Published on March 7th, 2014 | by Daniel Sherman Fernandez0
Porsche 919 Hybrid For Le Mans Uncovered In Geneva Show
Porsche returns to the great motor sport stage. The sports car marque is sending a cutting edge technology platform, the new 919 Hybrid, to race in the top LMP1 category of the World Endurance Championship (WEC), which includes the renowned 24 Hours of Le Mans. On the race track and at the Geneva International Motor Show, the LMP1 prototype will be accompanied by the new Porsche 911 RSR, another world premiere in Geneva.
Technology transfer from race course to streets
Motor sport is as much a part of Porsche as the numeric sequence 911. The first sports car from Zuffenhausen was sent to race at Le Mans back in 1951, ie shortly after the company was founded.
Ever since, knowledge acquired in competition has benefited the company’s production models. Developments such as dual ignition, disc brakes, the dual-clutch transmission and powerful hybrid drives were first proven out on the race course before they were introduced into street models. As a result, there is always a race car within every Porsche.
In 2014, Porsche is returning to the top class of endurance racing after an absence of 16 years. Consequently, the engineers had to develop the new Porsche 919 Hybrid from scratch. The new WEC regulations for LMP1 race cars gave them an unusual degree of freedom, while focusing on such technologies with great future potential such as hybridisation, engine downsizing and a systematic approach to lightweight design. Instead of pure power, the focus is now on clever ways to enhance fuel efficiency: only those with fuel-efficient cars are competitive. For a long time now, Porsche has called this ‘Porsche Intelligent Performance.’
The 919 Hybrid is the most complex race car that Porsche has ever put on wheels. It benefits from the know-how that Porsche acquired in producing the 918 Spyder plug-in hybrid super sports car, as well as the hybrid versions of the Panamera Gran Turismo and all-wheel drive Cayenne. At the same time, the LMP1 racer – as a unique test laboratory that is subjected to the unrivalled innovative and competitive pressures of motor sport – has maximum relevance when it comes to the future of sports cars.
Maximum efficiency of all elements as development goal
Porsche engineers are taking on the challenges of the WEC regulations with innovative solutions and all the creativity they can muster. The development of the Porsche 919 Hybrid began in mid-2011 – literally on a blank sheet of paper. As newcomers, the team had to do without the greater experience that their competitors in the LMP1 category enjoyed.
However, they were able to access the know-how that Porsche had acquired in its racing success with the 911 GT3 R Hybrid and the 918 Spyder super sports car, which is also hybrid-driven.
The exceptional efficiency of the highly complex technology of the Porsche 919 Hybrid is the result of a carefully balanced overall concept. From the combustion engine to the energy recovery systems, chassis and running gear, aerodynamics and driver ergonomics, the sum of all individual components forms an exceptionally effective unit. It all serves one goal: maximum sporting performance within tight fuel economy constraints.
In choosing a hybridised drive concept, the newly formulated WEC regulations gave the Porsche engineers great freedom. The drive system of the new LMP1 race car is based on a four cylinder petrol engine that is as compact as it is lightweight. It performs load-bearing functions within the chassis based on its V-angle construction, which also offers thermodynamic advantages. The petrol engine, which reaches a maximum engine speed of around 9,000 rpm, is a front-runner in terms of its downsizing philosophy with 2.0 litres displacement, direct injection and single turbo charging.
It also features two different energy recovery systems. Fundamentally new and especially innovative is the recovery of thermal energy from exhaust gases. An electric generator is used here, which is powered by the exhaust gas stream. The functionality of the second hybrid system is known from the Porsche 918 Spyder. Here, a generator on the front axle utilises braking phases to convert kinetic energy into electric energy. It is also stored in highly-advanced water-cooled lithium-ion battery packs until the driver needs the extra energy. Then the front generator is operated as a single electric motor and drives the two front wheels via a differential in the acceleration phases. This gives the Porsche 919 Hybrid a temporary all-wheel drive system, because the petrol engine directs its power to the rear wheels in a conventional way.