Which heating system for the 200 sqm new building?

It is probably because most people do not really know what photovoltaics actually are and how and that it is cost-effective. In some new development areas, photovoltaics are mandatory for new buildings. This should be implemented everywhere in the spirit of the energy transition.

Amortization is usually between 10 and 15 years. So normally no one would invest there. However, the advantage is that the (low) return is relatively secure and calculable.

An amortization in 10-15 years corresponds to a return of 6.66 - 10%.
And that is _secure_ risk class 1, maximum 2. State guarantee thanks to the Renewable Energy Act.

Where do you put your money, in Zamunda?!

As a comparison: today, anyone buying or building an apartment in Munich expects a 40 (!) year ROI. That is 2.5%.
Including the risk (opportunity) of value changes, tenant turnover, tenant nomads and so on. Minus administration, maintenance, interest, etc.

Well, you probably get a better return on the stock market, the risk is minimally higher with a similar duration. So it would rather be my choice, because you can start with any amount and act more flexibly. And photovoltaic systems are scrap after 20 to 25 years. And then?

Besides, a lot is currently planned politically and the electricity price will tend to decrease due to CO2 redistribution.

That will ultimately finish photovoltaic systems off, since the return will then be gone.

Conclusion: Photovoltaic mainly makes businesses happy, because they really have high returns.

Well, you probably get a better return on the stock market, risk is minimally higher with a similar duration.

That is so ridiculously wrong that it hardly deserves any consideration.

Neither is the average (worldwide) return on the stock market (historically, who knows the future) equivalent, nor does the risk class correlate.

Sit down, six.

And photovoltaics are junk after 20 to 25 years. And then?

Nobody knows. From today's perspective: throw them away. They have generated dream returns for 20 years.

Besides, politically a lot is currently planned and tendentially the electricity price will probably decrease due to CO2 redistribution.

Protection of vested rights. Promises cannot be revoked. Constitution and such.

The profitability of a photovoltaic system is completely independent of the electricity price development. I have already told hampshire that.
You buy a system today at price X and know very precisely what it will generate in the next 20 years, thanks to law. This is not a gamble. (Risk class 1)
For the residual risk, there are insurances that usually cost the average person nothing, because they are included as long as you ask for them.

That will finally finish off photovoltaics, since the return will then be gone.

It will be exactly the opposite. The gas bill goes from €50 to €200 a month, everyone else will laugh.
That would be at least the rational strategy. The black one will be to prevent that for as long as possible. Simply no alternative.
That makes your knees shake.

Seriously , how do you come up with so much nonsense?
The gas going from 50 to 200 is a bit exaggerated, but otherwise you can only agree with guckguck.

Isn't it also possible to finance a photovoltaic system cheaply through the KfW? Then it would be a return with other people's money.