Modelling household electricity load profiles based on Danish time-use survey data

The relationship among occupants’ presence, activities and appliance use is essential for households’ energy use. In the present work, we aimed to link occupants’ energy-related activities to electricity demand, in order to obtain a representative daily electricity load profile for Danish households using Danish time-use survey (DTUS) data.

The approach was to combine appliance ownership and power ratings with occupant activities from the DTUS. Two modelling approaches were implemented: in the first approach, the occupant activities profiles from the DTUS were used directly to determine activities at 10-minute intervals. In the second approach, the probabilities of starting time and duration of the occupant activities were used to determine activities.

In both approaches, appliance use was assigned to the energy-related activities. The set of appliances used in each activity was determined from a national database of appliance ownership, and the appliances’ power was calibrated using information from apartments in Copenhagen, Denmark. The modelled daily electricity load profile was compared with three measured datasets of varying sizes and from different parts of Denmark.

Both approaches captured important qualitative characteristics of the measured load profiles. However, the first approach used a more simple method and resulted in smaller errors than the second approach.