Heating system for our single-family house!

Quick question for understanding: does solar also support the heating? Or is it only used to heat the water? Is the heat from summer stored somehow to be used in winter?

The solar system heats water. This is stored in the 300-liter tank until it is used during the day/evening. If more is consumed, the heating system switches on.
Nothing is stored from summer to winter, of course. The sun also shines in winter, so the water is heated then as well.
If you have no idea about the air-water heat pump and all that, you should take a solid gas heating system. That’s what we did.
Additionally, a nice fireplace for radiant heat in winter, but it costs more than it’s worth. Like the solar gimmick – you save something... at least on expensive heating technology required by the energy saving regulation. However, we also needed a controlled residential ventilation system with heat recovery.
For an energy saving regulation: many roads lead to Rome: better insulation, controlled residential ventilation, triple glazing, air-water heat pump, solar, photovoltaics... something has to be renewable. I can’t say anything about water-bearing fireplaces.

If you have no idea about air-water heat pumps and all that, you should get a solid gas heating system.

I find that argument a bit weak, because who really knows about gas heating systems?

IMHO it would be helpful to specify what "nice warm shower" means. For some, 39 °C is enough, others need 45 °C. We here manage well with the Rotex HPSU Compact, but I admit the temperature of the shower/bath water from the tap should not be lower than the default setting.

About the price: Is the gas connection already installed? If not, the air-water heat pump is cheaper. If yes, you would have to renegotiate to make the air-water heat pump cheaper. Then you have an additional aspect for decision-making :P.

We had also considered a water-bearing fireplace. The result was that it will probably never be worthwhile.

Are they really that expensive?

Either you need your water or it is warmed for free.
K.

That sucks :(

If the house is really planned so well that the hot water pipes are quite short, you could do without it.

Do you mean that the utility room and the bathrooms should be on top of each other?

Are you getting a ventilation system?

No

IMHO it would be helpful to specify "shower at a nice warm temperature." For some 39 °C is enough, others need 45 °C.

45 preferably :)

Regarding the price: Is the gas connection already included?

In the house price? Connections like gas, electricity, and water are not. We already paid for the gas connection in the development costs for the street.

Are they really that expensive?
Do you mean that the utility room and the bathrooms should be on top of each other?
.

Ideally, yes. That doesn’t just affect the circulation pipes. Other water/sewage pipes are also shorter and therefore cheaper.

But I didn’t pay any attention to that when planning the house. Only the practical feasibility was important to me.
I’d rather have a floor plan that suits and pleases me than one where the wet rooms are stacked/next to each other but the rest of the house doesn’t fit.
We have 2 bathrooms, a guest toilet, kitchen, and utility room. None of that is together or on top of each other ;)

Have already paid for the gas connection in the street development costs.

The gas connection must run all the way to the gas condensing boiler, that should be clear and must be paid for. Only you can know the details. For the air-water heat pump, you only need electricity, and you have that anyway.

At 45 °C, gas could be the better choice. The hotter the water needs to be, the less efficient the heat pump becomes. Combustion has no problems with that. In detail, it then becomes a calculation exercise with many unknown variables (electricity price? gas price?). Then you can just let your feeling decide ... ;-)

Included in the house price? Connections such as gas, electricity, and water are not included. We have already paid for the gas connection in the street development costs.

Are you sure that this also covers the costs on your own property? To me, that sounds more like the public development, and the installation on your property will be an additional cost on top.