Heating type, insulation, KfW, photovoltaics - are components meaningful?

Two concepts emerge: Air-water heat pump and photovoltaic system is number one. Here I advise you to take it exactly as he offers it to you. Air-water heat pumps are not easy to adjust, so please take the model that the one who will also do the service knows best. The photovoltaic system is sensible, because my son-in-law has a Junkers air-water heat pump without photovoltaics, and the whole setup needs quite a bit of electricity: 2000 euros per year compared to 800 euros for my wife and me with a gas heating system. Thus, it seems worthwhile to generate the electricity yourself for this thing - but we also had a winter here in 2017-2018 where his air-water heat pump ran practically entirely on electricity, as it was minus 10 and colder at night. The other sensible concept is the good old gas boiler with condensing technology. Its advantages: very robust, easy to operate and maintain, space-saving, mature, economical. The disadvantage is the Energy Saving Ordinance: you have to have a renewable component with it. Please not photovoltaics, but solar for hot water. After all, the modules provide us with enough hot water from Easter to October that we can completely switch off the heating. The system is cheaper to purchase than the pump concept, and in consumption costs in my opinion not more expensive at the moment. It depends on the gas price. However, the gas connection has to be paid for, which is omitted with the pump. Karsten

Two concepts are emerging: Air-to-water heat pump and photovoltaic system is number one. Here I advise you to take it exactly as he offers it to you. Air-to-water heat pumps are not quite easy to adjust, so please take the model that the person who will also provide the service knows best. The photovoltaic system is sensible in addition, because my son-in-law has a Junkers air-to-water heat pump without photovoltaic, and all that fuss needs quite a lot of electricity: 2000,- euros per year compared to 800,- for my wife and me with gas heating

I almost agree. But with heat pumps, you shouldn’t just take the "standard"; unfortunately, you have to watch the provider closely, otherwise the costs can quickly be higher than with gas. In case of doubt, I would stick with gas, as mistakes are not so serious there.

Photovoltaics pay for themselves financially, independent of the heating system. During the heating season, there is no significant yield. Solar thermal hardly ever pays for itself, but it is often seen because it is the cheapest way to meet the requirements together with gas.

Hello everyone,

first of all, thank you very much for the many comments, opinions, and food for thought. Now I am finally taking the time to respond.

We told the developer that he can calculate the air-water heat pump with photovoltaics for his invoices. We are leaving the model open for now. We want to look at it at the next house building fair, with the heating installer, and if possible, see and especially listen to the model during operation. At the moment, we see this as the biggest obstacle for us. To paint the devil on the wall: the outdoor unit hums so loudly in the front yard that you can't sleep at night and eventually it just becomes annoying.

We are less concerned about the amortization. We are both young and the purchase prices of the components are comparatively affordable, even with installation.

In advance, we wish you a Happy New Year 2019 and all the best for the New Year.

To paint the devil on the wall: the outdoor unit hums in the front yard so loudly that you can't sleep at night and it just becomes annoying at some point.

I only know those damn things from the passerby's perspective - the homeowners put them in what they consider a good corner - and the buzzing bothers more than (less often) when they hum.

We are both young

Thanks, finally someone says that :)