Which BHK block heating power plant - costs?

Look at it this way: you initially save a five-figure amount for the heating system (boiler, gas connection, exhaust pipe) plus roughly 200 euros per year for maintenance and the chimney sweep.

And you might save about 2 m2 that you would need for the boiler plus storage. That’s another approximate 4000 euros that you otherwise would unnecessarily tie up. Let’s say 15k initially plus 200 per year.

AFAIR you are bound to the operator for 10 years, after which the system belongs to the homeowners’ association or how was it? Let’s say the system is then depreciated.

Then you have saved yourself 1700 euros per year over 10 years (15k divided by 10 years plus 200 maintenance per year) for installation and operation. Opposed to that are only the elevated operating costs...

The prices for heat from a [Blockheizkraftwerk] are not exaggerated, rather affordable when compared to a district heating network. In the heating network, of course, you have a large investment share in network construction, which should be significantly lower in such a project.

The factor that may be decisive for the provider: with a [Blockheizkraftwerk] you will achieve a primary energy factor of 0.3-0.5; if it is somewhat larger with a corresponding electricity ratio, possibly even 0.0. In addition, you thereby fulfill the share of renewables from the [Erneuerbare-Energien-Wärmegesetz]. Thus, the provider can achieve KFW 55 or better without much additional technology, or at least meet all legal requirements without solar thermal or similar.

Look at it this way: you initially save a five-figure amount for the heating system (boiler, gas connection, exhaust pipe) plus roughly 200 euros per year for maintenance and chimney sweep.

And you might save about 2 m2 that you would need for the boiler plus storage. That's another calculated 4000 euros that you wouldn't otherwise have to waste unnecessarily. Let's say 15k initially plus 200 per year.

AFAIR you are tied to the operator for 10 years, afterwards the system belongs to the WEG or how was that? Let's say the system is then written off.

Then, over 10 years, you save about 1700 euros per year (15k divided by 10 years plus 200 maintenance per year) for the installation and operation. On the other hand, there are only the inflated operating costs...

How about if the system then belonged to the community? Would the price for electricity and gas change then?

How about if the system then belonged to the community? Would the price for electricity and gas then change?

Well, first of all, a combined heat and power plant is usually depreciated over 15 years, possibly other periods are also feasible. I haven't read everything, but a transfer is not contractually regulated, is it? Then the operator would probably not hand over the system for free, which also wouldn't reflect the technical condition.

Would the prices change? Yes, in which direction remains to be seen. Without calculating it, gas procurement through the homeowners' association would probably be much more expensive than through an operator who has multiple systems in their portfolio or is directly active as a market participant. In return, of course, they want their margin.
But what should not be underestimated: the operation of the system must be carried out by a qualified person. This includes inspections and maintenance as well as troubleshooting. An external party will charge well for this. Added to that are reports to the BAFA (possibly omitted until the transfer, since no CHP funding), electricity tax and energy tax refunds to the main customs office, reports and billing checks with the grid operator, and various quantity reports to the state statistical office and others. Additionally, there is internal billing and possibly the development and complex management of tenant electricity models.
Presumably, you would end up with around a 20-cent price per kWh for electricity. So a saving, but electricity still costs quite a bit.
After 10 years, the system will no longer be eligible for CHP funding (possibly not entirely with the not yet decided KWKG2020), so a significant positive price component will be lost. In addition, the combined heat and power plant will likely require a major overhaul, which for such a small system certainly represents 50-70% of the investment costs.

Combined heat and power plant is a very good infrastructure. If the thing breaks down, a new one comes in contracting. The solution is environmentally friendly and inexpensive. Your wish for a house really should not fail because of that. I would have connected my house to a combined heat and power plant owned by a neighborhood. We get our drinking water from a communal source. You really don't have to own everything yourself.

Well, that's the question. It may actually be good that it is environmentally friendly, but when I do my simple calculation with the basic data I have until the end of its life and still have to pay a higher 5-figure amount compared to a gas boiler, instead of just buying a house with a gas boiler right away, it does make me think. Unfortunately, as an IT person, I don’t know enough about whether it might be better to spend a bit more on the house and then probably save on electricity and gas in the long run.