Peugeot has introduced its first concept using the PSA Hybrid Air technology at the Geneva motor show. The 2008 Hybrid Air crossover is part of Peugeot's plans to reduce the average CO2 output of its range to 116 g/km by 2015.

Hybrid Air comprises a conventional petrol-powered internal combustion engine, mated to a bespoke epicyclic automated transmission, assisted by a hydraulic motor that’s powered by compressed air. The motor and a pump are positioned in the engine bay on the transmission, fed by a compressed air tank underneath the car, running parallel to the exhaust. The motor and pump can refill the tank with air through harnessing the energy of regenerative braking.

The 2008's internal combustion engine has been extensively reworked to further boost its efficiency. The 1.2 VTI uses 'Diamond Carbon' coating on its components to reduce friction by 30 per cent and split-cooling to reduce warm-up time. It is also 21kg lighter than in previous installations.

The Hybrid Air system is able to run in three modes; in Air (ZEV), the hydraulic motor powers the car using the compressed air stored in the tank; the petrol engine isn't active. As the air depressurises, it displaces a corresponding amount of oil, which runs the hydraulic motor.

The 2008 Hybrid Air can run on petrol power alone, typically when out of urban environments. Combined mode uses both the petrol engine and hydraulic motor to power the car when increased performance is called for. The hydraulic motor can be driven off the compressed air reserves of its pump.

Peugeot claims the technology is capable of a 45 per cent improvement in urban fuel consumption, as a Hybrid Air-equipped car would be running in Air mode for 80 per cent of the time in town. In a B-segment car such as the Citroën C3, emissions of just 69g/km and fuel economy of 97.4mpg have been claimed. The PSA group aims to use Hybrid Air technology to develop a 140mpg car.

The Geneva motor show also marked the debut of the standard Peugeot 2008.