KFW55 funding + BAFA funding

A brine heat pump including installation plus deep drilling for under 13,000€? Respect, I have never been offered that anywhere.

Well, deep drilling naturally costs more, that's true. I just had the heat pump plus horizontal trench collector as a DIY project in mind.

But what if I build kfw 55 in conjunction with an eligible geothermal heat pump? Until last year, in addition to the 4500€, there was also 50 percent of that through the kfw 55 standard. I can't find anything about that now.

The 50% grant for the KFW55 standard applied only to existing buildings, not to new buildings.

Does anyone have an idea what the point from the information sheet for "Smart Home Systems" (specifically KNX systems) concretely means?

If you integrate the heating control into KNX (or other systems), then that counts as the "heating system". The same applies to ERR, which can also be KNX operating elements with room temperature controller function. It is also stated in the information sheet that these can be visualizations, for example, if room temperatures or the heating control can be viewed and controlled through them. Whether this also applies to the 5T€-Visu would at least be interesting.

Ok. Let's assume I plan to build a KNX system that includes not only heating control but also lighting control, control of the blinds, ventilation, and the intercom. Can one then estimate what percentage of the system can be considered eligible costs for funding? Apart from the special components such as sensors, controllers, and actuators, I cannot really distinguish that, or can I?