Computational Consideration of Various Energy Concepts

The type of heating concept, renewable shares, etc. is a calculation task, clear so far. We would also prefer to work with a ground source heat pump and hot water support. However, the whole thing makes no sense if it only pays off in 30 years and the heating system then has to be replaced almost again.

My question is now: What do I need in order to carry out a reasonable energetic assessment? What key data do I need from my planned single-family house? Are there example calculators on the internet with which one can roughly calculate such a thing? Or can only a (expensive) energy consultant do something like this?

Hello Kirsel,

in my opinion, the most important key date is the development of energy prices. So if you want to carry out a reasonable energy assessment (as I read between the lines, reasonable means the cheapest), then you should look for someone who knows about the development of energy prices over the next 30 years. Everyone else only creates models that have a more or less small chance of becoming reality!

Sometimes you can save more money through an investment that seems expensive at first glance (energy consultant) than through the cheaper option (internet self-research).

Regarding heating: There is no general statement, you have to take many individual, partly individual, partly structural, and partly financial circumstances into account.

Good luck

K.Brodbeck

Seriously? Find someone who knows the price development for the next 30 years? I think that will be like searching for the holy grail, or a pact with the devil. my very humble layman's opinion: €uro look away You should simply aim to build a house that requires little energy. And then the type of heating doesn't matter. We heat a Kfw55 house with a gas boiler. That currently costs us less than €50 per month. (pure gas consumption). In my opinion, it’s not worth operating an expensive geothermal heating system. And whether you want to have a fan standing in front of the house is up to everyone to decide. However, I must say: we built a prefabricated house and trusted the energy concept of the provider. It was a small risk, but since we didn’t want underfloor heating anyway, the gas heating was a given.

Seriously? Finding someone who knows the price development of the next 30 years? I think that will be the search for the holy grail, or a pact with the devil.

Ah, he has recognized it!

....my very modest amateur opinion: €uro look away

Why, it is completely legitimate that you express your opinion here! So far, I have not encountered any clairvoyant of future energy price developments depending on the energy source! One thing, however, is certain: they will rise more or less strongly. Electricity is the most elegant and flexible energy carrier. It is not entirely nonsensical but burdened with the highest taxes, levies, and fees. The security strategy is certainly demand reduction from the outset, meaning KFW 55, 40, or PH. Whether I would build a PH in the Sahara, however, is rather unlikely; at a location of my building on the Zugspitze, on the other hand, very likely! Higher demands do not come free of charge; gifts are not given out at all. Therefore, a sense of proportion is certainly more appropriate than a general broadside from those who think they have found the philosopher's stone! Almost everything can be sold! As is well known, the truth lies somewhere in the middle between the extremes. It can be found relatively easily with some effort; anonymous advisory forum posts are usually unsuitable for this!
Best regards

One should simply look to build a house that requires little energy. And then the heating method doesn't matter. We heat a KFW55 house with a gas boiler. Currently, that costs us less than 50 € per month. (pure gas consumption). In my opinion, it's not worth operating an expensive geothermal heat pump. And whether you want a fan standing in front of the house, everyone has to decide for themselves.

We build like this too, but we will even end up below Kfw40. A well-insulated building envelope is paid for only once and immediately brings savings effects that are always there. No maintenance and expensive renewals are required, as is the case with a heat pump, etc.

With windows, the price is driven much more by the material (e.g., wood-aluminum vs. plastic) than by the thermal insulation properties (double vs. triple glazing).
The same goes for the masonry: expensive Poroton and cheaper Twinstone or Gisoton have the same thermal insulation values, but Poroton is traditionally built with the well-known red bricks. You have to weigh what is more important to you.

You can also build relatively cheaply with good insulation.