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

I believe it wouldn’t have been worthwhile for us at that time and we received a different/better offer from our bank.

Better? Maybe with a longer fixed interest period. Cheaper? Definitely not, since the effective interest rate at the KfW is negative. A normal bank won’t do that. But aside from that, the heat pump is so oversized. I have my doubts about your heating planning. Sounds like it looks good on paper, but in the end it will be expensive.

Better? Maybe with a longer fixed interest rate. Cheaper? Definitely not, since the effective interest rate with the KfW is negative. A normal bank will not do that. But aside from that, the heat pump is way oversized. I have some doubts about your heating planning. Sounds like it looks good on paper but ends up being expensive.

Unfortunately, I can't answer that either. I only know that our neighbors have the same heating system and their house is a bit smaller. Apparently, this is common with some home construction companies.

Apparently, this is common practice with some home construction companies.

Yep. That way, as an installer, you don't have to think or plan. You save material (e.g., no closely laid heating circuits), but you get charged well for it. As the icing on the cake, the planning error is compensated by an oversized heating system. And again, you pay too much because the heat pump is estimated to be 3-4kW too large. With the heating costs, you end up paying a third time.

Works like a charm!

e.g. no closely spaced heating circuits),

I have the same concern.

@TE: do you have pictures of it? What kind of construction is that anyway? You basically bought the house finished with the land from the BT/GU?

Heat pump price is good, household charges are a disaster. We pay 28 cents plus 100 euros basic fee, with the bonus offset it is 17 cents per kWh.

Which bonus? What did I miss there?

The crucial factor in a modulating heat pump is the minimum output. It can certainly still be small enough at 8 kW.