In a conventional reciprocating compressor the piston will always be working at full speed when the compressor is on to deliver maximum cooling capacity. Normally the load in the freezer is not high enough to need the maximum cooling capacity so the piston movement is excessive and energy is wasted. An inverter compressor can operate at different speeds depending on the ambient and load conditions. At times when the freezer only needs a minimal amount of cooling due to lower ambient temperatures, such as overnight, the compressor will move at a slower speed using much less energy.
The start up of a compressor is the most energy consuming part of the cycle. The ability of the inverter compressor to run at lower speeds has the advantage that the compressor will not turn off and on as often thus saving energy and reducing wear.