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Green roofs' (GR) positive impact on indoor thermal conditions in hot areas may have possible negative impacts during hot and cold weather. Most previous studies have focused on GR's positive effects as a standalone strategy without mitigating these side effects of GR application. This study contributes to a more comprehensive understanding of the impact of GR and how to mitigate the negative aspects by integrating it with other passive techniques (natural ventilation and thermal insulation). Therefore, this study experimentally compares the seasonal impact of various soil layer configurations, integrated with natural ventilation, on improving Indoor Thermal Comfort (ITC) throughout the day in summer and winter. Field experiments were conducted using two identical validated test boxes. The results revealed that clay soil reduced Indoor Air Temperature (IAT) during the daytime in summer by up to 4.7 and 4°C for low and high soil thickness, respectively. Increasing clay soil thickness improved average IAT during the daytime in summer and winter by up to 6.49% and 2.61%, respectively. Additionally, adding thermal insulation is preferred in winter, while uninsulated soil had a slight positive effect on IAT and Indoor Relative Humidity (IRH) in summer. The use of natural ventilation at night and closed-ventilated systems during the daytime in summer and winter is recommended. Clay soil could save cooling and heating energy by up to 34.8% and 12.18%, respectively. These findings might inform designers by adjusting different GR soil parameters and the importance of natural ventilation in improving multi-seasonal thermal and energy performance. [ABSTRACT FROM AUTHOR]

Energy and exergy performance of simple vapor compression refrigeration unit is investigated experimentally with and without coupling heat exchanger of phase change material before the condenser. The hot outside air is cooled before entering the condenser throughout the day by flowing over the cooled phase change material structure that previously solidified during nighttime. Phase change material SP24 is employed because its melting/freezing range is suitable for most selected countries' climates. An experimental set‐up of an air‐phase change material heat exchanger coupled with the unit is constructed to examine its performance, including pressure–enthalpy curve, coefficient of performance, exergy performance, and power consumption including inflow air temperatures and flow rates impacts. Results affirm that the coefficient of performance, cooling capacity, power usage, and exergy destruction are improved by using phase change material. Compared to the unmodified unit, the maximum percentage of saved power and exergy destruction enhancement for the modified refrigeration unit with phase change material is about 8.8% and 10%, respectively. The maximum coefficient of performance and exergy efficiency rise is about 15.1% and 14.2%, respectively. Increasing the temperature differential across the phase change material heat exchanger, either by increasing inlet temperature or decreasing airflow, enhances the refrigeration unit power saving. [ABSTRACT FROM AUTHOR]