The discrepancy you find is about 30 %, and is probably in the range that you have to expect.
The Report on a fair energy label for consumers "CLOSING THE ‘REALITY
GAP’ – ENSURING A
FAIR ENERGY LABEL
FOR CONSUMERS" by CLASP, ECOS, EEB and Topten, 2017 says:
Fridge energy consumption is tested and reported according to a norm (EN
62552:2013) that basically prescribes that the empty fridge is running in steady state (i.e. already cooled down) with an environment temp of 25 °C and defined humidity. I do not have access to the norm, so I don't know the interior temp that is prescribed. The report suggests that it may be 5 °C (but I don't know where in the fridge).
The unrealistic temperature settings are used as surrogate for door opening and cooling of warm food when put into the fridge.
The report gives comparisons for several fridges of these norm values and what they think a more life-like cycle of door opening. 2 out of 10 tested fridges that had negligible (< 1 %) discrepancy between these two test regimes, but 2 others had 26 and 32 % higher energy consumption in the door opening test.
They also briefly describe that they found loading/unloading to have major impact, but that is published as observed temperature and unfortunately not as energy consumption.
In any case they conclude that the current test norm doesn't give good real life energy consumption estimates - it is rather a way to measure and compare insulation properties of the fridge.
Factors related to your lifestyle that may have significant impact your fridges' power consumption.
Recommended temperatures are 7 °C in the fridge and -18 °C in the freezer compartment (see e.g. German Environment Agency (Umweltbundesamt)). (This will result in about 8 °C at the top of the fridge and ≈ 2 °C at the bottom of the open compartment just above the veggie drawers).
1 °C temp difference inside (yours being set to 6 °C) depending on the actual temperature at the back side of the fridge may mean something in the order of magnitude of 10 % difference in the temperature difference the fridge has to produce and thus also in energy consumption.
Similarly, the air temperature at the cooler can vary a lot: where I am, a well ventilated cool pantry may have quite a bit < 20 °C thrughout the year, while a a space in the actual kitchen or living room-kitchen under the countertop with just a few ventilation slots may very well result in > 24 °C during the fridge's work cycle.
I'd measure both fridge temp at the top of the fridge compartment (should be 8 °C for 7 °C setting at the thermostat) and the temperature behind the fridge when it is working hard (freshly filled with not-yet-cool food).
Most of the time almost full: should lower the impact of door opening, but would increase the impact of loading/unloading.
So total impact is difficult to estimate, and will depend on how cool the food is when you put it into the fridge.
Two persons in a shared flat with independent eating habits may produce quite more door opening events than a family of 4 who eat together.
Should I complain?
(Thanks, FarO for digging out the underlying EU directive "energy labelling of household refrigerating appliances".)
This directive says that you can complain if your fridge consumes more than 10 % more energy than specified on the label for the prescribed testing procedure. Finding higher energy consumption during normal household working conditions is not sufficient to say the label is wrong.
- The test indeed uses +5 °C interior temp and +25 °C ambient temperature
which is a higher temperture difference than under your working conditions.
- The test does not require door openings, nor
- cooling down of food you place into the fridge.
The latter 2 points are reasons for higher energy consumption under your working conditions.
So the testing procedure is too far away from normal household use to reliably say that the fridge should not use more energy under household conditions than under the testing procedure/it says on the label.
In order find out whether you have reason to complain about the fridge/product (as opposed to complaining at the EU about unrealistic lab conditions in the prescribed test), you'd need to check energy consumption of your fridge with the prescribed temperature settings under steady-state, empty, door-closed conditions and find that this energy consumption is > 195 kWh/a (1,1 x 177 kWh/a as per label in the linked product page).