At 10kWp, the price should be around 1300-1400 EUR gross for it to be a reasonable price. Anything else or significantly more expensive is not appropriate.
The question is to what extent the term "appropriate" refers to 2020 or 2021. But unfortunately, first of all, you have to get other providers at all to receive comparison offers.
Do we always calculate the prices including installation?
For us, the installation was done on Friday ;)
... but yes, I mean the prices including installation. In our case, for 11 kWp with scaffolding etc., at 1350 EUR / kWp. Mind you, no "cheap stuff" installed, but proper modules and inverters from German manufacturers.
I am also aware that it can be significantly more expensive. With exceptions, but even cheaper if someone wanted to :)
I mean, there was something good about the individual power optimizers. I don't remember exactly, but I think one provider said that even without shading it can be advantageous...
Basically, they just have to "earn their money". Per kWp, I would calculate with 3 optimizers for 3 modules, an optimizer also costs a considerable amount of money (material at least 50€). That should be taken into account in the calculation.
The question is to what extent the term "appropriate" refers to 2020 or 2021. But unfortunately, you first have to get other providers at all to obtain comparison offers.
In our case 2021. A friend of mine, however, also had his 13 kWp installed at a reasonable price (from another provider) just two months ago. It is clear that nothing is directly comparable 1:1 and also varies regionally. Therefore, I write this only as a "guideline" since there are very wide price ranges, even in the same regions. Some offer it for < 1500 EUR / kWp, others want 2500 EUR / kWp for the same performance. I’ve seen it all.
Basically, they just have to "earn their money". Per kWp I would calculate with 3 optimizers for 3 modules, an optimizer also costs a decent amount of money (material at least 50€). That should be taken into account in the calculation.
Ok, sounds logical, but how much does an inverter cost? Apart from the additional space in the technical room, which I might not have...