Gas boiler efficiency and solar thermal energy in new buildings, what are the advantages?

Hello everyone, does it make sense to combine gas condensing boilers and solar thermal energy in a new building? Our developer always raves about an air-to-air heat pump. From my physical understanding, this seems to me to be inefficient. He argues with a sudden advancement in technology in the last two years. A KFW-70 house is planned. Many thanks for the answers.

does it make sense to combine gas condensing boilers and solar thermal systems in a new building

Solar thermal only makes sense if you absolutely need it to achieve Kfw70... Often it is a loss-making business, especially if you have to finance the whole thing...

Air-to-air heat pumps are of course not the most efficient type of heat pumps... It depends on the specific model, its coefficient of performance, and your heating demand... often the COPs advertised in marketing are by far not achieved... Furthermore, it also depends on what your electricity provider charges...

Air-to-air heat pump is a matter of belief. For me, such a thing would never be an option. But I also want radiators and not underfloor heating.

As far as I know, for Kfw 70 you can also use better insulation instead of the solar system.... but a professional can answer that better for you :D

With these heating topics, I am always happy that there is [Fernwärme] at our building site ^^

Hello,

With these heating topics, I am always happy that there is district heating at our building site ^^

And especially district heating is something that would be too unpredictable for me ;)

Kind regards

...does it make sense to combine gas condensing boilers and solar thermal energy in a new building?

One option among many others. Virtually the most commonly chosen and convenient standard model by general contractors/developers. However, solar thermal systems are usually not economically viable in single-family homes.

...Our developer always raves about an air-to-air heat pump. ....A KFW-70 house is planned.

That will most likely be a money pit ;-) Best regards