COP (Coefficient of Performance)

Discover the meaning and importance of Coefficient of Performance (COP) in heating and cooling systems, and how it affects energy efficiency and energy bills.


The Coefficient of performance is most used to indicate the performance of an HVAC unit when it is in heating mode.

Similar to EER, it is a ratio of inputs vs outputs; if a unit has a COP of 4, that means that for 1kW of electrical input, 4kW of cooling or heating output is generated. The higher the COP ratio, the more efficient the unit is.

However, unlike EER there is greater variance in the indoor and outdoor temperature conditions used to calculate COP, which means that COP data for different pieces of equipment from different manufacturers cannot necessarily be compared fairly.

Like SEER (Seasonal Energy Efficiency Rating) there is also a SCOP (Seasonal Coefficient of Performance) which attempts to provide a fairer means of calculating heating efficiency across different climate conditions or seasons. There are slightly different standards for how this is calculated in different regions and countries.

You may also like

Low-energy heating

Fan Coil Unit (FCU HVAC)

Programmable thermostat 

Damper in HVAC