Brakes saw NOx emissions fall by 47% following a nine-month trial with 50 DAF LF 230 fridge trucks powered by Shell Gas-to-Liquid (GTL) fuel.

The supplier to the foodservice sector also found the requirement for periodic static regeneration of the diesel particulate filter (DPF) was virtually eliminated, which also has a beneficial effect on fuel efficiency.

The Shell GTL Fuel, supplied to the UK from Certas Energy, was introduced in October 2017 at Brakes’ Premier Park operation in Park Royal, London, in a bid to cut vehicle emissions across the capital. It requires no vehicle modifications or changes to service intervals.

Figures obtained on the pilot programme have now been confirmed in independent, third-party tests by analysts at the Millbrook vehicle testing facility in Bedfordshire.

Steve Webster, Brakes’ head of indirect goods and services procurement, said: “The feedback from the drivers has been overwhelmingly positive – the vehicles are running more quietly and we've seen a substantial reduction in the need to clean the particulate filters.

"The evidence has come back clearly showing that running Shell GTL Fuel in a city centre has a big impact on NOX emissions – indeed, our own test saw a 47% reduction compared to running on diesel.

“We have not waited for future technology either as there is no requirement to convert the vehicle. Shell GTL Fuel is available to use straight away in all diesel engines although operators may wish to confirm with their dealer that the fuel is approved for their vehicle warranty.”