Gas vs. Air-Water Heat Pump

It is important to remain flexible and be able to convert accordingly in a few decades (underfloor heating, low supply temperatures).

And we agree on that 100%

Then look at Switzerland, this is already being done in multi-family houses. These houses are not connected to the power grid at all. The houses are fully equipped (roof and exterior walls) with photovoltaics and in summer hydrogen is produced via electrolysis and nothing is fed into public grids. The rents for the residents are not much higher than usual.

Well, but if these houses were connected to the power grid, the whole hydrogen story would be totally uneconomical, right?
I find it a bit difficult now to pick such a special case and say: "See, they are doing it, so it makes sense."

Gas heating systems could also be operated ecologically (we already discussed this earlier in the thread).

And how? Is biogas currently fed into the gas grid in significant amounts anywhere?

Regards
Specki

And how? Is biogas currently being fed into the gas network in significant quantities anywhere?

This is not about biogas but about water electrolysis with subsequent methanation. This is how combustible gas is produced using electricity. Keyword Power to Gas. You can find information under Fraunhofer and "Herkulesprojekt".

This is not about biogas but about water electrolysis followed by methanation. This is how combustible gas is produced using electricity. Keyword Power to Gas. You can inform yourself under Fraunhofer and "Herkulesprojekt".

Power-to-Gas, like hydrogen, has the problem of being extremely inefficient. The efficiency is abysmal. I find it interesting as a storage technology as soon as regenerative electricity is produced so cheaply and is available in such abundance that the poor efficiency becomes irrelevant. For example, photovoltaic in the desert generates incredible yields, which are difficult to transport via the power grid and also have the disadvantage of the day/night cycle.

Yes, these are technologies that will come and are not yet inexpensive today. That is usually the course of development. Efficiency is an important and solvable issue.

Yes, sure. No, not enough.

and how large is your property? If it is sufficiently large, it might be fairly easy to install a loop collector trench with a heat pump. It is said to be very feasible there to achieve an annual performance factor of 4.5, which would mean getting 35% of the costs refunded by BAFA.

Until 01.01.2020, it wasn’t yet 35% of the eligible costs but a fixed euro amount, right? So now I get 35% back from the price of the heat pump itself, the craftswoman/man costs for the heating engineer/refrigeration technician, the brine agent, the pipes, and also the excavation work from BAFA? Which really would be a strong advantage for the loop collector brine heat pump because the acquisition costs are manageable anyway (compared to groundwater or deep drilling) and then you get another 35% back!?