How the timing of practices and appliance use contributes to evening peak electricity demand: Evidence from Danish time-use and energy use data

Temporal patterns in energy demand are becoming increasingly central to managing supply and demand in energy systems based on renewables. While past research has used either time-use surveys or high-resolution electricity use data to examine associations between energy peaks and everyday practices, these sources are rarely combined. This paper combines time-use survey data, including practices and appliances, with hourly electricity use data to investigate the association between the timing of everyday practices and energy demand in Danish households. Although the datasets were collected in different years, their combination offers new insights into the temporal alignment between domestic practices and peak electricity consumption. Focusing on the 5 to 8 pm evening peak period, the study examines four key practices (relaxation, cooking, housework, and caring) and nine common appliances, including the TV, coffee machine, and dishwasher. The findings challenge conventional assumptions that associate evening electricity peaks primarily with dinner preparation. While cooking is the most frequently performed activity during peak hours (60%), its direct contribution to peak consumption appears limited. Instead, practices such as housework, often involving energy-intensive appliances, emerge as more significant contributors. This reframing directs analytical attention away from isolated appliance usage toward the temporal coordination of multiple, overlapping practices. By directly linking the timing of activities with observed electricity demand, the study shows that evening peak loads arise from the temporal coordination of overlapping practices rather than isolated appliances. The analysis reveals that housework, often involving several energy-intensive appliances, contributes more to peak demand than cooking, despite cooking being the most common activity during this period. This highlights the importance of understanding appliances as mediators within bundles of practice.