Audi R18 e-tron quattro

With the R18 e-tron quattro Audi provided a drive technology that was unrivalled in the world of motorsport. On the rear axle a V6 TDI engine provided propulsion that was both powerful and efficient.

Seated on the front axle was an innovative Motor Generator Unit (MGU) which Audi had developed along with its system partners. A generator and an inverter converted the energy recovered during braking into direct current which in turn drove a flywheel accumulator located in the cockpit next to the driver. The energy accelerated a flywheel running in a vacuum made and from ultra-light CFC up to 45,000 rpm. The driver could retrieve the energy from the accumulator when required. The flywheel accumulator then fed the two electric motors of the MGU which drove the front wheels – for a short time the Audi R18 TDI was a quattro with four driven wheels. To prevent this advantage from becoming too great, the organisers of the 24 Hours of Le Mans restricted the use of the MGU to speeds of above 120 km/h, to a maximum energy level of 500 kilojoules and to seven sections on the course. This technology was first deployed in the 2012 24 Hours of Le Mans, which Audi won after completing 378 laps and 5,151.762 km. The R18 e-tron quattro was completely redesigned again for the 2014 season. This created the most complex racing car that Audi has ever built. The new LMP1 regulations that came into force in 2014 meant that Audi Sport had to redesign virtually every component. The advanced V6 TDI unit in the Audi R18 e-tron quattro made a crucial contribution to complying with the strict energy specifications of the new regulations. The new R18 had to use 30 per cent less fuel than its immediate predecessor.

Alongside the combustion engine, two hybrid systems were now integrated into the drive concept. As was the case previously, during braking a Motor Generator Unit (MGU) recovered kinetic energy on the front axle which was sent to a flywheel accumulator. For the first time, the turbocharger of the combustion engine was even coupled to an electric motor: This also allowed the energy from the exhaust gas flow to be converted into electrical energy – for example when the boost pressure limit was reached. This energy also went to the flywheel accumulator. Depending on the operating strategy, during acceleration the stored energy could flow back to the MGU on the front axle, but also to the new type of e-turbocharger which then supplied more power to the combustion engine.

Technical data