Combined heat and power plant with fuel cell - THE alternative?

Hello,

I am planning to build a house (living space 80m2, bungalow) and would like to produce the electricity myself.
After various discussions with architects and experts, I came to the conclusion that solar systems are not for me.
Specifically, the durability and maintenance were strong points of criticism.

After some research, I am interested in a combined heat and power plant.
With it, I could produce electricity and heat myself.
Weather-independent and, according to Stiftung Warentest, almost maintenance-free as there are hardly any moving parts.

I have the Viessmann Vitovalor 300-P in mind.

Has anyone had any experience with it? Does it pay off in the long run?

You don’t just burn gas for heat but also for electricity. The question is what the kWh of electricity ultimately costs, that is, whether it is worth it. The system itself costs about €20,000 on the market. In contrast, there is a considerable Kfw subsidy and a tax relief on gas consumption.

No.

Reason: Investment costs too high.
I thought that combined heat and power plants only exist for existing buildings - but I could be wrong.

The alternatives of heat pump + solar are also not free. After deducting subsidies etc., the combined heat and power plant is just under €10,000. Maintenance is €200 per year, I pay the same for (almost) any other maintenance.

On the other hand: electricity in all seasons and weather conditions for free, the combined heat and power plant covers the entire demand. Natural gas costs are around €500 and less.

How do you come to the conclusion that the investment costs are too high?

Electricity is not free, you have to burn gas for that! Since basically no heating is done for half a year, the combined heat and power plant then has to run almost exclusively for electricity production, how efficiently is 1kwh of gas then converted into 1kwh of electricity?

from unterwegs

Ok, to be honest, I didn't consider that. On the other hand, there is hardly any sun (Solar) in winter, and in winter there is also hardly any heat (Air heat pump).