Comparison of groundwater / brine / air heat pump

Hello everyone,
I have a new construction coming up (two-story single-family house, approx. 140 m² living space) and I definitely want to use a heat pump for heating. This in combination with a photovoltaic system with a storage battery. I do not want cooling in the house, I only need the heat pump for heating and hot water. The house will not have a ventilation system. I have now received so many different statements regarding the heat pump from various experts that I cannot come to a clear conclusion. Maybe you can help me get started?

I will roughly summarize my collected arguments (pro/contra):

Water-water heat pump

[*]Highest energy yield and efficiency
[*]High acquisition costs due to groundwater drilling
[*]Costs cannot be estimated in advance, depend on groundwater level and soil conditions

Air-water heat pump (recommended to me by the construction manager)

[*]Manageable costs
[*]Low space requirements
[*]Apparently sufficient for the house (I am not sure about that)
[*]The fan is audible (though relatively quiet), which could possibly disturb neighbors or myself

Brine-water heat pump

[*]Longest service life (possibly irrelevant since modern technology is worth it after 10-20 years anyway?)
[*]Low acquisition costs
[*]High space requirements for ground collectors (would not be a problem, garden is large enough)

Based on my layman’s assessment, I would choose the water-water heat pump and accept the additional cost of approx. €10,000. Are there any arguments I have overlooked? What are the long-term experiences (maintenance work, repair and maintenance costs)?

Thanks in advance!

Hot water requires suitable groundwater and a permit from the water authority. There is also always the risk that the system will become clogged due to manganese or similar substances.

SoleWater deep drilling or trench collector.

Air-water heat pump is the easiest to implement and the most affordable, and of course, it can keep a 140 m2 house warm.

As always, my note: MORE IMPORTANT than the heat source is the design of the underfloor heating and its hydraulics.

Investigate groundwater and soil first, it might not even be that expensive. If it is, brine is also fine. Air-water would be my last option from the given choices.

Only the air-to-water heat pump makes economic sense here. The new systems are also very quiet. I would immediately dismiss brine and groundwater, very expensive and partly susceptible (especially groundwater).

For your household appliances, an air-to-water heat pump is ideal anyway. Even better would be a gas connection.

Exactly this question was asked here just 2 weeks ago, but I can't find the post anymore..

Thanks in advance for the answers! I also haven’t found any comparable posts here. The answers here are very contradictory as well. From this, I conclude that the decision is not easy and depends on the conditions. Would you try to commission an independent analysis and consultation? Who is best to contact for that? There are “experts” like sand by the sea.

I still have to deal more intensively with a brine-water heat pump. Specifically, the pros and cons of ground collectors vs. deep drilling with probes.

If I understood correctly, you first have to make a significant upfront investment for a water-water heat pump: test drilling, water analysis, etc. In the end, it might turn out not to be worthwhile. In my opinion, that is the biggest risk. Unfortunately, there is no one in the neighborhood yet who uses a W-W heat pump; otherwise, that would provide a point of reference.

: The suggestion with the gas connection wasn’t serious, was it? :)

The design of the underfloor heating is important, that is clear to me. It has to match the heat pump. Exactly what matters in this regard, I still have to research (tips/links would be appreciated).