Landfill gas is an alternative form of fuel to fossil fuels in the production of electricity. With landfill sites all over the UK, there is a large resource available. Landfill Gas (LFG) is the product of the degradation of biodegradable waste and it is typically made up of about 50% methane (although this can reach about 65%), with the remainder mainly carbon dioxide plus small amounts of other gases. Both methane and carbon dioxide are ‘greenhouse gases’ contributing to global warming, so their use in this case as fuel reduces their release into the atmosphere. LFG is also a danger to the local environment causing problems for local vegetation, potential fires and explosions and even asphyxiation if released into a building.
Under optimum conditions one tonne of biodegradable waste can produce between 200 and 400 cubic metres of landfill gas. Due to the use of greenhouse gases and the fact that this energy source displaces the use of fossil fuels, landfill gas is deemed to be a ‘green energy’.
Landfill gas can also be used for direct firing (e.g. in brick kilns or for producing steam in boilers) or for direct heating (e.g. in horticultural greenhouses). Again, this reduces the amount of gas released into the atmosphere and can provide an income stream once the landfill site is full.