Is it possible to have different energy certificates for the same house?

Hello community,

I have been looking for a home for about 2 years now, and there is a semi-detached house, or rather two semi-detached halves, for sale here in the village. One half costs almost double what the other costs. I think the difference can be found in the energy certificate: one half consumes (allegedly) 160 KWH per m2, the other 480 (!) KWH per m2, and that with the same masonry, the same windows, and the same front door. The half that supposedly consumes less according to the energy certificate has a consumption certificate, the other has a demand certificate. Personally, I can’t imagine that a consumption of 480 KWH per m2 is realistic, or the occupant of the other half would have to be sitting at 14 degrees and with mold in winter. However, there was no mold visible anywhere, and it didn’t seem to me that the tenant living in that half is someone who feels comfortable at 14 degrees. How is this difference of over 300 KWH rationally explainable, or to put it another way, does the demand certificate, which to my knowledge is only calculated, actually tell you anything?

Many greetings

How is this difference of over 300 KWH rationally explainable or, to put it differently, does the energy demand certificate, which to my knowledge is only calculated, actually say anything at all? Best regards

- Demand is calculated somewhat reasonably based on the building fabric - Consumption you get in three minutes on the internet - Different areas may also be considered (e.g. with consumption you "accidentally" enter the floor area including the attic and unheated basement) - Consumption can also actually be a only half-heated house Etc. Consumption is (very often) rubbish.