LWW, gas or geothermal operating cost experiences

Now comes the gas technician. The much-criticized chimney sweep comes for exhaust measurement once every two years. Because there is nothing to sweep with a gas condensing boiler. Annual costs therefore under 40,- gross. The gas condensing boiler, together with heating support from solar thermal energy, is still the cheapest heating system today; with proper planning and underfloor heating, it enables heating costs of 600,- per year for around 100 sqm of space. It is durable, low-maintenance, the one-time payable gas connection costs around 1000,-. Depending on the region, this may be halved through welcome offers from the gas supplier, the Telekom house connection principle, without a contract 800. With 400. The space required in the utility room is considerably less than with heat pumps, as is the electricity consumption. Provided an unshaded south-facing roof, 65% of the hot water can be produced with solar panels. Economically, gas plus solar is therefore by no means dead.

That's why I said gas or air-water heat pump, depending on some other factors, but not necessarily consumption, which is very good for all heating systems if they are properly adjusted. In our case, the gas connection would have cost around 2300.-, so then an air-water heat pump.

As far as I know (but I am not fully informed yet, because we are not that far along), you do not get KfW55 funding (or better) with fossil fuels but at most KfW70. That should possibly be taken into account. But, as I said, I am also happy to be corrected.

With geothermal energy, there is no visible outdoor unit (just like with gas). If gas is ultimately cheaper to purchase than the air-water heat pump, I would choose gas.

With air-to-water heat pumps, the location of the outdoor unit should be carefully chosen to avoid later conflicts with neighbors due to noise. However, quite a bit has already been written about this here.

...or have in the basement...