Various compressed air-powered vehicles – of both the two- and four-wheeled variety – have graced our pages over the years, but with a few exceptions, such as Volvo’s Air Motion Concept, major automotive manufacturers have generally shied away from such technology. PSA Peugeot Citroen is bucking this trend with its “Hybrid Air” powertrain that addresses the limited range of compressed air energy storage technology by combining it with a gasoline powered internal combustion engine (ICE). The company plans to have Hybrid Air powered vehicles on the road by 2016.
PSA’s Hybrid Air technology is similar to current battery electric hybrid vehicles, such as the Toyota Prius, but it uses compressed air for energy storage rather than batteries. A hydraulic pump/motor unit recovers energy generated by the ICE and from braking and deceleration, storing it in a compressed air energy storage unit.
Like many conventional hybrids, the Hybrid Air system uses an electronic management system that independently adjusts different modes based on the current driving needs. For highway driving, the system will rely only on the ICE, switching to air power only below speeds of 70 km/h (43 mph). When more power is required at lower speeds or when the compressed air energy storage needs topping up, the system will run in combined mode.
PSA says for city driving, its Hybrid Air system provides fuel savings of 45 percent and increases a vehicle’s range by 90 percent compared to conventional engines with the same power rating. In standard body styles, such as the Citroen C3 and Peugeot 208, the company says the system achieves certified fuel consumption (combined cycle) figures of 2.9 l/100 km (81 mpg) and CO2 emissions of around 69 g/km.
For drivers that spend most of their time in town, Hybrid Air-powered vehicles can run on air power alone for 60 to 80 percent of the time (depending on traffic density) which cuts CO2 emissions even further according to PSA. In line with this, the company sees its new Hybrid Air engine is a “key step toward fuel consumption of 2 l/100 km” (117.6 mpg). Via Peugeot Citroen to introduce compressed air hybrid by 2016.