AD-plants, it is mainly animal slurry such as cattle and pig liquid manure. Other organic materials can also be fermented for biogas to increase the biogas production.
Plants that are grown for energy production are known as energy crops. With their help, new biomass can be made available year after year to produce electricity, heat and fuel. The cost of energy crops for growing, harvesting and transportation has to be taken into consideration.
Along with renewable raw materials, non-agricultural substrates are also suitable for the production of biogas, such as residues from the food industry (e.g. pomace, distiller's wash, and grease separator residues), vegetable waste from wholesale markets, food waste or grass clippings and organic waste from municipal waste disposal. The fermentation of residues material (called co fermentation) provides a possibility of closing the cycle and dealing with them in a way that produces few emissions and is hygienic.
The following documents give you an overview over the current status and potential of AD in Ireland.
Biogas barometer Europe: http://www.eurobserv-er.org/press.asp
Further information on Anaerobic Digestion is available in our 'Bioenergy Technologies Section'.