The daily consumption is related to the number of planned full occupancy persons (fop) and not to the number of persons actually living in the building in the individual weeks. We selected this reference figure, since this is generally the only figure the planners receive from the operator for the dimensioning of the solar installation. In the case of a planned new building, there are no other figures. This figure demonstrates clearly how important it is to carry out measurements in the case of existing buildings, since the great spread in experience hardly permits a matched dimensioning in individual cases.