Because they are more efficient and operate at higher pressures, the particles that they emit are smaller than those from conventional diesel units.

In the years ahead, conventional diesel and petrol cars will go increasingly far on every litre of fuel.

The exhaust gases, he says, smell less like conventional diesel and more like a chip shop.

Ministers are preparing to tackle overpriced electric car charging amid fears that it can cost as much to run a green vehicle as a conventional diesel.

Her nuclear reactor and propulsion plant were removed and replaced by a conventional diesel engine room.