Separate meter and electricity tariff for air-to-water heat pump sensible?

At that time, we insisted on installing only one meter and running the air-water heat pump on the household electricity. A second meter would not have been worth it anyway because of the basic fee. But since the photovoltaic system was already planned back then, we wanted only one meter. Meanwhile, the photovoltaic system has been in operation for a year, and we have had electricity costs of a total of €240 over the past year. With €20 per month for household electricity and heating, we can live very well :D

P.S. The heating works well with the circuits (which were not laid so close together everywhere). The screed has now been heated dry.

We insisted back then on installing only one meter and running the air-water heat pump on the household electricity. A second meter wouldn't have been worthwhile anyway because of the basic fee. But since the photovoltaic system was already planned at that time, we only wanted one meter. Meanwhile, the photovoltaic system has been in operation for a year and we had electricity costs of a total of €240 over the past year. We can live very well with the €20 per month for household electricity and heating :D

That sounds decent. From when does one recover the investment costs of the photovoltaic system?

We currently assume a payback period of the costs after about 10 years. If electricity costs continue to rise, then sooner.

I have now tried to do some calculations, etc. If I also run the heat pump through the household meter, I would be about €400 more expensive per year (without photovoltaic). There is a 12 cent/kWh difference in the tariffs. Therefore, I think it's best to start with 2 meters and photovoltaic and see how it develops. Currently, I am still with the local provider. Is it possible to switch differently there? That is, to get household electricity from somewhere else and keep the heat pump electricity there? Who would pay the feed-in tariff in this case? The solar installer said that the photovoltaic electricity could also be used for both meters. That would be called a power to heat circuit. So, as already mentioned here, that would work with a slight additional effort from the electrician.

There is a 12 cent/kWh difference in the tariffs.

That is quite a lot. What kind of tariff do you have for your regular household electricity? Maybe it would make sense to simply switch the provider there.

Currently I am still with the local provider. Can you switch differently there as well? Like getting household electricity from somewhere else and keeping the heat pump electricity there? Who would pay the feed-in tariff in this case?

The feed-in tariff is always paid by the grid operator, so it has nothing to do with your electricity provider.