Audi has pressed ahead with the development of a range of new racing technologies for the 2012 endurance campaign, introducing the Audi R18 e-tron this week.
Diesel power remains the primary propulsion provider, as is now expected for a Le Mans frontrunner, but - the big news for 2012 - Audi has added a diesel hybrid drivetrain using a kinetic energy recovery system (a similar system to Formula 1) and all-wheel drive to the R18 e-tron quattro and the R18 ultra.
To showcase the new diesel-electric hybrid tech, Audi will be fielding a pair of each of the 2012 R18s at Le Mans and Spa, before contesting the FIA World Endurance Championship.
As in F1, the kinetic energy recovery system recovers energy under braking, feeding it into a flywheel. Under acceleration, the flywheel releases the energy to the front wheels at speeds above 120km/h, while the rears are driven by the 375kW V6 TDI.
Why only above 120km/h? Most likely because releasing the torque of a flywheel storing all that kinetic energy would fry the fronts at lower speeds - and probably induce wild understeer.
"Quattro, TFSI and TDI are three excellent examples of how motorsport has stimulated production development," Audi Motorsport, Dr Wolfgang Ullrich, said.
"A similar tendency is apparent with the e-tron quattro - we test a completely new technology on the race track before it's introduced to the Audi production line."
Racing alongside the R18 e-tron will be a pair of R18 ultra prototypes.
The "ultra" designation refers to the ultra-lightweight construction of the cars, with one of the major savings being a carbon fibre gearbox housing, a first for the category.
The e-tron and ultra's first outing will be in May at the World Championship event at the famous Spa-Francorchamps track in Belgium, before the assault on the Le Mans 24 Hours in June.
The 2011 Le Mans winning trio of Fassler, Lotterer and Treluyer will once again share a car, and the second e-tron will be driven by the formidable team of Capello, McNish and Kristensen. The cars will then contest the FIA World Endurance Championships.