Audi is committing major resources in order to continue improving fuel efficiency and reducing emissions. The brand is introducing a trend-setting technology concept at the Paris Auto Show: the A4 TDI concept e offers the typically agile experience of driving an Audi, yet it uses just 3.99 litres of fuel per 100 km, which corresponds to a CO₂ output of only 105 grams per km. With this near-production study, Audi demonstrates the great potential of the technologies in its modular efficiency system.

The powertrain of the Audi A4 TDI concept e uses a direct-injection TDI engine with an output of 88 kW and 290 Nm of torque. It propels the sedan from 0 to 100 km/h in 10.7 seconds, and tops out at 206 km/h. An entire array of details – from soft springs on the intake valves to a new thermal management system – improves fuel efficiency. Intelligent technologies are used in the engine’s functional environment as well, such as on the fuel pump and on the automatic air conditioning’s compressor.

The recuperation system is another fundamental component for improving fuel efficiency. It recovers power when braking and coasting to a stop, and temporarily stores it in a battery. A startstop system switches the engine off when the vehicle comes to a standstill. Magnesium was used to reduce the weight of the sixspeed transmission, which received an insulating cover for faster warm-up and modified gear ratios.

Audi uses an electromagnetic servo assembly for steering; electrically actuated brakes are fitted at the rear. The 225/45 R17 tyres have been optimized for road resistance. Sophisticated finetuning measures have improved the aerodynamics of the body. Two types of support are at the driver’s fingertips: he can either call up an economy training program, or have the navigation system calculate the most fuel-efficient route to his destination.