Vestaxx window heating - experiences?

So, if the heat pump would not consume any electricity at all and I have to pay about €2000 per year for electricity with an electric heater at 40ct/kWh, and the price advantage is €23,000 + €16,000 interest = €39,000, I could pay for electricity for 19.5 years until the heat pump caught up with me?? If it cost nothing in consumption?

and if the heat pump only consumes 900 kWh during that time with an annual performance factor of 5, x 40 cents, that is another €7,200 in 20 years, which would mean the heat pump only pays off after almost 23.5 years. But in those 3.5 years, I have also paid another €2,600 in interest for the additional €23,000 cost? So I break even only after 25 years?
Well, I am almost 60, a heavy smoker, and for the next construction, since I have no heirs, I should probably set up electric heaters before installing another heat pump.
Great.

So, I’m almost 60, heavy smoker, and since I have no heirs, I’d probably better set up electric fan heaters for the next build before I let another heat pump be installed.

True! Well observed. You can also just open the oven in the living area and run it at 30°C. In the bathroom, a hairdryer suffices. Finally a reasonable conclusion!

Or, we build a house that can also be operated sustainably and with low running costs by other people’s children. A house where each fluctuation in energy prices is mitigated by a factor of 4-5 via the annual performance factor. Where you buy security for cheap operation for the next 50 years (of course not with the first heater). Plus comfortably warm feet and a floor where kids can play without having to lay carpet or blankets everywhere. Where it’s simply cozy and in summer you can even cool using the cooling function of the heat pump.

If you want to argue about interest rates, here are two screenshots from a construction financing provider and a loan higher by 20k.

Cheap heating system:



Heat pump



As can be seen, we have roughly equal monthly costs when operating costs are factored in. I maintain, I would not recommend this system to anyone who isn’t at least building a passive house. Normal single-family home construction should be significantly more comfortable and safer in the long term with a heat pump and underfloor heating.

One more note on sustainability. It’s telling how you completely ignored that aspect, , and rather wrote another “Wall of Text” about what else one could buy. Which, of course, might also be due to individual life circumstances.

I'll throw in a semi off-topic comment that as of today, on average, heat pumps are operated far from optimally. Regulations(?), poorly trained heating technicians, ERR instead of proper hydraulic balancing, resulting in lower efficiency combined with higher wear.

Addressing this and unlocking potential seems to me at first glance somehow more important than now pitting electricity-based heating systems against each other.

So, you assume in your calculation that the heat pump with underfloor heating costs €23,000 more than the window heater?

You have to consider that probably calculated with 80 instead of 50-80 for underfloor heating.
And for the air-water heat pump, I strongly assume he used the "moon calculation" from the general contractor for the BAFA funding and then added another 30%.

I had to recalculate this in my head now:
so then I save about €16,000 on interest in 20 years?
or am I miscalculating here? I assumed 3.5% interest

The answer here is even simpler. Yes, you are miscalculating.
Interest would be €9,013, but can be completely ignored since the increase on electricity is also not taken into account.
If that is also around 3-4%/year, it balances out.

One has to consider that Here the answer is even simpler. Yes, you are miscalculating. Interest would be €9,013, but can be completely ignored, as the increase is also not considered on the electricity.

Correct, otherwise the window heating would have even less chances... 2010 - 2021 (Pre-Ukraine): 36% increase 2010 - 2022: 62% increase So if we calculate with an amortization of 20 years, we can also reasonably expect a doubling of electricity prices...