Occupants' behavioural impact on energy consumption: 'Human-in-the-loop' comfort process control

Optimizing comfort for occupants and its related energy use is becoming more important. Presently, however, heating ventilation air-conditioning (HVAC) system installations often do not work in practice effectively and efficiently as the behaviour of the occupants is not included. The results are comfort complaints as well as unnecessary high-energy consumption. As the end-user influence becomes even more important within the energy process of sustainable buildings, it is necessary to integrate the occupants in the buildings' performance control loop. Laboratory experiments were performed to look for a correlation between infrared (IR) sensor temperature registrations and individual perceived thermal comfort in an individually conditioned workplace. It proved that it is in principle possible to use the third finger skin temperature as a control parameter for perceived thermal comfort. In another experiment in a real in-use office building, a wireless sensor network was applied to describe user behaviour on room and floor level. The results showed that it is possible to capture individual user behaviour and to use this to further optimize comfort in relation to energy consumption. Based on our experiments, we could determine the influence of occupants' behaviour on energy use and determine possible energy reduction by implementing the human-in-the-loop process control strategy.