Is the surcharge for an air-to-water heat pump justified compared to gas?

Sorry, but personally I wouldn't bet on gas anymore. With good design, you might use about 2500-3000 kWh of electricity for heating energy.

That's how we saw it too and decided on an air heat pump. My annual consumption last year was 2099 kWh for heating and 535 kWh for hot water supply. Based on today's knowledge, I wouldn't choose gas anymore. But I also find the additional cost too high. Our construction company offered both. And without extra charge. ;)

that's how we saw it too and decided on an air heat pump. My annual consumption last year was 2099 kWh for heating and 535 kWh for hot water supply. Based on current knowledge, I would no longer go for gas. But I also find the surcharge too high.
Our construction company offered both. And that without extra charge. ;)

It's not just about consumption, as already mentioned. It’s about the total costs.

It's not just about consumption, as already mentioned. It's about the total costs.

Which was mentioned in the case of your previous poster. No extra charge for the heat pump, plus the elimination of the gas connection. So ultimately saved. And that led to low monthly costs.
Anyone can afford that. I would not accept such a huge surcharge as with the OP. You might as well take the gas boiler, buy and install a Panasonic air-to-water heat pump yourself, and then immediately sell the overwhelming 2.5 sqm solar plus heating again. I wouldn't even have the gas connection installed.