Combination of air source heat pump and water-carrying fireplace

Hard to say, there is no information here about the energy demand. If it is low, there would still be the possibility to heat with electricity. Your P.S. is not so far-fetched. I know someone who operates the heat pump with household electricity, in principle to obtain exclusively green electricity.

We also use household electricity but simply because the meter costs and basic fees exceed the savings of the tariffs.

We also use household electricity, simply because the meter costs and base fee exceed the savings of the tariffs.

That probably also depends on the location. For me, two meters + WpTarif are cheaper.

That probably also depends on the location. For me, two meters + heat pump tariff are cheaper.

But probably only if you use the only provider of heat pump electricity without a basic fee or consume relatively much.
Calculations on this can be found here:

But probably only if you use the only provider of heat pump electricity without a basic fee or consume relatively much. Calculations on this can be found here:

No, I also pay a basic fee for heat pump electricity, but still pay less per year despite low consumption. With an air-to-water heat pump or something with higher consumption, it would be even more worthwhile. By the way, I have used comparison portals. I could save €20 with that if I had a meter AND switched providers every year for a €200 switching bonus, but that can't go on forever anyway (who knows how long the bonuses will last). I will continue to compare, but basically I have no desire to switch every year.

Just a silly question - does Maingau have a heat pump tariff? But we are there with household electricity for both.