ICT intelligent support solutions toward the reduction of heating demand in cold and mild European climate conditions

Adopting intelligent solutions in residential buildings for reducing the HVAC energy demand, especially during the operational stages, is becoming more popular. Information and Communication Technology (ICT) devices are often the backbone of such intelligent solutions, since they can enable an easy and intuitive bidirectional communication between energy systems and users and, at the same time, are able to suggest energy saving procedures. These energy saving procedures are mainly suggested when energy hungry behaviors are registered. Particularly, authors of this paper have assumed setting indoor set point temperatures, adjusting ventilation airflow rates and opening windows as energy hungry behaviors to tackle by means of ICT-driven intelligent solutions. Two different localities, namely Helsinki and Milan, have been considered as representative of cold and mild European climate conditions. Results report that adopting ICT-driven intelligent solutions for setting heating setback and indoor set point temperatures and for controlling the mechanical ventilation according to actual people’s presence and CO₂ levels ensures consistent reductions of energy demand, especially in Helsinki, where mechanical ventilation is adopted. Moreover, if mechanical ventilation does not work properly or is missing, benefits in reducing energy demand can be even achieved by adopting ICT-driven intelligent solutions for advising building users when windows should be opened or closed according to sensed CO₂ levels. This is relevant especially in Milan. The adoption of intelligent HVAC–window controls, which enable to turn off the HVAC when windows are opened, does not ensure a significant effect in Helsinki. Instead, this solution is promising in Milan, especially when heating systems with low thermal masses are installed.