Shell has launched a new diesel fuel that it says will dramatically reduce the smoke emitted by commercial diesel vehicles while steam cleaning deposits from inside the engine to create a better fuel system.

Aquadiesel is an emulsification of 85% diesel, 13% water and a 2% proprietary additive, with the water in the diesel allowing it to be combusted completely and more cleanly.

Shell says the air quality benefits of Aquadiesel include reducing particulate matter by up to 60%, reducing smog-creating oxides of nitrogen (NOx) emissions by up to 15% and reducing carbon monoxide (CO) emissions by up to 50%.

An added bonus is that there is no need for modifications to most existing diesel engines or fuel storage facilities, which are required by many other diesel alternatives.

Brett Coleman, commercial fuels marketing manager for Shell Australia, said: "We are offering our commercial customers a fuel that provides real environmental benefits - especially for truck, bus and ferry fleets, and underground mining operations."

The fuel has also received a thumbs up from the Central Victorian Greenhouse Alliance which helped to facilitate trials of the fuel in 2001-2002. The Alliance includes nine local governments, seven regional state government agencies, non-government organisations and business agencies.