In the south of the Peloponnese we noticed it at some point - we haven't had any shore power for four weeks!
The many electrical consumers already need a lot of power - from the 12 volt battery. Pumps for the running water supply, lighting, navigation instrument display - and of course the refrigerator, the biggest consumer of electricity (besides the hot water boiler, but you don't need that anyway at 35 degrees outside temperature).
In addition to the separate starter battery, there are two service batteries that operate the system, with a total capacity of 670 ampere hours. When the engine is running, it charges the batteries of course. And when we are in port and have shore power, the batteries are charged via the permanently installed computer-controlled charger on board. If not, we have four solar panels that we can fold up so that they are optimally aligned with the sun.
This means that if we are lying at anchor and have the fridge on during the day to have cool white wine in the evening, the system loses about 2 percent. If we then fold up the panels the next morning - and the sun is shining - it takes an hour or two to get back to 100 percent. One should not underestimate solar power!
That's why we didn't even notice the four weeks without shore power - we are curious to see how it will be in autumn with less sun.