New gas heating system - How to design underfloor heating based on a heat pump?

I am a bit confused, the lifespan and reliability of a ground source heat pump can indeed be tracked. The technology is extremely old, it is only currently gaining popularity because the efficiency has been enormously increased. I have read a lot and sought advice. What gas and electricity prices will bring in the future is the bigger question in my opinion. Otherwise, the maintenance costs are, as far as I know, much lower and one could also calculate that a ground source heat pump pays off after about 12 - 15 years. However, I do not want to speak ill of gas, just to operate a stove with gas, I know enough people who only have gas in their houses. In general, I also had the budget issue, gas or ground source heat pump. I said that we are taking the ground source heat pump now instead of paying twice in the end. Gas definitely will not come into the house anymore (the connection will not be laid either), in the hope and expectation that the ground source heat pump (depending on electricity prices) will pay off as soon as possible...

Well, prices are rising, whether electricity, gas, or oil, I don’t think it will get cheaper with any medium.... and I also don’t believe that gas is getting much more expensive than electricity now.... But it’s always a look into the crystal ball, that much is clear. What can be calculated more easily is the savings I have to achieve for heat pump technology to be worthwhile... With an additional cost of 13,000 euros, I have to save 866 euros per year for amortization after 15 years... someone please convince me otherwise. Even if I generously calculate savings for connection and maintenance, I would have to save a good 60 euros per month in energy costs for a geothermal heat pump technology to pay off after 15 years.... For the gas heating, I have budgeted monthly costs of 80 euros for us.... in other words, a heat pump should cost me 20 euros per month in maintenance, then I would go for it ;) I am now getting an offer for an external air heat pump... let’s see where we end up price-wise but since there apparently is no funding anymore, the topic will probably be put aside for now.

Hello,

We are building according to KfW70, which we achieve even without solar through a controlled residential ventilation system (Helios), which is required in the development plan anyway.

With the Swiss, you have found a very good supplier for the controlled residential ventilation. Take a look at their other product offerings; "I" could almost wish to win the lottery, although a purchase has become cheaper nowadays. Heliobus has had a branch in Germany for about 2 or 3 years now; therefore, the customs fees no longer apply.

Our budget is 180k, which we have already slightly exceeded. All extras are already included. (130 sqm floor area, gable roof, rectangular shape)

But surely some extras are already included in the 180k EUR for the house?

Yes, as described, I think there are pros and cons to everything... if money were no object, I would go for a geothermal heat pump... but with the uncertainties about lifespan and reliability, I currently see no reason to pay the extra cost. Also because we have gas directly on the property and therefore the connection costs (which are also subsidized by the local energy provider) remain limited.

Either it's subsidized or district heating is mandatory; somehow the utility providers have to recoup their costs ;)

Rhenish greetings

Well, no one can guarantee how quickly the amortization runs. You can also be unlucky and a heat pump breaks down early... I do not claim that a geothermal heat pump is a jack-of-all-trades or anything like that, in my opinion gas is a solid option to create a clear calculation. You know in advance that maintenance costs, chimney sweep, etc. will be incurred. Everything else depends on personal preference, how warm you want it in the apartment. 19° is enough for me... But if I want 22 - 24°... then the calculation really starts! What personally bothered me about gas was that in the consultations the additional costs were always swept under the rug. On average you read about 300 EUR, sometimes more, sometimes less. The lifespan of a gas heating system is about 15 years according to what I have read. I believe that with my relatively low heat demand the geothermal heat pump already makes sense. I am also happy to be convinced otherwise ;-) Basically, my point was just the statement that there are uncertainties about the lifespan and reliability. The lifespan of any heating system can by bad luck only be a few months, but usually we are talking about 20 years or even more. For gas I have the information that on average it is 15 years. There are enough pros and cons for both, but in one point the gas heating system has the advantage: it is well calculable, despite additional costs!

When it comes to additional costs, please do not forget the loan. If it costs €5000 more, in the end it is certainly not just €5000 more. .....you pay the interest on the loan if the extra cost is not paid in cash and it becomes even more expensive.

I have been living in my 124sqm new building for a year now (KfW70 three people). Last mild winter I used about 800 cubic meters of gas. However, I have 2 solar collectors for hot water on the roof. I did turn off the heating from May to October (hot water only solar) but it does not pay off. For hot water, you need significantly! less than one cubic meter of gas per day. For the inspection, the heating people want €100-180 per year (cleaning and new seal).

Of course, the financing costs must also be taken into account. However, please do not forget to allocate the probe(s) of the brine heat pump over a lifetime of the house. When I calculate the solar collectors, which are often installed with gas to achieve Kfw70, it is even more questionable for me, as these never pay off.