MOTOR RACING PAVES THE WAY
Exactly 110 years after Ferdinand Porsche developed the first hybrid drive vehicle – the Lohner Porsche Semper Vivus – the sports car producer is revisiting this visionary drive concept in the close-to-production GT racing program. This is a new chapter in the highly successful history of the 911, which has chalked up more than 20,000 victories in 45 years. At Porsche, motor racing is paving the way for the hybrid technology that is to be used in future in all model series. “Our hybrid version of the Cayenne, the 911 GT3 R Hybrid and the Concept Study 918 Spyder demonstrate what we will be able to achieve using modern hybrid technology to build sporty vehicles: top performance at extremely low consumption levels,” says Porsche CEO Matthias Müller.
What really sets the pulse of driving dynamics engineers racing is the electric front-wheel drive, which makes its debut in the 911 GT3 R Hybrid. While it was already possible to brake either of the front wheels individually to optimize traction control, they can now also be accelerated separately. This prevents the vehicle from oversteering and the tail end from swinging out. The drive technology is expected to go into series production in 2013 in the Porsche 918 Spyder in combination with the plug-in battery technology.
The innovative hybrid system with flywheel energy storage in the 911 GT3 R Hybrid was specially developed for racing. Accordingly, it has also been lined up for the 918 RSR, the motorsport variant of the 918 Spyder, which was unveiled at the Detroit Motor Show in January 2011. The system works as an energy accumulator for the two electric motors on the front axle. The flywheel can absorb energy in a fraction of a second and release it again directly. This has a distinct advantage over batteries, which are charged and discharged based on time-consuming chemical processes. A far more efficient alternative is flywheel energy storage, in which a rotor revolves on its own axis up to 40,000 times a minute and stores the energy obtained mechanically. When the rotor slows down, the energy is regained. Another benefit is that the driver can use the boost switch to command extra tractive power from the flywheel, giving the hybrid 911 an extra ten kilometers an hour “on call”. The only bad news is that the flywheel technology is not yet suitable for everyday driving. This is because the rotor only gains sufficient momentum when the brakes are applied frequently and heavily.
Hartmut Kristen likes to refer to the hybrid racing car as a “race lab”. He sees it as an impressive demonstration of the potential inherent in hybrid technology: “The technology that has become a reality in motorsport today will soon be a feature of normal, everyday driving.” To this end, the motorsport team is working closely together with colleagues in the Porsche Research and Development Center in Weissach, which is to be expanded in the near future. The €150 million that Porsche is investing in the center will be spent, among other things, on a state-of-the-art wind tunnel, a new design center and an innovative electronics integration center. The project will also create 100 new engineering posts.
NEXT STOP: SMALL SERIES PRODUCTION
Kristen is extremely pleased with the enormous amount of knowledge gained in such a short time. The next step is now to adapt hybrid technology for small series production, for example for use in one of Porsche’s 19 race car series. Until then, though, the two existing examples of the 911 GT3 R Hybrid will be in action on the racetrack, for example in the 24-hour race on the Nürburgring at the end of June 2011. And the Porsche team expects nothing less than victory.