Audi is presenting the R18 e-tron quattro, its new Le Mans prototype which will have its race debut at the Spa-Francorchamps (Belgium) on May 5th.
The Audi R18 e-tron quattro is a four-wheel driven diesel hybrid which uses a kinetic energy recovery system on the front axle that feeds electricity into a flywheel accumulator before being retrieved back to the electric motors powering the front wheels, and a V6 TDI diesel plant delivering 510 HP (375 kW) to the rear wheels. 
These systems complement each other and create the new e-tron quattro drive principle. The Audi R18 e-tron quattro was developed in parallel with the Audi R18 ultra, a second racer which is identical to the e-tron quattro but does not feature the hybrid drive technology.
Both cars comes with a new gearbox featuring a carbon-fibre composite housing, something which represents a premiere for endurance racing. 
During this year’s Le Mans race (June 16/17), Audi Sport Team Joest will field two R18 e-tron quattro and two R18 ultra prototypes.

Source: Audi