Energy meter in a heat pump: how to measure consumption and actual efficiency

To know how efficiently a heat pump is operating, it is necessary to measure both the electrical consumption and the generated heat.

Electrical consumption

It is recorded with an energy meter in kWh.

Thermal energy

It is calculated from the water flow rate and the supply-return temperature difference, when suitable sensors are present.

COP

The instantaneous COP is the ratio of thermal power to electrical power.

SCOP

For a meaningful overview, efficiency is examined over a longer period, not just as a single instantaneous measurement.