green cooling initiative: Chillers

Air conditioning chillers

Chillers contain water, which is cooled, and is then distributed over longer distances, for example to cool whole buildings (air-conditioning chillers) or industrial processes such as plastics and rubber manufacturing and food processing (process chillers).

The cooling capacity in chillers ranges from as little as 1.75 kW for air cooled chillers up to several MW for water cooled chillers. Different capacity chillers are equipped with different compressors. Typically, process chillers have a lower COP because these chillers need to generate lower temperatures.


Subsector Chillers
Typical application AC chillers to cool whole buildings, process chillers for industrial processes (the information on this page focuses on AC chillers)
Typical end-users Mainly office buildings, retail sector, but also the health sector (e.g. hospitals), leisure and hotel sector
Main refrigerants used HFC-134a, HFC-410a, HFC-407c, HCFC-22
Natural refrigerant alternative HC-290 (propane), HC-1270 (propene), R-717 (ammonia), R-744 (CO2)
Growth rate / future demand Continuously growing market, especially in emerging economies such as China and India

Scope of improvement: direct emissions

  • Switch to natural refrigerants
  • Leakage reduction is especially important with high amounts of refrigerants in larger chillers
  • Reducing end-of-life emissions
  • Reducing overall cooling needs in new building developments

Read more on the scope of improvement: direct emissions

Scope of improvement: energy efficiency

  • Cycle improvements: heat exchanger, inverter compressor, oil-free, magnetic bearings
  • Using HC-290
  • Part-load controls
  • Careful positioning and good maintenance
  • Reducing leakage
  • Reducing overall cooling needs in new building developments

Read more on the scope of improvement: energy efficiency

Study on green cooling technologies

The Green Cooling Technologies Study tracks global market trends of key refrigeration and air conditioning subsectors. For more information, request the full PDF publication here.