the coefficient of performance (cop) of a refrigerator is defined as the ratio of
Coefficient of performance The coefficient of performance or COP (sometimes CP or CoP) of a heat pump, refrigerator or air conditioning system is a ratio of useful heating or cooling provided to work required.[1][2] Higher COPs equate to lower operating costs. The COP usually exceeds 1, especially in heat pumps, because, instead of just converting work to heat (which, if 100% efficient, would be a COP_hp of 1), it pumps additional heat from a heat source to where the heat is required. For complete systems, COP calculations should include energy consumption of all power consuming auxiliaries. COP is highly dependent on operating conditions, especially absolute temperature and relative temperature between sink and system, and is often graphed or averaged against expected conditions.[3]
Air quality index Some of the key pollutant densities in Î¼g/m3 for the hourly background index, the corresponding sub-indices, and five CAQI ranges and verbal descriptions are as follows.[33]