Cold local heat with ground source heat pump

Not at all. It depends on the heat pump, the heating system design, and you. I simply assumed an annual performance factor of 4, which should definitely be achievable with geothermal energy. If the heating system is well designed, 4.5-5 are also possible.
The calculation means that you produce four kWh of heat from one kWh of electricity. If you even get five kWh from one kWh, the working price would correspond to an electricity price of 30 cents.

Paying for both, i.e. one kWh of electricity for operation plus the labor costs for four or even five kWh of heat, would be madness.

I'll show you the price regulation here as a photo... you can give your opinion on it...!! Thanks ☺️

Very low unit price, high one-time costs, fairly high fixed costs. Conclusion: In my opinion, average

The problem is that you commit to a monopolist for 10 or more years. There is no competition. Conditions are non-transparent and hardly directly comparable. Sometimes you pay for electricity, sometimes for hot water separately, sometimes low investment, sometimes you have to buy the heat pump yourself,...

Do you have more precise information about that? This colorful info page doesn’t reveal much. Who supplies the electricity for the heat pump? Since the price of 5.95 ct probably refers to the heat generated, the situation arises that the more effective the heat pump works, the more your provider earns from it. By the way, 500 euros per year is already what many pay for their heating consumption overall in well-insulated houses.

Here is the overview of the costs... if I understand point 2.2 correctly, the basic price of 487€ also includes the electricity for the heat pump, which is why they don’t want me to feed my own electricity from the photovoltaic system into it..!!! Is it legal for them to forbid me from using the electricity from my photovoltaic system for the heat pump?!

Is it legal that they forbid me to use the electricity from my photovoltaic system for the heat pump?!

Yep. Eat or die.

Not at all. It depends on the heat pump, the heating design, and you. I simply assumed an annual performance factor of 4, which should definitely be achievable with geothermal energy. If the heating system is well designed, 4.5-5 is possible.
This calculation means that you generate four kWh of heat from one kWh of electricity. If you even get five kWh from one kWh, the price per unit of work would correspond to an electricity price of 30 cents.

Paying for both, that is one kWh of electricity for operation and on top the labor costs for four or even five kWh of heat, would be madness.

but that’s how it is currently, or how should the contract be understood? Please post the costs again as a photo...
With the current contract, we pay a one-time fee of €17,400, then the base price of €500 (which includes the electricity for the heat pump, under point 2.2 it says ....the costs for operating the heat pump....) and then we also pay for the heat that the heat pump produces with the already purchased electricity... so that’s how it is according to the contract currently, right?
So I pay the electricity for operating the heat pump and for the heat produced with the already purchased electricity, or am I missing something?

No, you do not have a thinking error. You pay operating costs, i.e. electricity, maintenance + costs for heating. The operator takes care of maintenance etc., although the wording with the basic price confuses me since only operation, measurement, and billing are included there.