Draft PPS18: Renewable Energy
Annex 1 Introduction: Landfill Gas
C6. Organic waste materials such as food, paper and garden wastes decompose in landfills to produce landfill gas (LFG), a mixture of methane, carbon dioxide and a wide range of minor components. Using LFG provides energy from a source which would otherwise be flared off or vented to the atmosphere and so wasted.
C7. The total waste produced in the UK is estimated to be about 434 million tonnes per year. Different types of waste vary immensely in their fuel values and characteristics. Municipal solid waste (MSW) and business waste are the largest potential sources of waste derived energy. However the composition and calorific value of these materials can vary markedly. The proportion sent to landfill will fall in the long term as a result of changes in waste management practices with, for example, increasing recycling. The EU Landfill Directive, implemented in Northern Ireland by the Landfill Regulations (Northern Ireland) 2003 , will also progressively ensure the diversion of organic material from landfill, reaching 75% of 1995 levels by 2010; 50% of 1995 levels by 2013 and 35% of levels by 2020. Nevertheless landfill is likely to remain a significant means of waste disposal for some time and the sites will remain biologically active for decades to come.
C8. The main difference between landfill gas systems and other forms of anaerobic digestion is that the landfill itself is effectively the digester, so there are no constructed tanks for this purpose. However, the generation plant used to extract the gas is broadly similar to that employed for other forms of anaerobic digestion.