Asda has added 50 duel-fuel lorries to its delivery fleet to help reduce its carbon footprint.

The automobiles, operated by Asda Logistics Service (ALS), are powered by liquefied natural gas and the company has established a dedicated refuelling facility at its site in Avonmouth.

Head of central transport for ALS Chris Hall said the greener vehicles are part of a programme aimed at achieving a "ten per cent absolute carbon footprint reduction by 2015".

ALS also aims to cut emissions by 15 per cent across a five year period. To this end, it is testing the use of longer trailers, in an attempt to reduce vehicle miles, alongside cleaner fuel sources.

Managing director for Volvo Trucks UK Arne Knaben said: "We firmly believe in our Methane-Diesel technology and liquefied gas as one of the most important, environmentally friendly, future alternatives to diesel in the short to medium term."

Additionally, it is using double-deck artics for its store distribution operations, cutting down 90,000 journeys and saving the business £10 million a year.