The stop-start system is just one of a number of ways the German firm will use to reduce its environmental impact.

At the launch of its Q5 Audi introduced a satellite navigation system that plots the most economical route for you to take.

Although the idea is in its infancy, Audi's engineers envisage a future where communication between cars will allow such systems to take the most efficient route regardless of traffic conditions.

Audi realizes that it's not just the technology in the car that can make a difference, but the driver behind the wheel.

Because of this Audi is actively lobbying government agencies to implement greener driving techniques into driver training schemes for learner drivers.

In addition to this Audi's cars will help 'train' their drivers into driving more efficiently via an innovative 'Powerglow' system.

The Powerglow is basically a second-generation development of gearshift indicators that have been making their way into cars recently.

It will glow green or red according to how economically you are driving, while also suggesting the best gear for you to be in.

The power draw from ancillary equipment like heated rear windows and air-conditioning will also be displayed on a 'Comfort Consumption' display.

The Comfort Consumption meter will ensure drivers know exactly how much they could save if such systems were switched off.

The A4 is expected to debut the eco training Powerglow and Comfort Consumption systems next year.