Heat pumps: COP and SCOP explained

The terms COP and SCOP are often used when talking about heat pumps and so we thought we would take a moment to explain exactly what they mean and why they are important.

What is COP?

In simple terms, the coefficient of performance (COP) of a heat pump compares the energy coming out to the energy going in A COP of 4 shows that for every 1kw of electricity your heat pump uses, will output 4kw of heat to warm your home or hot water.

What is SCOP?

The seasonal coefficient of performance (SCOP) refers to the seasonal average. Given our varied British weather, SCOP is important because COP may only show the best-case scenario. For example, an air source heat pump running on a mild day outputting low heat to a well-insulated home would show a COP of 5 or more but when winter temperatures plummet, it may show 2.5.

Why do we have SCOP?

SCOP is a rating that makes a clearer and more fair comparison for homeowners. Before when just the COP was given, some heat pumps were mis-sold. With today’s current high electricity prices, it is sometimes not cost effective to install a heat pump and we want to be transparent about this to our customers. A heat pump is not right for every home or business.

What can influence COP and SCOP?

The design. Understanding the relationship between insulation, heat loss of the building, pipe and emitter sizing all enable a low temperature system design.

Our team are experts in COP and SCOP. More information here.