Construction costs are currently skyrocketing

Oh, and one more thing:
Environmental protection involves more than just saving CO2.
Please also pay attention to a biodiverse garden (That means not a 100m2 towel garden with a neat lawn without flowers and a paved driveway so heavily covered that no blade of grass can be seen) – this is exactly the case in my neighborhood with almost all "new buildings".

So if I look at your picture, there is still much potential for improvement. A natural garden has nothing to do with new or old buildings.

1) The photovoltaic system is not sufficient to supply the in the critical months. If everyone had a heat pump now, we would have a power problem!
2) Your electricity is also partly generated from gas or coal power plants

The nice thing is that electricity can be generated in different ways. Depending on the current availability from sun, wind, or gas/coal. In addition, sector coupling can achieve really great efficiencies. A power plant with 35-40% efficiency runs heat pumps with an annual performance factor of 3.5-4 and also heats households connected via a heat network. This results in an overall efficiency of about 150-200%. A gas heating system can only burn gas at about 90%. With good planning and implementation (admittedly, that is a bit lacking), it would therefore be a gain even if the electricity is generated entirely from gas.

3) A gas heating system can also be used in the future with synthetically produced substances such as hydrogen or methane or whatever – hopefully economically in the future

Let's be realistic. First, hydrogen or hydrogen compounds are needed in heavy industry and aviation. Shipping as well, unless sailing ships make a comeback. Then possibly trucks. And only then private gas heating systems. And we haven't even talked about economic viability yet. The chain electricity -> hydrogen -> combustion results in about 50-60%. 60-70% for electrolysis, 90% for combustion, plus 15-25% transport losses. Electricity to heat via heat pump already has a COP=3 in winter today (typical value for A-7/W35), so 300%, transport losses for electricity in Germany are 5-6%. Electrolysis might improve a bit, but it certainly won't even remotely make up the factor of 6. Apart from miracle technologies, only imports from countries with really cheap electricity will help here. Is Desertec still alive anyway?

Why is that? Homo sapiens is naturally a carnivore.

I don’t get involved in any green fantasies. Nothing is questioned there.

I find you an impressive example of how demonstrably false things can repeatedly be stated with absolute conviction and how nothing is learned from the pointed-out mistakes – not even by the tenth account.

Homo sapiens is naturally not a carnivore but an omnivore. Both the jaw, teeth, and digestion are designed accordingly.
When humans were still hunters and gatherers, meat was rare and difficult to obtain. After a successful hunt, they “feasted,” consuming kilos per day. Regular food was purely plant-based; animal protein came mainly from insects. People ate what was available because they had to.

Today one can choose. There is no longer any necessity to consume animal products. It is a matter of willingness. Because it tastes good. Because one is used to it. But it is also possible without. For humans, no problem at all.

I still eat meat, fish, and animal products. Less often than before. Because I often do not find the conditions of husbandry and slaughter acceptable. Also, the sheer quantity makes me think: currently humanity slaughters about 88 billion farm animals per year, most of them chickens. Mostly without necessity, but because they want to and can.
The industrial killing of almost 90 billion living beings unnecessarily still horrifies me, even though I myself do not live meat-free.

Why is that? Homo Sapiens is naturally a carnivore.

He is an omnivore. Basically a flexitarian.

Nothing is questioned at all.

That’s typical of you, yes.

Oh, and what does all this have to do with construction costs!? :p

(...)
I still eat meat, fish, and animal products. Less often than before. Because I often don’t like the conditions of farming and slaughtering. Also, the sheer amount makes me thoughtful: Currently humanity slaughters about 88 billion farm animals per year, most of them chickens. For the most part without necessity, but because they want to and can.
Killing almost 90 billion living beings industrially without necessity still freaks me out even though I myself do not live meat-free.

Yes, terrible. One can hardly imagine how many trillions of krill a blue whale devours in its lifetime. That thing is the absolute mass murderer, good that we will soon have exterminated it.
However, it is also true that the 88 billion animals wouldn’t have lived at all, neither happily on the pasture nor unhappily in the barn, if the farmer hadn’t had the plan from the start to slaughter the animal and sell the meat.

What puts the icing on the cake of the post: I find it totally awful, but I eat meat and fish... then just stop if it's so easy? Sorry, but what kind of strange attitude is that? Do you cry when you eat your rump steak? How should one imagine that? :D

I hope no one ever finds out that bananas, tomatoes or soybeans also have feelings. Then the better people will have to starve.

By the way, we cause even far more suffering industrially in the world. Believe it or not, animals also have to die for the leather equipment of the new car, and for rare earths, which are also found in heat pumps, land areas the size of Bavaria are plowed up in the producing countries. After that, absolutely nothing lives there anymore ;) Not a single raw material that we process industrially in Germany, be it ores, fossil fuels, coffee, or cocoa, is produced in an environmentally friendly way in the producing countries. Child labor, massive environmental damage, pipeline leaks, desertification of landscapes...
But the main thing is to forgo pasture-raised beef...

Yes, terrible. You can hardly imagine how many quadrillions of krill a blue whale devours in its lifetime. It is the total mass murderer, this creature, good that we will soon have exterminated it.
However, it is also true that the 88 billion animals would not have lived at all, neither happily on the pasture nor unhappily in the barn, if the farmer had not had the plan from the outset to slaughter the animal and sell the meat.

What really puts the icing on the cake for the post: I find it totally awful, but I eat meat and fish... then just stop doing it if it's so easily possible? Sorry, but what kind of strange attitude is that? Do you cry when you eat your rump steak? How is that supposed to look like? :D

I hope no one ever finds out that bananas, tomatoes or soybeans also have feelings. Then the do-gooders will starve.

By the way, we cause far more suffering industrially worldwide. Believe it or not, animals also have to die for the leather interior of the new car, and for rare earths, as found in heat pumps, they plow up areas as large as Bavaria in the producing countries. After that, absolutely nothing lives there anymore ;) Not a single raw material that we process industrially in Germany, whether ores, fossil fuels, coffee, cocoa, is produced environmentally friendly in the producing countries. Child labor, massive environmental damage, leaks in pipelines, devastation of landscapes...
But the main thing is to give up pasture-raised beef...

Maybe read my post again. This time, for a change, with understanding.

1) You accuse me of things I did not write. Not even between the lines.

2) The suffering in one place never justifies that in another.

3) The blue whale has no choice either. It is the analogue to the hunter-gatherer. It does not breed the krill either.

4) The argument "life as a consequence of husbandry" is logically correct, of course. But, first, little reproduction happens voluntarily here, and second, the same argument, fully developed, could also be used for human children "in a one-sided dependency relationship." That is exactly what was done in America for a long time.

5) About crying while eating. I have raised and slaughtered myself (poultry). If I had not been able to do it, I would probably live vegetarian today. But I was able to.

District heating networks are certainly a good idea in densely built-up areas and will probably be implemented there first (apart from newly developed neighborhoods that are planned with this from the outset). In existing single-family home settlements, I would not initially count on them coming.

District heating networks can only be economically and ecologically viable where heat can be provided sensibly from renewable energies and, on the other hand, the heat line density (kWh / m of route per year) is high (2000+). This will very rarely or never be the case in single-family home areas. In more rural regions, there may be areas for e.g. photovoltaics/solar thermal energy/large heat pumps, but the network costs are correspondingly high.
On the other hand, district heating networks in metropolitan areas struggle with the problem of renewable heat provision. Example Hamburg: There are certainly approaches there, but I am curious how the three coal power plants Moorburg, Tiefstack, and Wedel, which primarily supply heat to Hamburg's district heating network, are supposed to be converted to renewable energies. Hanging heat pumps in the Elbe? Wind to heat? Deep geothermal energy? I am curious.

In short: Don't get your hopes up too much for the expansion of existing networks: The greatest challenge is the conversion to renewable energies in this sector.

3) Can a also be used in the future with synthetically produced substances such as hydrogen or methane or whatever – hopefully economically in the future

All reputable studies I know do not assume that (green) hydrogen can be produced in such quantities that it would be sensible to burn it nationwide in heating systems.

Why is that? Homo sapiens is naturally a carnivore.

Actually, humans are not even omnivores. Their digestive tract differs significantly from other omnivores. It is simply too short and not acidic enough. We can only digest meat well if it has been cooked or otherwise the proteins have been pre-digested.
Aside from that: Eating meat is like driving a Porsche. No one needs it, only a few people in the world can do it regularly, and it is disadvantageous for the rest of the planet. Those who do so do it not because it is necessary, but solely for pleasure. The same applies to all other animal products and foods in our industrial society: And YES, on a lonely island, if there is nothing else, I would also drive a Porsche, because then you simply have to.