Compressors: key trends

Over the past few years, the design and performance of rotary, reciprocating positive displacement and dynamic compressors have been greatly improved. CO2 compressors have conquered new niches and twin-screw compressors are now increasingly used in truck and bus systems. Single-screw compressors have secured a good market share, particularly in large ammonia plants, and progress has been achieved in the application of mixed refrigerant cycles and variable-speed systems. Rotary models are also increasing rapidly in air-conditioning applications. The global compressors market is expected to grow over 8% over the period 2004-2006, with greatest expansion occurring in Asia and Europe. Sanyo is the biggest supplier of CO2 compressors (20 000 since 2001) used in heat pumps applied in water-heating applications and intends to produce CO2 compressors for refrigerated display cabinets on a large scale. Danfoss, Tecumseh, Dorin, Modine and Bock are producing CO2 models used in a wide range of applications: display cabinets, vehicles and commercial refrigeration. Air and water cycles are attracting growing attention.