Geothermal heat pump single-family house 200m² underfloor heating kfw55 - setting/optimization

At least, I am not aware of any possibility to connect the same photovoltaic system to 2 power lines for self-consumption.

It's called cascade measurement. It's not a problem.

It's called cascade measurement. No problem.

and does it also work if a bidirectional meter for the feed-in tariff is connected on one line?

and does that also work if a 2-way meter for the feed-in tariff is connected on one line?

That always works. Depending on the grid operator, however, sometimes with expensive technical effort.

question: I have only a temperature difference of about 3 degrees from inlet to outlet at the heat source. I read somewhere that it can actually be 7 degrees.

Where? In the "orange section" 2-3 K for the brine and 6-7 K for the heating circuit are "preached".

However, it is usually not worthwhile for low power consumption due to the costs.

It usually wouldn't be worth it with low electricity demand because of the costs.

well, for me both meters are simply connected directly to the grid. do i even have a right to demand that the grid operator "builds" me such a cascade metering? and if so, it certainly won't be cheap?! so currently i rather see it as a theoretical possibility. since the fact remains that the second meter hardly pays off even without photovoltaics (if at all) and with photovoltaics it rather becomes more difficult and expensive, i think the generalized recommendation is: with photovoltaics no 2 meters and without photovoltaics just calculate and see if it saves a few euros and compensates for the comfort loss due to the utility lockout. could that be generally acceptable?