The Incidence of Lighting System on Thermal Comfort Sensation: Experimental Evaluation

Considering the current climatic and energy crisis, one of the simplest energy-saving practices most easily implemented during this winter is the reduction of operation hours of HVAC system and the reduction of set-point value of the room temperature. From an energy point of view the benefits are undoubted, but what does the occupants feel in terms of thermo-hygrometric comfort? Can other factors, such as lighting color or control affect it? In the literature discrepancies were found between the classic comfort assessment models (such as the Fanger static model) and the occupant’s sensations. This could, in fact, depend on other factors that influence the psychological and perceptive sphere of people. The present study aims to investigate in an experimental way these aspects that have not very been deep in the literature. The analysis is performed in a full-scale living-lab conceived as a nearly zero energy building, placed in Benevento, Southern Italy. It will be shown that the building occupant judges the environment warmer than the one described by a static thermal comfort model. If there are warm lights it is preferable to be controlled by the user while the cold lights are preferable to be controlled automatically.