Bibby opts for LPG in dual-fuel tractors

Bibby Distribution has chosen liquid petroleum gas (LPG) as the alternative fuel for five dual-fuel MAN tractor units in place of the more usually used liquid natural gas (LNG). It estimates that the alternative fuel will save up to £200,000 from its fuel bill over the next five years and cut CO2 emissions by 10 per cent.

The five MAN TGS 26.440 LS units were converted to use both diesel and LPG by G-Volution at a cost of £8,500 per vehicle. G-Volution’s conversion involves fitting an additional LPG tank that is around one-third of the size of the retained standard diesel tank. An on-board computerised optimiser then analyses the engine output requirements during a journey and sources fuel from either tank as required, with the LPG being predominantly chosen when the engine is not operating at peak torque requirement.

A small amount of diesel is always burned as an ignition medium, and LPG meets around 25 per cent of the trucks’ total fuel requirement.

Robert Earl, contract manager at Bibby Distribution, said LPG was chosen in place of LNG because its price appeared to be historically very stable. LPG fuel supplier FloGas was able to provide the depot storage tank as an easy-to-assemble kit, which was installed in a single day.

All five trucks are dedicated to a contract with Unipart Rail, and operated out of the company’s Doncaster depot. Unipart Rail supplies train components through a network of over 90 depots across the UK, and also refurbishes train bogies at its Doncaster site.

The MAN trucks transport the train bogies, and return to the depot daily, making them ideal candidates for the dual-fuel conversion. As they are double-shifted, the high-mileage operation means a relatively rapid return on the extra capital invested.

With LPG costing around £0.50 per litre compared to £1.07 per litre for bulk diesel, it is estimated that the payback period is around 14 months with a minimum saving of £29,000 per vehicle over a five year lifespan – although changes to fuel prices could see this extend to as much as £40,000 each.

Converting the trucks to gas has also enabled Bibby Distribution to help its client meet Network Rail’s Sustainability Charter requirement, which seeks to reduce environmental impacts by promoting energy-efficient transportation.

Duane Trower, logistics operations director at Unipart Rail, said: “Fuel usage comes with both financial and environmental costs, so we were delighted when Bibby Distribution proposed a solution that would help cut both without compromising on service. We’re already seeing substantial savings both in terms of cash and carbon emissions and we’ll be breaking even on the investment in less than 18 months.”