Estimate electricity consumption with heat pump

I have read this three times now and have to admit that it confuses me more than it helps. That means that the same building envelope is classified very differently in terms of final energy demand, depending on whether I generate the heat by gas (~1:1) or heat pump (1:3.6)? The factors for primary energy demand correct this a bit, but in the example gas would still be 1.1 and the heat pump 0.5 kWh primary energy per kWh heat?

The certificate does not evaluate the envelope, but the house as a whole including the technology.

The final energy demand indicates how many kWh of the used energy carrier are "brought into" the house. I can use heating oil, electricity, natural gas, wood pellets, etc. there. The primary energy factor then takes into account the impacts of the energy carrier on the environment or renewable shares – that is why the factor can also be less than 1. Wood, for example, is rated as 100% renewable, but still 20% of the energy content is accounted for as additional effort for transport and shredding. It is correct that some shifts take place here through heat pumps, while for gas and oil the final and primary energy demand differ only slightly.

For approvals, funding, etc., the primary energy demand is always considered because it takes into account both the envelope, the technology, and the climate impacts of the used energy carrier. This is also understandable because a low overall value should be achieved, and e.g. a particularly good insulation standard may then be allowed to be heated somewhat less efficiently, e.g. with direct electric heating in passive house standard in some cases.

For the operating cost estimate for buyers, the final energy demand is relevant again. The certificate also always contains the usable floor area of the building to which the value refers, so that the determination of the absolute value is possible.

The certificate does not assess the shell, but the house as a whole including technology.

The question is, who understands the difference if they are not an energy consultant. This thread shows that even interested laypeople do not understand it. 99% probably calculate final energy demand = heat demand. The energy certificate lacks the unadulterated indication of pure heat demand, because different energy carriers do not have the same cost. A final energy demand of 50 kWh/sqm for gas is a completely different matter than the same final energy demand for a heat pump. However, the energy certificate suggests that both houses are comparable.

The energy certificate lacks the undiluted indication of the pure heat demand, because different energy sources are not equally expensive. A final energy demand of 50 kWh/sqm with gas is a completely different matter than the same final energy demand with a heat pump. However, the energy certificate suggests that both houses are comparable.

The energy source used for the calculation is always listed (just not shown in the excerpt of the photo from the questioner).

The certificate clearly states (example values): Final energy demand: 10 kWh/m²a Used energy source: electricity Usable floor area of the building: 200 m²

How much heat is generated from the respective energy source is irrelevant for the user who wants to know how expensive the operation is.

The second value is then relevant for the official assessment and not so important for the user.

The individual values (heating demand, hot water heat demand, useful heat demand, solar heat gains, possibly accounting for photovoltaic system, etc.) can be output separately by the calculation software but are not part of the energy certificate (because THAT would confuse 99% of readers). Upon request, however, every reputable energy consultant will provide them as a short report (can be created with one click).

Therefore, both values make sense. The determination of the values is not so easy to understand, but in the end, both values make buildings comparable to each other in terms of energy efficiency and expected operating costs.

That is all correct, once you know that final energy has little to do with the heat demand. I just clicked around a bit on the internet. Partly it is stated incorrectly (e.g. "Endenergiekennwert: How much thermal energy do you need to supply the building with heating heat and hot water?"). The rest is so imprecise regarding the exact meaning of final energy that you have to know the meaning beforehand and otherwise assume as a layperson that it refers to the heat demand. I have the feeling that, for example, the consumer advice centers themselves have not understood 100% what the difference is.

Very interesting but somehow I still haven't fully understood it at least since I dug out my old energy demand certificate from 2003/2004. According to it, I would have an annual heating energy demand of 15560 kWh/a.

[ATTACH alt="stromverbrauch-mit-waermepumpe-schaetzen-642072-1.jpg"]82027[/ATTACH] Here a ground-source heat pump was assumed. A air-source heat pump was installed. But why is the annual primary energy demand so high at 17364.48 kWh/a

According to this, I would have an annual heating energy demand of 15,560 kWh/a. Here a ground source heat pump was assumed. A air source heat pump was installed. But why is the annual primary energy demand with 17,364.48 kWh/a so high

The heating energy demand is shown as 15.5 MWh The final energy demand (electricity) is 4.95 MWh + electricity for the circulation pump (auxiliary energy) The primary energy demand is determined, as previously mentioned, by the primary energy factor from the respective energy carrier. For you, from kWh electricity * fP for electricity from 2004. The fP values are regularly reassessed by the Federal Environment Agency and are also politically influenced (lower fP for heat pump electricity, higher fP when accounting for electricity generated in combined heat and power plants). In 2004, the fP for electricity was simply significantly higher than today, apparently about 3.5. Today the fP for grid electricity according to the Building Energy Act is 1.8. In fact, in 2022 it was just over 1.4. As mentioned, politically influenced.