Ferdinand Porsche developed the world’s first hybrid car in 1900 (the Lohner Semper Vivus), and created a sensation at the Paris Auto Show of 1901 when a production version of the car, the Lohner Mixte, was presented to the public. Hence, it is entirely appropriate that, Porsche should introduce the hybrid drive to production-based GT racing. One hundred and nine years after that Paris debut, the Porsche 911 GT3 R with hybrid drive is making its debut at the Geneva Motor Show. The most remarkable aspect is that the two 60 kW electric motors on the front axle drive are not supplied their energy by conventional chemical batteries, but by an electrical flywheel power generator fitted in the interior next to the driver. The energy storage system was originally developed for use in Formula One by the AT&T Williams team but Williams Hybrid Power is now focused on applications in road vehicles.
The car will debut on May 15 at the Nürburgring 24 Hours on the Nordschleife circuit and the focus is not on winning the race, but rather serving as a spearhead in technology and a “racing laboratory” providing know-how on the subsequent use of hybrid technology in road-going sports cars.
The mechanical hybrid technology in the car has been developed especially for racing, and is significantly different in its configuration and components from conventional hybrid systems.
The electrical front axle drive with two electric motors developing 60 kW each supplements the 480-bhp four-litre flat-six at the rear of the 911 GT3 R Hybrid.
Instead of the usual batteries in a hybrid road car, an electrical flywheel power generator is fitted in the interior next to the driver and delivers energy to the electric motors.
The flywheel generator itself is an electric motor with its rotor spinning at up to 40,000 rpm, storing energy mechanically. The flywheel generator is charged whenever the driver applies the brakes, with the two electric motors reversing their function on the front axle and acting themselves as generators.
When accelerating out of a bend or when overtaking, the driver is able to call up extra energy from the charged flywheel generator, the flywheel being slowed down electromagnetically in the generator mode and thus supplying up to 120 kW to the two electric motors at the front from its kinetic energy. This additional power is available to the driver after each charge process for approximately 6 - 8 seconds.
This means that the energy formerly converted into heat upon every application of the brakes, is now converted into additional drive power.
Depending on racing conditions, hybrid drive is used in this case not only for extra power, but also to save fuel. This again increases the efficiency and, accordingly, the performance of the 911 GT3 R Hybrid, for example by reducing the weight of the tank or making pitstops less frequent.
The energy storage system was originally developed for use in Formula One by the AT&T Williams team but Williams Hybrid Power is now focused on applications in road vehicles. The technology will also be developed for larger, infrastructure applications by Williams F1 at its new research facility in the Qatar Science and Technology Park.
Ian Foley, Managing Director of Williams Hybrid Power said, "We are delighted to see our technology being adopted by one of the world's leading engineering companies and most prestigious automotive manufacturers in one of their racing cars. Partnering with Porsche on this project has been a very positive experience and we are grateful to them for choosing to work with us."
Alex Burns, Chairman of Williams Hybrid Power and Chief Operating Officer of Williams F1 said, "This is a milestone for both Williams Hybrid Power and Williams F1. Together we have worked to bring this technology forward to the point where it can be tested in a racing car and deployed in a road car. We hope that this will be just the start of the evolution of hybrid systems developed for Formula One moving across to applications where they can contribute to cleaner and more powerful vehicles."
Williams Hybrid Power’s novel, patented electromechanical composite flywheel system provides a high-power, cost-effective and environmentally friendly solution for mobile or stationary energy storage and recovery.
Though it all began with the development of a flywheel for Williams F1’s Kinetic Energy Recovery System, WHP is commercially developing technology to meet high-power energy storage needs in a variety of applications including hybrid passenger vehicles, hybrid buses, electric trains, diesel-electric ships and wind power generation.
In November 2009, the company announced its involvement in a mild hybrid road car programme with Ricardo, CTG, JCB, Jaguar Land Rover, SKF and Torotrak. The project aims to demonstrate the potential of flywheel-based hybrid systems with the potential for 30 per cent fuel savings (and equivalent reductions in CO2 emissions) at an on-cost of less than £1000, to enable mass-market uptake of hybrid vehicles in price sensitive vehicle applications.
