SPY ----> PSA Hybride HDi Peugeot-Citroen C4

PSA Peugeot Citroen unveiled Tuesday two prototype cars featuring its new diesel-electric hybrid powertrain, the Peugeot 307 and the Citroen C4 Hybride HDi.

The cars achieve 25 percent better fuel economy than a comparable gasoline-eletric hybrid - 3.4 liters of diesel fuel per 100 km (roughly 69 mpg combined city/highway).

The Hybride HDi system includes a 1.6-liter HDi diesel engine, a diesel particulate filter system, a "Stop & Start" system, electric motor, inverter, high-voltage battery pack and motor control electronics. The Stop & Start system allows the vehicles to start and drive if the batteries are flat, using only the diesel engine.

The prototypes also feature regenerative braking, an all-electric mode (good for 50 kph), and an Extended ZEV (zero-emissions vehicle) mode in which electric power is used by default when battery levels permit.

On the highway, the electric motor is available for a 35 percent power boost for extra acceleration.

The company says its Hybride HDi vehicles could hit dealers as soon as 2010, if the price gap between the hybrid and standard diesel models can be brought down to an acceptable level. Major cost drivers are the high-voltage batteries, the electric motor/generator, the inverter and the regenerative braking system.