Photovoltaic system air-water heat pump - profitability single-family house KFW55EE

Is it still worth having two meters nowadays or should everything run through one?

That depends on many parameters: respective consumption, photovoltaics, basic fee, price per kWh, ...

With our consumption, it quickly amounts to over €1000 difference per year.

Oh, then you have a high consumption. Despite photovoltaics?

Do you even have a choice? In most grids, the supplier now requires two meters, regardless of whether it makes sense for you.

Who mandates that?

Who dictates that?

The network provider. For me, it is specifically Netze BW (EnBW), for you probably someone else ;)
That is stated in the connection conditions and the electrician who installs the meters must adhere to it

Well, with all due respect, we were also with EnBW in the first year and they only required that if we wanted a heat pump tariff, then with a blocking period and of course a second meter. Otherwise, I could have also gone with the regular one.

Something must be wrong there. 1000,- € difference equals 7700 kWh solely from the grid. With the current heat pump, that amounts to 30,000 kWh of heat. Before I start worrying about the meters, I would have my plumber come.

In general, it is now usually the case that it is not worthwhile to install a second meter in new buildings (because of the second basic fee). As the share of renewable energy increases, the price difference between heat pump electricity and regular electricity will also decrease, making it unprofitable for everyone else as well.

One must also consider that I have to install a different heating system if it is not allowed to run for four hours of the day. It then has to be designed about one-sixth stronger. If there is no more suitable option anyway, okay. But if I have to take the next larger model for that, I better forget about the second meter.

I researched the topic about a year ago and was somewhat frustrated because I had a document that clearly required a separate meter for heat pumps with usable power (greater than 2 or 3 kW). I just can't find it at the moment. I don't really want the second meter either.

So I never had one and my father had it removed without asking. So it seems to depend on the network provider...