What COP actually means
COP stands for Coefficient of Performance. In plain words, it tells you how many units of heat you get out for every one unit of electricity you put in. A COP of 3–4 means: put in 1 unit of electricity, get 3 to 4 units of heat. The rest comes free, from the air.
Geyser vs heat pump, in one number
A standard electric geyser has a COP of about 1 — one unit in, one unit of heat out, nothing extra. A KNAPS heat pump operates at a COP of 3–4. For the same bucket of hot water, that is why the electricity consumed can be dramatically lower.
What affects your COP
COP is not a fixed sticker — it shifts with conditions. Warmer ambient air raises it; very cold air lowers it slightly. A lower target water temperature keeps it high; pushing to very high temperatures reduces it. Good system sizing and installation protect it.
Why it matters to you
COP is the single number that translates directly into your monthly bill. A higher COP means the same hot water for less electricity — month after month, year after year. When you compare water heaters, do not just compare price. Compare COP.