Different statements from Gu / Gü about the topic of heating

Yes, depending on the soil that is probably possible. But it depends on a few circumstances. Usage restrictions possibly in the area of sealing. Otherwise, I don't know any.

- Geothermal energy: Actually the "best" option, but due to high costs for deep drilling usually financially the most expensive. If interested and skilled, building a trench collector yourself is also cost-optimal.

Gas was not an option for us because there is no gas pipeline available.

On the difference between air-water heat pump and geothermal heat pump:

The pure heat pump for geothermal energy costs comparably to an air-water heat pump.

However, the entire outdoor unit is omitted.

That saves money.

The borehole is expensive, in our case about €10,000.

BUT:
There is BAFA funding of €5,000 if the heat pump is Smart Grid Ready.

Additionally, you save the outdoor unit (€3,000?).

You also save the construction work for the foundation for the outdoor unit and the trench between the outdoor unit and the heating center, so in my opinion we are roughly cost-neutral. Our borehole is located directly under the floor slab in the heating room, i.e. no pipe trench outside.

In terms of consumption, the geothermal heat pump is cheaper because in deep winter it has a supply temperature of about 10°C compared to the air temperatures, which are often around 0°C.

Then there are the noises of the outdoor unit noticeable during normal operation. And when the outdoor unit defrosts regularly, you can hear the rattling clearly. That would have bothered us.

By the way, BAFA funding is also available for trench collectors. Therefore, it is really very attractive compared to the costs of the borehole.

Best regards

Ekki

Sorry, I must have confused it with the flat collectors. There are many more ... ("Leitfaden zur Nutzung von Erdwärme mit Erdwärmekollektoren" would be great if you could link directly to it on the internet ...). Therefore, I take everything back and claim the opposite!

Oh, one more small addition. My acquaintance has built about 200 sqm KFW 55. He has a heating load of 5.5KW at -12 degrees. Under similar conditions, you will probably have a heating load of 3-4KW. Mind you, at the design temperature. That is almost nothing.

So no matter what you choose, pay attention to a low modulation. That means the heating system can regulate its output as low as possible. That really helps the technology a lot.

The 5.5kw should be without hot water and include [Kontrollierte-Wohnraumlüftung mit Wärmerückgewinnung]. Still, the direction is clear.

Modulating heat pumps are a good thing, but you have to be willing to pay for them. These are the top models; according to my previous research, there is often a €5,000 difference between a standard model and the modulating variant. This cannot be justified by lower consumption. The hope remains for better durability.

Including WW without controlled residential ventilation.. However, the internal gains were taken into account, so calculated according to Passive House. And even in the first winter, there were still problems with solar radiation.

For me, heating load self-calculated, I was still 1KW below the calculated heating load this winter.

Yes, modulating is more expensive. But it can be worthwhile. And if it goes towards trench collectors with own effort, it could be within budget. But here I am speculating too much again. First, there would need to be a bit more input.