Online retailer Ocado is trialling an electric delivery van to see if it could be a viable alternative to its fleet of diesel-powered vehicles.

If the trial was successful, the vans could replace the 500 Mercedes Sprinter vans currently used by the online retailer and become a regular feature on British roads, said Ocado.

The electric van, which can hold 50% more shopping than the Sprinter, was part of a strategy "to always look for alternative ways to be greener", it said.

Both Tesco and Sainsbury's have a number of electric vehicles in their fleets and Sainsbury's said it would have 20% of its vans running on electricity by September.

The 5.5 tonne Ocado van, made by Isuzu and Zeroed, is powered by an electronically-controlled electric drive train and is driven with a two-pedal system.

Energy is supplied from lithium ion phosphate batteries mounted in cassettes under the body. These are charged overnight for about six hours and will cover more than 100 miles with a top speed of 55 mph.

An electric fridge cools the van's body then uses the waste energy to heat the driver's cab.

As the battle for the green pound becomes fiercer, Ocado claimed to be the only retailer to take back and recycle all its plastic bags.

The Grocer's latest online shopping survey this month (The Grocer, 5 April, p24), indicated retailers were becoming better at packing groceries in fewer plastic bags, with Tesco even offering a bagless delivery option. Ocado cut the number of bags used from seven to 10.