The 2008 Paris Motor Show today saw Citroën take the wraps off its C4 WRC HYmotion4 concept car, the first WRC car to be equipped with a hybrid energy recovery system that delivers added performance and lower emissions.


This livery of the concept car illustrates Citroën's position on environmental matters, including in the world of motor sport, which stands out as a source of performance-related, reliable and rational technological innovations.

The HYmotion4 system enables a proportion of the kinetic energy produced during braking to be recovered and stored. This energy is accumulated by a motor-generator in the form of electricity in battery packs positioned at the rear of the car. It can then be employed either to deliver extra power when accelerating or to drive the car using emission-free electrical power alone, with no engine noise or exhaust fumes.

This system can significantly enhance the efficiency of a competition car during the different running phases. Firstly, the braking energy is not entirely dissipated in the environment. Secondly, the availability of additional torque - thanks to an electric motor - increases the internal combustion engine's useful rev range. Finally, at a constant speed in electric mode, the vehicle benefits from a longer range (plus 40km), while fuel consumption on road sections is reduced by 30%.

This performance gain makes optimising energy management a new parameter for rally drivers to master.

The date of the first participation in a world rally of the new car has not been released.