Imagine you buy a car. The dealer says: “30 mpg — really economical!” You drive it and you get 14 mpg. Cheated? Not necessarily. The 30 mpg figure was correct — measured on a flat motorway in still air at 50 mph on cruise control. But it said nothing about your driving style, your commute, your winter traffic. The same thing happens with virtually every heat pump you buy today.
What SCOP actually is — and what it isn't
SCOP stands for Seasonal Coefficient of Performance. It is the average amount of heat (in kWh) a heat pump delivers over a full heating season per kWh of electricity it consumes. SCOP 4 means: 1 kWh in, 4 kWh out. The catch: “over a full heating season” depends on four parameters the manufacturer gets to choose:
- Climate zone — EN 14825 distinguishes warm (Athens), temperate (Strasbourg, Netherlands) and cold (Helsinki). A manufacturer posting SCOP 5.5 on the poster usually quietly picks the warm profile.
- Water-outlet temperature — 35 °C for underfloor heating, 55 °C for radiators. Efficiency difference: easily 30 %.
- Capacity modulation — full load, part load or a mix? The standard forces a mix, but the weights shift per zone.
- Auxiliary energy — pump consumption in the heating circuit and any backup resistor are weighted in SCOP, but not in COP.
What is a comparable yardstick then? One word: test point. Always compare the same combination of climate zone and flow temperature.
Why Daikin chooses transparency
Daikin NL publishes per SKU the nominal heating capacity at -10 °C ambient — a proven winter-performance figure instead of an efficiency claim chosen for marketing reasons. EPREL, the EU product database, holds the cold-climate SCOP if you want to look it up.
The five-question test before you sign
- At which climate zone is the SCOP measured? (Warm, temperate or cold.)
- At which flow temperature? (35 °C, 45 °C or 55 °C.)
- What is the nominal capacity at -10 °C ambient?
- Where can I find the same model on EPREL?
- Is there a second test point published? (One number is a brochure; two is a spec sheet.)
FAQ
Why does SCOP vary so much between test points?
SCOP is measured over an entire heating season. At 35 °C flow (underfloor heating, mild climate) the compressor barely works — almost every heat pump hits 4.5-5.2 there. At 55 °C flow in a cold climate the compressor works much harder; SCOP often drops below 3.0. The difference between the two test points is literally the difference between 'glossy brochure' and 'realistic winter'.
What is the difference between SCOP and ηs (eta-s)?
ηs (seasonal efficiency, in %) is what appears on the ErP energy label — derived from SCOP minus corrections for control losses and auxiliary power. SCOP is the 'bare' coefficient. For the label: ηs ≈ SCOP/2.5 - 3 % (simplified). Always compare SCOP with SCOP, or ηs with ηs — never cross.
Which test point should I use to estimate my annual consumption?
The standardized EN 14825 main test point is temperate climate at 35 °C flow (mild_35) — the Netherlands sits in the 'temperate' zone, so this is the right anchor for almost everyone. For radiator homes the ErP label also reports ηs / SCOP at 55 °C flow; that figure typically lies 25–30 % lower. For a cold-anchor use the per-SKU nominal heating capacity at -10 °C ambient (Daikin publishes this per SKU; compare against the datasheet of your other candidate).
Can a manufacturer just post A7/W35 as 'COP'?
Yes, and they do. A7/W35 = 7 °C ambient air, 35 °C water — an ideal point where almost every heat pump hits 5+. It is not a lie, but it is misleading: it tells you nothing about your winter consumption. Always ask for SCOP per test point or the ηs on the ErP label.
Why does Daikin not publish cold-climate SCOP W55 in the NL catalog?
EU manufacturers publish standard only for the climate zone in which they sell. Daikin NL chooses 'temperate climate' because that correctly describes the Netherlands. Instead of cold-climate SCOP, Daikin publishes per SKU the nominal heating capacity at -10 °C ambient — proven winter performance instead of an efficiency claim. Cold-climate SCOP is available in the EU EPREL product database — it is public and free.
Can I measure SCOP myself?
Indirectly yes: meter your heat-pump kWh consumption (heat-pump circuit, optionally via a P1 meter or smart group) and divide your net heating demand by the electricity consumption over an entire season. That is the SPF (Seasonal Performance Factor). Expect SPF 10-15 % lower than SCOP because auxiliary power and the heating-circuit pump are also counted.
Read the Dutch original (with full per-SKU SCOP comparison table) at /kennisbank/scop-eerlijke-specs.