Citroen unveils hybrid World Rally Car

Citroen has taken the wraps off a new hybrid power World Rally Car it believes could lead the way in environmentally-friendly rallying in the future.

Citroen says its new C4 WRC HYmotion4 concept car, unveiled at the Paris Motor Show, is the first WRC car to be equipped with a hybrid energy recovery system which delivers added performance and lower emissions.

The HYmotion4 system fitted to the car enables a proportion of the kinetic energy produced during braking to be tuned into electricity and stored in batteries. A powerful electric motor 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.

Citroen says the system, which is similar to those set to be introduced in Formula one next season, can significantly enhance the efficiency of car, as well as providing more torque, a 40km longer range, and a 30 per cent reduction in fuel consumption.

The key components of the hybrid set up are a 125kW electric motor-generator connected to the rear differential and a pack of 990-cell lithium-ion 400V batteries positioned over the fuel tank. The car carries two additional cooling systems for the motor-generator and batteries, with a specific radiator positioned under the right-hand side of the floor.

Using an electronic control unit to manage the system's power electronics circuit, the driver is free to select one of four running modes, ranging from internal combustion engine mode only, right through to a ‘boost mode’ where the electric motor would add an additional 300Nm-1 of torque for a limited time.

“The C4 WRC HYmotion4 fits perfectly with Citroën's long-term commitment to motor sport and its consequential environmental policy,” said a statement from Citroen. “This concept underpins the brand's policy to conceive very high performance cars which respect the environment and is the first step prior to other developments which will be guided by future evolutions to the FIA regulations.”