Peugeot will be showcasing its 208 HYbrid Air 2L demonstrator at next month’s Paris Motor Show.

The 2L stands for two liters per 100 kilometers, equivalent to 141 imperial mpg, and is based on a production version of the Peugeot 208 1.2-liter PureTech 82 horsepower 5-seater hatchback.

To achieve such fuel economy, Peugeot said it, with its project partners, used technologies previously reserved for competition and luxury models. Weighing just 860 kilograms – 100kg less than the production car – the concept is a mix of steel, aluminum and composites. Peugeot added engineers embarked on a meticulous selection process to choose only those materials compatible with existing production facilities and a high manufacturing output. In addition, the process involves reducing consumption without altering the car’s characteristics.

Carbon composites are used for the body panels, sides, doors and roof, along with the coil springs for the suspension. In the latter case, the use of composites has a positive impact on dynamic handling by reducing unsprung weight. Peugeot also stated the demonstrator vehicle has been fine-tuned aerodynamically, with a number of improvements to reduce drag, including a lower stance on the road.

The search to reduce weight has not focused solely on the use of new materials; it has also sought to redesign existing parts, added Peugeot. This has led to changes in the thickness of the stainless steel exhaust system, enabling a 20 percent improvement on this part alone.

The standard powertrain has been replaced by a hybrid drive system featuring a mix of gasoline and compressed air. HYbrid Air technology combines two types of energy: the compressed air is used to assist and even replace the gasoline engine to enable maximum efficiency during transition phases, such as acceleration and starts.

The system includes:

  • a compressed-air tank located below the trunk
  • a low-pressure tank near the rear axle acting as an expansion chamber
  • a hydraulic system consisting of a motor and a pump in the engine bay

The hydraulic system features bespoke epicyclical transmission to strike the right balance between the two different energy sources. This replaces the manual transmission and enables automatic shifting.

In Air (ZEV) mode, the car runs on compressed air alone, said Peugeot. This method of driving does not consume fuel and gives off no CO2 emissions. In gasoline mode, the car is powered only by the 1.2-liter engine. This is more suitable for traveling at a steady speed on main roads and highways. The Combined mode is designed for transition phases in urban environments, such as standing starts and acceleration. Peugeot stated it draws on the two energy sources in proportions adjusted to achieve optimal fuel consumption.

The compressed-air tank is recharged when slowing down (while braking or taking the foot off the pedal) or by part use of the energy developed by the three-cylinder engine to compress the air. Both methods can achieve maximum pressure in 10 seconds.