There are basically four different types of compressors used in vapor compression chillers: Reciprocating compression, scroll compression, screw-driven compression, and centrifugal compression are all mechanical machines that can be powered by electric motors, steam, or gas turbines. They produce their cooling effect via the "reverse-Rankine" cycle, also known as 'vapor-compression'. With evaporative cooling heat rejection, their coefficients-of-performance (COPs) are very high; typically 4.0 or more.

In recent years, application of Variable Speed Drive (VSD) technology has increased efficiencies of vapor compression chillers. The first VSD was applied to centrifugal compressor chillers in the late 1970s and has become the norm as the cost of energy has increased. Now, VSDs are being applied to rotary screw and scroll technology compressors.