Waste management is an ongoing problem not only within the UK but also on a global basis.
Each year the UK alone landfills 100 million tonnes of waste and one tonne of biodegradable waste produces between 200m3 and 400m3 of landfill gas which contains typically 50% Methane CH4 with most of the remainder being Carbon Dioxide CO2.
Landfill Gas is one of the largest sources of methane emissions to the atmosphere. If methane is released into the atmosphere it is a potent greenhouse gas. In fact, its global-warming potential is 21 times greater than that of carbon dioxide. It is also a danger underground - potentially migrating off site to nearby buildings and creating an explosive atmosphere. Landfill gas has to be dealt with to prevent both its emission to atmosphere and its danger to surrounding property.
Landfill gas can be flared (the simplest option), converting the methane to CO2 but using it as an energy resource both displaces fossil fuel use and encourages more efficient collection, minimising emissions to atmosphere. For this reason, energy recovery from landfill methane has considerable benefit to the environment: reducing global warming on two fronts.
Landfill gas is extracted from landfills using a series of wells and a flare system. This system diverts the gas to a central point where it can be processed and treated depending upon the ultimate use for the gas i.e. either to be flared off or used to fuel a generator.
At ENER·G our service includes both providing gas collection networks (through our sister company Biogas Technology Limited) and use of the collected gas to produce renewable energy.
Particular management of the gas-fuelled engine in the generator system enables the impure and contaminated landfill gas to be used as a fuel. The damaging effects of the contaminants in the gas are minimised by adapting the engine's operation and adopting a tailored maintenance regime. With its wealth of experience in running reciprocating engines on landfill gas, ENER·G Natural Power Ltd is able to optimise output whilst minimising costs.