We are still quite a way off from that. However, we are slowly approaching the transition period in which there will be no more shading, so that the sun regulates it.
10 to 16 degrees. For me, it's a mix of desired warm indoor temperatures, rather little sunshine the day before yesterday, a lot of wind, and a property that didn't allow a true south-facing orientation of the house. And KFW 55 was only just barely achieved. So I start heating a bit earlier than others. When you put the heating costs in relation to other expenses, they are also very manageable. The heating engineer actually wants 400 euros per year for a maintenance contract (heat pump, hot water storage, controlled residential ventilation). Unnecessary and pure rip-off, but I might not get around it because of the warranty...
The same weather as here. Max. 1-2 hours of sun per day, otherwise just rain for days. So far, the little sun combined with cooking, showering, etc. is enough to keep the temperature at 21-23 degrees. But we are also all at home all day right now. From Wednesday there will be sun again fortunately. In August I wouldn't have heated on principle yet ;)
Unnecessary and pure rip-off, but I might not be able to avoid it because of the warranty...
The same at Stiebel Eltron. Luckily, we don't have to bite into the bitter apple for long.
Average temperature currently at 10.6 degrees, but the heating stayed off last night. Temperature in the house is between 22.5-23.3 degrees. Heating is set to automatic, heating limit 14 degrees.