Landfill gas is being used to make liquid biomethane for use as a vehicle fuel - the first time it has been used like this in Europe.
Waste firm Sita and technology provider Gasrec are in the final stages of commissioning plant at Sita's Albury landfill site in Surrey. The landfill produces some 2,500m3 of landfill gas per hour, and this will be used to make 5,000 tonnes of biomethane - enough to power 150 heavy goods vehicles.
The plant works by dewatering the landfill gas, then removing hydrogen sulphide, carbon dioxide and nitrogen. The remaining methane, about 95% pure, is liquefied. According to Richard Lilleystone, Gasrec's chief executive, the resulting liquid biomethane cuts CO2 emissions by 70% compared to diesel, particulates by 90% and SO2 by 50%. The fuel is also around 30% cheaper.
The fuel is being used by Sita, haulage firm Hardstaff Group, as well as Sainsbury's in one of its delivery trucks. It is also being trialled by waste company Veolia in a street cleaning vehicle in Camden, north London, to assess its performance in urban areas. All users have their own refuelling infrastructure at depots.
According to Stuart Hayward-Higham, Sita's head of business development, the firm decided to develop the plant as the economic future for electricity from landfill gas is uncertain. "There are many ways of making electricity, many of which are better than waste," he said. From next April, electricity from landfill gas will only receive 0.25 renewable obligation certificates (ROCs) per megawatt hour of electricity generated. This compares to the current 1 ROC.
Using landfill gas to make transport fuel rather than electricity also offers a significantly larger reduction in CO2 emissions, says the Renewable Energy Association.
403, August 2008, p 25 © 2008 Haymarket Business MediaENDS Report