Groundwater heat pump experiences?

Hello everyone,

has anyone installed or obtained approval for a groundwater heat pump? Are there any experience reports on this? Can any recommendations be given? It was just recommended to me as an alternative to liquid gas tank/natural gas/air-water heat pump.

Thank you very much for your answers!

Regards,

Leon

Hello,

...has anyone installed or gotten approval for a groundwater heat pump? Are there already any experience values on this? Can any recommendations be made? It was just recommended to me as an alternative to liquefied gas tank/natural gas/air-water heat pump.

Only wood, pellets, and oil burners are missing now ;-)
With a warm water heat pump, if the boundary conditions are right, a higher annual performance factor can usually be achieved compared to, for example, a brine heat pump, since the source temperature is higher. Despite the higher energy expenditure of the source pump.
However, it particularly depends on the water quality and the performance of the extraction well (subsoil, groundwater level). Well-suited locations are, for example, river valleys. Here, too, approval from the lower water authority is required. If sufficient water quality is not observed, extraction and/or injection wells tend to clog quite early, e.g., with iron deposits. Then it looks rather bad.
Basically, heat pumps require special boundary conditions that must be ensured. With insufficient or missing planning, it can quickly become a money pit.

The higher the actual demand (power, energy) for heating and hot water, the more important a high annual performance factor is (moderately to well-insulated buildings, cold climate locations). For very well-insulated buildings and mild locations, one can save the considerable effort of source development and rather fall back on an air heat pump.
Natural gas is also an option, but consumption (kWh) is higher than demand; with heat pumps, it is the other way around. Gas condensing units are usually inexpensive to purchase; however, one must not forget the sometimes rather hefty connection costs.
Liquefied gas is not necessarily a favorite because the energy carrier price is sometimes significantly higher compared to, for example, natural gas. Also, the low modulation values (minimum output) are not achieved.

Best regards

Not that I understood much of it... but still, thanks for the massive text. What I could gather is that without optimal conditions, I have to pay quite a lot for it, which in turn (in my opinion) implies that I am better off with an air heat pump + solar for water + wood stove.

..., which in turn (in my opinion) implies that I am better off with an air heat pump + solar for water + wood stove.

A wishful thinking that does not automatically prove to be economical. A conglomerate of weekend with partly competing requirements rarely leads to a meaningful system effort ratio. The additional investment or capital service for this is usually in a less favorable ratio to the benefit. In many cases, the concept is not even sensibly mastered with a weekend, let alone a collection of various components. Technically, almost everything can be linked, but unfortunately this often does not make much sense.

Okay, so what should I do now? Does my architect calculate the energy consumption and thus the most cost-effective heating method? Or should an energy consultant be brought in? Something different and honestly: Is anything actually more worthwhile than Kfw 70? I mean, of course, for the green conscience and all... but measurable in numbers with an associated amortization of the costs over the next 20-30 years? Thanks for your answers!

Okay, so what should I best do now? Does my architect calculate the energy consumption and thus the most cost-effective heating method? Or should an energy consultant be involved?

Both are hardly likely to achieve the goal. Neither architects nor energy consultants have training in building services engineering (TGA). These deficiencies have been partly recognized. Some universities of applied sciences now additionally expand the training of their civil engineers with the field of building services engineering, at least partially and in the basics. To what extent this will bear fruit in practice remains to be seen in the future. If you want to be certain, you should bring a specialist on board who is familiar with small units, a TGA planner, energy consultant, and for example a civil engineer all in one person. For questions, feel free to contact me by email or private message.

...Something different and hand on heart: Does anything really pay off better than KfW 70 at all?

The question is completely justified, but hardly answerable with reliable numbers for the individual case without object-specific data. The fact is that many run after “alleged grant gifts” ;-) What is forgotten here: Who is giving away something! ;-) Subsidies impose conditions that initially always require increased investments (capital service for this) ;-) Often the consumption costs that are "beautified" on paper are actually not achieved! How terrible, since quite high initial investments were made! Theoretically "beautified" evidence, e.g. KfW certificates, are by no means a guarantee for the operator's profitability in detail. As I also work as an expert, I could write a book about defrauded builders ;-)

...So clearly, for the green conscience ...

That is usually only discovered afterward when one's own profitability has more or less gone down the drain ;-)
Best regards