The following was communicated to me today by an energy consultant:
"Heating load calculation:
As suspected, there are already some deficiencies or errors here, which is why this cannot be considered professionally done (attachment).
In particular, the controlled residential ventilation with heat recovery was not taken into account.
Whether further errors regarding building geometry are hidden, I cannot judge.
Heating surface dimensioning:
Here too, some deficiencies. The only positive aspect is the chosen flow temperature, if the heat generator is to be a heat pump.
I have not checked whether the software calculates correctly. Many software programs use the same, incorrect calculation core.
Inactive or limited-function underfloor heating surfaces were not considered.
Pipe network calculation:
Since existing errors “carry over” or multiply, I have not reviewed these.
Modern heat generators usually have an integrated heating circuit pump. Their available residual delivery head is manufacturer- and device-specific. This correlation is missing here.
Geothermal probes:
The probes should be dimensioned according to the actually required extraction energy for heating and hot water, which is not the case here.
Positively, however, borehole grouting and possibly two boreholes are planned. The latter is more economical but also somewhat more expensive.
Before dealing with this in more detail, the actual energy demand for heating and hot water should perhaps first be determined.
Conclusion:
Overall very extensive and sophisticatedly prepared and presented, but unfortunately afflicted with some, partly significant deficiencies."
So this topic will keep me occupied intensively and will probably not be successful without paid support from such a professional who accompanies the process from A to Z.