Which heating system for the 200 sqm new building?

Photovoltaics pay off through the subsidy

Which subsidy?

There may possibly be additional local subsidies, but I only meant the feed-in tariff over 20 years.

Which subsidy?

Guaranteed feed-in tariff over 20,x years.

You have to actually have the 15,000 euros for a photovoltaic system first ... And without storage, if you don't have air conditioning, I don't know what I would do in the summer with the electricity that I would need in the winter ... and storage systems are still too expensive for us ... With an electric car, then maybe it's worth considering again ... And it's a completely different technical challenge to paint a house than to plan a heating system .... we did a lot ourselves, really, but even we wouldn't have dared to do that ....

I helped with two ring trench collectors. It is definitely not rocket science. The planning was done by a heating engineer who collaborates with Nibe. Otherwise, there is another forum where a lot of help and planning is provided.

And without storage, if you don't have air conditioning, I don't know what to do with the electricity I would need in winter during the summer ..

Sell it. Exactly the electricity in summer is what makes the system economical. Self-consumption is a bonus on top.