SCOP (Seasonal COP)
A heat pump's average coefficient of performance over a standardised heating season, weighting test points by how often each outdoor temperature occurs.
SCOP is defined in the European standard EN 14825 and used for ErP energy labelling. Instead of one test condition, it combines performance at several outdoor temperatures (for example -7, 2, 7 and 12 °C), including part-load operation, defrost and standby losses, weighted by a bin distribution of hours for a reference climate: average (Strasbourg), colder (Helsinki) or warmer (Athens).
Annual electricity (kWh) = heat demand (kWh) / SCOP
Example: 12,000 kWh heat / SCOP 3.8 ≈ 3,160 kWh electricity
SCOP is quoted separately for low-temperature (35 °C) and medium-temperature (55 °C) applications. Typical values for air-to-water units in the average climate are 4.0–5.0 at 35 °C and 3.0–3.8 at 55 °C; ground-source units reach 4.5–5.5 at 35 °C. The related seasonal space heating efficiency (ηs) used in EU ecodesign rules is calculated as SCOP divided by a conversion coefficient (2.5 in the original regulations), minus small correction terms.
Field-measured seasonal performance factors (SPF) are often somewhat below lab SCOP; UK and German monitoring campaigns found median air-source SPFs around 2.8–3.5, depending on installation quality and emitter temperatures. For cooling, the equivalent seasonal metric is SEER, defined in W/W in the EU and in BTU/Wh in the US.
Related terms
All terms →- COP (Coefficient of Performance)
The ratio of useful heat (or cooling) delivered by a heat pump to the electrical energy it consumes, measured at a specific operating point.
- SEER
Seasonal Energy Efficiency Ratio: total cooling output over a cooling season divided by electricity used, in BTU/Wh (US) or W/W (EU).
- Heat pump
A device that uses a refrigeration cycle to move heat from a cooler source (air, ground, water) to a warmer sink, delivering 2–5 units of heat per unit of electricity.
- Air-source heat pump
A heat pump that extracts heat from outdoor air, supplying space heating and hot water (air-to-water) or warm air (air-to-air), and the most widely installed type.
- Heating degree days (HDD)
A measure of how much and for how long outdoor temperature falls below a base temperature, used to estimate and normalise building heating demand.