The time-use data is only available for one weekday and one weekend day per household, and therefore the model only generate average profiles for one day of each type, not depending on season

or day of the week. To enable further model development the time dependent variations in load measured in the 24 apartments are investigated below.

The energy use for hot water for different months, expressed as average daily demand per average household member, is found in Figure 3. The lowest hot water consumption is found during the summer months and the highest consumption during winter. The average daily energy use for hot water is 5.4 and 4.4 kWh/person for 2005 and 2006 respectively, with a variation of the maximum and minimum consumption of ±17-26 % around the average. The results correspond well to the monthly relative variations found in [9].

The half-year including summer is investigated more in detail in Figure 4, showing the weekly variations in hot water demand in April to October. A clear minimum is found in July and August, which is the usual vacation period in Sweden.