Heating and ventilation system KFW40 house

Hello,
my name is Alex and I am currently planning a Kfw40 house (approx. 190sqm) with my family (wife and child).
My personal problem concerns the hot water, heating, and ventilation system; here I want to do everything right if possible.
My wish would be a photovoltaic + a solar thermal system, is this still up-to-date?
Which combinations are possible/useful (heat pump, solar, air-to-air heat exchanger ...). As already mentioned :-) .. I have lost track of what makes sense.
I hope you can advise me and help/support me with this.

Thank you in advance,
Kind regards
Alex

I want to put it this way. Whoever heats with gas also heats their hot water with it. So solar thermal is suitable as a relief. Saves gas. Whoever heats with any type of heat pump heats with electricity. Because a compressor always has to be driven. These things basically work like air conditioners, only reversed. Producing your own electricity fits as a relief for that. Photovoltaics. Karsten

Hello Nordlys,
thank you for your reply. Which of the two is recommended? Heat pump or gas?

Best regards
Alex

KFW40

Is almost impossible in combination with a gas boiler.

Caspar is probably right. Because gas is a fossil fuel that does not regenerate and produces CO two. As such, it adversely affects the calculation of the energy certificate according to Kfw and would have to be compensated with extremely high insulation and extremely good windows. We are not questioning the purpose of this calculation here. It is just the way it is. Karsten

Hello Karsten and Caspar, thanks for your answers. It looks like it will probably have to be a heat pump? Something like that in combination with the ventilation system + solar? Or do you have other suggestions/ideas? Which systems can you recommend to me? Best regards Alex