Diesel engine exhaust contains pollutants such as nitrogen oxides and soot particles. Although governments from the late 1990s onward encouraged their uptake in the belief they were more environmentally friendly than gasoline equivalents, it has since been argued that diesel cars produce more than four times as much pollution.
For the automotive sector, the solution was the introduction of regulations to discourage the use of diesel vehicles, while accelerating the uptake of electric vehicles. For commercial vehicles, however, it is not so simple. For all the bad publicity diesel has generated in recent years, there is simply nothing that can match this fuel for its energy density, reliability and durability.
Electrifying smaller, lighter vehicles is one thing. For buses and long-haul vehicles though, diesel is far superior at generating the torque needed to keep them moving. That's not to rule out the viability of electric, hybrid or hydroge…