Evaluation of personalized environmental control systems to improve local thermal comfort during cooling season in Korea

Abstract

Heating, Ventilating and Air Conditioning (HVAC) systems in commercial buildings have often failed to capture and respond to the varying thermal requirements of occupants. Previous studies have verified that the use of Personal Environmental Control System (PECS) systems offer alternative options for HVAC systems without an expensive investment in existing buildings. The PECS in office spaces can respond to the individual cooling needs of occupants and have potential to improve different occupants’ thermal comfort. However, there is still a lack of research on the effectiveness of the PECS application under different HVAC system operating conditions (i.e., cooling temperatures) and the identification of the characteristics on PECS user groups in buildings. Therefore, this study investigated the effect of cooling PECS devices on the thermal responses of the occupants at different indoor setpoint temperatures and compared the effectiveness of the different PECS devices. For this, four cooling PECS devices were selected for cooling specific body parts (i.e., neck, body core, upper body, thigh). The cooling PECS devices were assessed using different thermal metrics for 14 participants in a private office in a university with 24^°C of the university setpoint temperature and 28^°C of the recommended setpoint temperature for national energy conservation. The results showed that using cooling PECS in an office space during summer could mitigate local thermal discomfort and lower the vertical and horizontal indoor temperature asymmetry. Among the various PECS devices, the desk fan was identified as the most effective device based on multiple thermal comfort metrics. The findings of this study provide a reference for cooling PECS applications with HVAC systems and have immense potential for solving thermal distribution problems in commercial buildings.