Gas without solar possible for new construction?

Offer includes Tecalor THZ 504 air heat pump (combined unit with controlled residential ventilation)

I just looked roughly: It has 8 kW? That would be too much for a new build. Half would be sufficient. And if a controlled residential ventilation is included, you can subtract another 15,000 from the price. You need that separately anyway with gas. And all of this has nothing to do with "being cost-effective". Nobody knows if there will still be enough gas next winter. This is all on very thin ice right now. So forget the ecological nonsense, think of the children, and go with your heating technician to look for a heat pump that matches the heating load. You are right about the ERR - you can omit those with gas as well. But rather not the buffer.

Break down your cost comparison clearly. There is surely a snag somewhere

And if there is a controlled residential ventilation system included, you can deduct another €15,000 from the price. You need that separately with gas as well.

I had taken into account the additional costs for controlled residential ventilation with gas.

Option 1
Air heat pump + controlled residential ventilation: Tecalor THZ 504 +€36,800 (compared to gas)

Option 2
Gas: Wolf CSZ (incl.)
Controlled residential ventilation: Tecalor TVZ 180: +€17,600

Calculation (current prices according to Check24 today):
- Heat amount = 12,000 kWh per year
- Gas: ~€1,800 per year
- Electricity (annual performance factor: 4): 12,000 kWh / 4 = 3,000 kWh => €1,214
- Difference: €586 per year

How do you come to a demand of 12,000 kWh? The house should be around 4000 kWh for heating as a KfW40. You will hardly reach 8000 kWh for hot water, it would be more like 2500?

What about the option of taking two devices instead of one expensive device?

I had taken into account the additional costs for controlled residential ventilation with gas.

Then the prices are just crazy. Sorry.
And what if you just have two heating pipes laid in front of the house and then connect a Pana yourself? There are plenty of instructions, it’s not difficult. It would then be roughly the same price as the gas heating.
I know, it’s effort. But for €15,000, the hourly wage could be great. :-)

How do you come up with a demand of 12,000 kWh? The house should be around 4,000 kWh heat as a KfW40. You will hardly reach 8,000 kWh for hot water, it would be more like 2,500, right?

Do you mean 4,000 kWh gas (and therefore 1,000 kWh electricity)? That would be too low, wouldn't it? I just checked the heat pump consumption database again. Sure, there are people who consume less. In the end, though, it doesn’t make much difference (gas consumption would then also be lower).

Then the prices are just crazy. Sorry. And what if you simply have two heating pipes laid in front of the house and then connect a Pana yourself? There are plenty of instructions; it’s not difficult. It would then be roughly the same price as the gas heating. I know, it’s effort. But for €15,000 the hourly wage can be great. :)

My plan is to start with gas first but have everything prepared for a heat pump (underfloor heating designed for low flow temperature). The nonsense is that new buildings receive no subsidy, but existing buildings do when switching from gas to heat pump. I know it’s stupid, but €20,000 is no small change for us (especially since construction prices in general are currently skyrocketing).