Mercedes-Benz is bidding to protect its market share by launching a range of new environmental and fuel-saving initiatives.

Sales of vans under 3.5 tonnes gross vehicle weight are down by 46% so far this year and the German manufacturer believes that increasing its ‘green’ profile – and in many cases saving fuel at the same time – will help persuade fleet buyers to choose its models.

In July, new 2.2-litre Euro V diesel powerplants will replace the old Euro IV units on Sprinter, which promise to cut fuel consumption by 11%.

It will be the first time that Euro V engines are available on panel vans of this size.

Later in the summer Mercedes-Benz will launch a new CNG-powered Sprinter, the NGT, which will run either on natural gas or petrol. Power is provided via a 1.8-litre supercharged petrol unit.

Sales of this model are likely to be hampered by the fact that there is no refilling infrastructure in Britain for CNG, but Steve Bridge, van sales and marketing director, believes there will be a healthy demand for the new model from fleets which can ‘bunker’ CNG.

He said: “We looked at an LPG version, which would be capable of being refilled at garages, but we decided it was not an area that was worth investing in.

"We are working on the infrastructure problem at the moment but we believe this van will be of interest to local councils who want to increase their green credentials and London-based fleets, as the NGT will escape the London congestion charge.

"We are also looking at sales to the 2012 Olympic games contractors.”

The biggest problem with the new Sprinter NGT will be residual values – few second-users are likely to want a van which can’t be refuelled at a conventional filling station.

To combat this problem, Mercedes-Benz has decided to build such considerations into its sales package. Bridge said: “We’ll make offers to doubters of CNG through our own contract hire arm and we’ll take the residual value risk.

"We will be competitive on price and we are predicting RVs on a par with Sprinter diesel models.”

Mercedes-Benz has already launched a new EcoStart Sprinter, which switches the engine off when the van has been stationary for two seconds.