ᐅ Lower Saxony provides subsidies for photovoltaic battery storage.

Grobmutant schrieb:

@Golfi90: Why shouldn’t your roof be able to fit 10 kW peak? The roof doesn’t look that small at all.

The house is 9.5 x 9.5 m (31 x 31 ft) wide with a 60 cm (24 inch) roof overhang.
The vertical distance from the eaves to the ridge is 2.5 m (8.2 ft) with a 28° roof pitch.

I’m not sure if you can use this information to estimate what might fit on this roof.

Grobmutant schrieb:

@kati1337 You would need to increase to at least 8.55 kWp, otherwise there is no subsidy.

The system can probably be expanded by any other solar installer. Why wouldn’t that be possible? Find a good solar installer and check with them what your current inverter could handle. Buying a new inverter just for an additional 4 kW doesn’t seem economical to me.

We have a Kostal Plenticore Plus 4.2 kW (kilowatts), I believe it can’t handle more than our current system capacity (?).
Why would I need to go up to 8.55 kWp for the subsidy? I thought a battery would also be subsidized if you add it to a system with more than 4 kWp already installed?
Edit: I read the excerpt properly again, now I understand why. Okay, then I would need to check if 8.55 fits.

Golfi90 schrieb:

Did you also cover your north side, etc.?
Or how is your system divided?

Are you asking me? We have a hip roof, where a triangular section (see avatar) faces south with a slight east lean. There are 6 modules installed there. On the west side (which is logically tilted slightly toward the south), there are 18 modules. The east side could have fit 18 modules as well, but that area was completely shaded because of large oak trees standing there (they were cut down the following year :rolleyes). The north side only allowed for 6 modules, which wasn’t worthwhile in terms of yield.
Now that the oaks have been removed, I would like to install panels on the east side as well. However, I would need a new inverter for that...

@seth0487 What is the total area of your roof? Or rather, the eave length?

@Golfi90 I can't give you an exact answer, but here are some pictures of the installation:

Golfi90 schrieb:

I don’t think I’ll exceed 10 kWp anyway... so this subsidy probably won’t apply to me...

About 5 kWp would be enough for me, plus a storage system. And then a wallbox.

Combining all that with the Bafa subsidy would be great!

Is that enough? Or is there no more space on the roof?
The ratio between the generator and battery storage should be about 2:1, so approximately 2.5 kWh of battery storage for 5 kWp.
However, the battery will then run out faster than you can blink.

Just my humble opinion: install as much as reasonably fits. Start with a small battery (modular)
and possibly expand to a usable size later if subsidies improve or prices drop.