ᐅ Request for Explanation of the Energy Performance Certificate for a New KfW 70 Multi-Family Residential Building

Hello.
I want to buy a newly built apartment in a multi-family house (5 units).
The new building was completed in summer 2016.
Since this building was constructed according to KfW 70 standards and there are no reference values yet regarding energy consumption, I received the energy performance certificate.
The heating system is a pellet heating system supported by solar energy.

Regarding the energy performance certificate for residential buildings according to §§16 Energy Saving Ordinance:
- detached multi-family house
Usable floor area 900m2 (is this the area that should be used to calculate the pellet amount? Or the living area?)
Volume 2800m3
Envelope surface 1300m2

Final energy demand? 55 kWh
Primary energy demand 17 kWh
Solar energy 19%
Biomass 81%
Actual annual primary energy demand 17 kWh
Energy Saving Ordinance new build 52 kWh (-15%, -30%, -50%)

Question:
The building is therefore operated with a pellet heating system and a solar collector system on the roof (for heating support and hot water via a buffer tank).
The apartments have underfloor heating and window ventilation with bathroom ventilation.
The current owners told me that the pellet consumption is extremely high!
(December approx. 1.7 tons with no severe winter so far, Nov. 1.5 tons, Oct. 1 ton.)
More detailed information about pellet consumption has not yet been collected.
If I extrapolate the pellet consumption, I end up with an estimated pellet consumption of about 14 tons!

What would be the actual calculated pellet consumption for this building based on the energy performance certificate, approximately?
54 kWh/m2 with a usable building area of 900 m2 = 48,600 kWh.
About 5 kWh should correspond to approximately 1 kg of pellets. That would be 9,700 tons.
So much less than the actual consumption!

Or how can the approximate pellet consumption be calculated based on the data mentioned above?

Thank you very much

And here we go again ;-)
What exactly do you hope to achieve here? But it’s good to see that you slightly change your story with each attempt, at least it keeps things interesting.

Here we go again with the story. But you realize that you have a fundamental error in your calculation, don’t you?

How on earth do you come up with 14 tons?

The average consumption over three heating months was 1.4 tons. Over six heating months, that adds up to 8.4 tons, which is even less than you expected.

By the way, decide whether you have already bought the apartment or if you still plan to buy it.

Otherwise, everything has been said.

toxicmolotow schrieb:
Once again, the same story. But you realize yourself that you have a fundamental mistake in your reasoning, right?

How on earth do you come up with 14 tons?

The average consumption over three heating months was 1.4 tons. For six heating months, that adds up to 8.4 tons, which is even less than you expected.

By the way, decide whether you have already bought the apartment or are still planning to buy it.

Otherwise, everything has been said.

Hello.
Of course, I did not just multiply the December consumption by 12!
I calculated realistically. According to local residents, 1 ton was used in September!
In July and August, 500 kg. So in total about 14 tons.
The heating runs all year round, even though there are solar collectors on the roof for hot water... (That also puzzled me)...

That’s why I’m interested (I have not bought the apartment yet! A colleague of mine has bought one here!) in what the building’s energy performance certificate should estimate for consumption (of course, approximately). I understand that a new building (due to residual moisture) and incorrect ventilation/heating can affect the value.

But it should still be possible to establish an approximate consumption figure...

Hello,

rudiherbert schrieb:
...In total about 14 tons.

So there is a figure after all ;-)

rudiherbert schrieb:
..
That's why I would be interested to know.... what the building should consume according to the energy certificate (of course only approx.)

Such a thing does not exist. Try reading the fine print in the certificate.

rudiherbert schrieb:
...But it should be possible to set an approximate consumption value....

Reliable real consumption figures cannot be determined from energy certificate data. Other procedures and methods exist for this purpose.
The fact that this does not work was already shown by the experiment above with the 9.7 tons ;-)

Best regards.