Construction costs are currently skyrocketing

The topic of backup power/emergency power for a heat pump is interesting. It would be important to know whether a photovoltaic system with/without a battery can help and how the technical implementation is.

As long as you are not operating an off-grid system and your battery is not black start capable, photovoltaic + storage is of no use to you. I am only concerned with protecting the equipment. The UPS is not supposed to last through the night, but rather 5-15 minutes.

That doesn’t help you if you don’t have 50 kWp on the roof to charge a 15 kW battery in winter. Your heat pump will still drain the battery faster than you’d like.

See above. The UPS serves only as equipment protection. That is correct, photovoltaic + storage brings you practically nothing in gloomy winter months. A sunny January day is then an exception. For this, you actually need an emergency power generator - realistically speaking, that probably won’t happen, you will have other problems than watching TV anyway.

Our media are in large parts just as populist and deceitful as those of the Russians. 90% of Russians think their media are honest and therefore support the war. With us, it is exactly the other way around. But it is easy to settle into the majority and lies. I understand that.

You have no idea what it means for the media to be controlled by the government. I would recommend as a deterrent TVP in Poland. Currently, it is being discussed there (also by high government members) that Poland has received more sanctions from the EU, which is controlled by Germany, than Russia. The reason is the blockage of the Corona payments from the EU.

Regarding ramping up biogas, I put a big question mark behind that? What is it supposed to be fed with? It is ecologically and economically nonsense to put up even more when you consider the overall impact (corn, for example, needs an incredible amount of water and dries out quickly). A large geothermal basin is currently being built in Meldorf based on the Danish model ....so it's somehow progressing.

Our media are in large parts just as populist and deceitful as those of the Russians. 90% of Russians think their media are honest and therefore support the war. With us, it is exactly the other way around. But it is easy to settle into the majority and lies. I understand that.

Well...primarily, the Russians are in a foreign country and not the other way around. None of the sides deny that. In my understanding, that clearly makes one the aggressor. We are not in kindergarten where a "but he provoked me" argument is valid! In my opinion, one can always fall back on this very simple fundamental truth. edit: And yes, that also makes the USA largely the aggressor in parts of the Middle East. (As for missions like Mali by the Germans... that gets complicated)

Just asking here: Is the storage actually usable when the inverter is off? In other words, if the grid is not supplying power and the inverter is dead, can the storage even be drained?

Depends on the inverter, but without power, the inverter should then be kept alive by the battery.
It's called island mode or off-grid.

It depends on the inverter, but without power the inverter should then be kept alive by the battery.
This is called island operation or off-grid.

Thanks! However, to my knowledge, most systems do not run in "island operation," so in most cases the storage is not useful for that!?

We are not in kindergarten here where a "but he provoked me" is accepted!
In my opinion, one can always fall back on this very simple basic truth.

You said it, we are not in kindergarten! Therefore, complex matters should indeed be examined a little more deeply in order to better understand the connections between causes and effects. This applies generally and not only in this case.