Outdoor air-to-water heat pump is smoking and steaming

In the end, it's quite theoretical with the sun anyway. The solar thermal of the gas heating system practically brings nothing in winter, exactly when it would be useful. I read a few days ago that we had about 15 hours of sun in total during December. As a result, photovoltaics also contribute relatively little to operating the heat pump. You can calculate both options nicely or not. On the cost side, the gas boiler is certainly still at an advantage at the moment. However, the political will seems to be different. For an unrenovated old building, it certainly won't be fun in 10 years. An efficient new building has a completely different calculation because it simply loses less energy. But every calculation is void since it has to estimate a future gas price and electricity price.

Therefore, it is wise to consume as little energy as possible. Then the price can be relatively irrelevant. Anyone who usually refuels for €250 per month will already notice the CO2 price in 2021. This applies equally to the house.

The solar thermal system of the gas heating system practically brings nothing in winter, which is exactly when it would be useful.

Only new findings today here, heating water with solar energy is only sensible in winter. Not for the remaining 3/4 of the year?

Certainly, it is true that solar thermal ultimately yields less than photovoltaics. But it is also not as costly in procurement, etc. Not least because you don’t need to cover that much area.

Everything, really everything, must be calculated and not generalized. Every house is different, and depending on the conditions and possibilities of the builders, this or that setup can be the more economical option.

cool would be a property with a thermal spring...

In Scandinavia nothing unusual. :)

Only new findings today here, heating domestic hot water with solar energy only makes sense in winter. Not for the other 3/4 of the year?

A colleague said she can draw tea water directly from the tap in summer ;)
But aside from that, in summer you only need a very small part of the hot water for showering, in winter the demand for heating is significantly higher. But you surely know what I meant.