Possibility of legal tailgating in five to 10 years

Truck drivers could be travelling less than a metre from the vehicle in front "within the next five to 10 years" as a means of saving fuel and going green, according to consultancy Ricardo.

It says that platooning - driving a number of trucks extremely close together to ensure high aerodynamic performance - has the potential to cut CO2 emissions at motorway speeds by as much as 20%.

The train of vehicles would be controlled by the driver of the lead truck, who would be in charge of steering, braking and the powertrains of all the vehicles.

Although the concept, contained in a Department for Transport-commissioned report on low carbon technologies for HGVs, is currently not legal, it does merit further work, says Ricardo's head of technology, Neville Jackson.

He says: "It is an important area of research because of the need to improve aerodynamics - the closer you can get to the vehicle in front the more efficient the train becomes. What you need to do is have the vehicles very, very close together, at a distance that would not be safe if it was not electronically controlled.

"The guy at front is effectively driving the whole train - at present the regulations don't allow that, but if you really want to take a step forward, then that's one way to do it. There are plenty of challenges in the way but the potential gains are quite significant."

Jackson says that distances between the vehicles would be less than 1m.

As well as the technological and legal barriers to overcome, Jackson says that there needs to be more research conducted as to how the train would interact with other road users as well as practicalities like how trucks leave or join the train.

But he adds: "If there was a policy decision to do so, then you could have something working along these lines within the next five to 10 years."