Collaboration of air-water heat pump, photovoltaic system, and storage

Maybe take a look at your shadow management, it might cost some yield in winter.

I also have quite a bit of shadow due to the low sun and trees. 25% of the modules are not facing south, they produce significantly less in winter. The weather in southern Germany at comparison systems was also much better than here. The most yield comes anyway in summer..

Overall, I am also satisfied. It was almost 6000 kWh in 2019. Return before taxes of 8.5% if it had been fully fed in.

Your yields sound very good!

I agree. For us, it's 87 kWh for the whole of December, a maximum of 6.8 per day (Dec 5), but we only have 6.3 kWp with south and west roofs; the west roof is very poor in December. Of the 87 kWh, we directly consumed 71. With a total household consumption of 758 kWh, the 16 kWh that would have gone into storage are not relevant.
It really depends heavily on how the photovoltaic system is designed. We tried to schedule the hot water preparation during sunshine hours and also to get a bit more temperature into the storage. In winter, even with sunshine, we don’t manage to reach 1.8 kW for the hot water program to be powered directly from photovoltaic electricity.

: Great return. Everything done right and apparently still room for improvement. Shadow management is a good tip from . My system pays off a bit later than yours but has no problems with shadows - it would only be the two slim chimneys anyway. The modules themselves are built internally in parallel with 2Bus cells. The photovoltaic tiles are all connected in parallel. Maybe this is a reason for a comparatively good yield. The roofs face south with maybe 15 degrees toward the east. The left roof has 2 strips of photovoltaic tiles, the right roof a larger area. The arrows help to identify.
[ATTACH alt="8A9B9D9D-EFB7-4DDD-BD62-90234E753768.jpeg" type="full"]41355[/ATTACH].

: To figure out which system fits, you can put together your heavy consumers and see when they run. If you have "outliers" in there (sauna, kiln for ceramics, whirlpool/pool, powerful servers, heat pump, vehicle charging station, tools, air conditioning, infrared panels...) that is relevant for your calculation. That is actually a good start before making a technical decision.

Hello everyone,

Thank you very much for your numerous information and suggestions!

Even if this is slightly "off topic":

I came across the Bafa subsidy for the first time in connection with the air-to-water heat pump.

Air-to-water heat pumps that achieve an annual performance factor of at least 4.5 are subsidized.
Does the photovoltaic system help in achieving this annual performance factor?

The heating engineer would then have to take this into account in his calculation, right? And if so, are the costs of the photovoltaic system also eligible for funding in this context?

Best regards

The annual performance factor refers only to the heat pump. For an annual performance factor of 4, a heat pump must generate 10000kWh of heat from 2500kWh of electricity. The source of the electricity is not relevant for this.