green cooling initiative: Mobile air conditioning

»Promoting green cooling worldwide«

Mobile air conditioning

Mobile air conditioning (MAC) systems are installed in cars to keep drivers comfortable and cool while driving safely. Vehicles can heat up significantly in hot weather or under direct influence from sunlight, which is the reason why the capacity of MACs in passenger cars lies in the range of around 5 kW – enough to cool a small flat.

In 2006, 20 % of the global refrigerant emissions were from MAC systems in passenger cars. These direct emissions result from leakage during manufacturing, operation, servicing, repair and at end-of-life. Indirect emissions are due to increased fuel consumption caused by MAC operation.

Overview

Subsector Mobile air conditioning
Typical application Almost every car nowadays has an air conditioning system installed. Usually, the compressor is connected to the car engine via a belt for direct transfer of mechanical power. Fans and controls are powered by electricity.
Typical end-users Car manufacturers (OEM, original equipment manufacturers)
Main refrigerants used HFC-134a, u-HFC-1234yf
Charge size approx. 600 g
Natural refrigerant alternative R-744 (CO2)
HC-290 is sometimes used in the aftermarket
Growth rate / future demand High: Strong market increase especially in emerging economies such as China and India
Show on world map.

Scope of improvement: direct emissions

  • Switch to natural refrigerant CO2
  • Hydrocarbons have shown very good efficiency levels especially in high ambient temperature environments and are used in the aftermarket. They are currently not the favoured option because of their flammability, which would require additional safety measures.
  • u-HFC-1234yf has low global warming potential, but inherent safety risks are still being discussed
  • Leakage reduction
  • Reducing end-of-life emissions
  • Reducing overall cooling needs / behavioural changes such as parking in the shade, buying a light-coloured car, heat-reflecting windows etc.


Read more on the scope of improvement: direct emissions

Scope of improvement: energy efficiency

  • Cycle improvements: ejector, high side pressure controller
  • Using CO2 and a two-stage compressor
  • Reducing leakage
  • Reducing overall cooling needs / behavioural changes such as parking in the shade, buying a light-coloured car, heat-reflecting windows etc.

Read more on the scope of improvement: energy efficiency