Photovoltaic Consultation: 45° Gable Roof North/South

This is the bill for my house as an example.

When was that? Your assumed costs seem very high to me, considering the threads in a specialist forum. EDIT: Additionally, I always wonder with these return calculations when a normal gas heating system and electricity supply without photovoltaic become profitable *lächel*

The house has 240 m2, of which 80 m2 is a separate apartment, and is occupied by 6 adults (3 generations). Built in 2002, so energetically not up to date. Alternative continuing with gas was not an option.

The yield from the north is completely irrelevant. Max it out. The [Sowiesokosten] make purely south-facing occupancy far too expensive compared to if you let everything be covered.

Current example (all in offers) for a system in Stuttgart from 10.04: 7.2kWp south-facing occupancy + 10.2 kWh LFP battery: €15,999 (= €2,222/kWp incl. storage) 13.95kWp south-/north-facing occupancy + aforementioned battery: €19,499 (= €1,398/kWp incl. storage)

I wouldn’t even begin to think about the yield in the north. With the extra cost of €3,500 for 6.75kWp (= €518/kWp), the upgrade always pays off.

I wouldn't even begin to think about how the yield in the North is. For the surcharge of €3,500 for 6.75kWp (= €518/kWp), the upgrade always pays off.

I see it differently, because the yield is what your system actually delivers. The kWp only describes the technically possible peak power of the modules. Assuming a price advantage of solar power over grid electricity of 20ct/kWh, you first have to generate 17,500kWh more solar yield for €3,500 and also use it entirely yourself. This can be worthwhile in a household with a pool heating system. With a typical consumption profile, I do not see an attractive ROI here.

I see it differently, because the yield is what your system delivers to you. The kWp only describe the technically possible peak power of the modules. Assuming a price advantage of solar power over purchased electricity of 20ct/kWh, you first have to generate 17,500kWh more solar yield for €3,500 and also use it completely yourself. This can pay off in a household with a pool heating system. With a typical consumption profile, I do not see an attractive ROI here.

With a pure north orientation in Saarland, this is about 3,700kWh p.a. that can be additionally harvested (if that were the case for the OP). Now you can calculate for yourself what the possible yield is and whether it is worth feeding in and/or consuming 74,000 kWh over 20 years (heat pump, car, etc.). Especially in the mornings and evenings due to the west/east sun, this makes sense (a storage system is available anyway).