ABSTRACT
The values for hot water consumption given in the literature have been found to be too high in practice: their use often leads to over-dimensioning in the planning of solar energy systems. The consumption values are frequently old, and have been calculated with the objective of providing security of supplies. Determination of the required data for the consumption profile should, if possible, be carried out by longterm measurements of the hot water consumption. If this is not possible, or is too time-consuming, then the following method can be used for acquiring the consumption data and using them for calculations in simulation programs.
