Ceiling radiant cooling panel (CRCP) systems are being increasingly applied to commercial buildings due to their high thermal comfort level and energy efficiency. It is recommended that CRCP systems should be operated at a relatively high chilled water temperature to prevent condensation and save energy. However, even though a high chilled water temperature is effective for achieving condensation-free operation and high chiller efficiency, it can lead to insufficient cooling capacity. In this study, a method of enhancing the cooling capacity of CRCP systems was investigated through mock-up chamber tests. The open-type installation of CRCPs and the combination of air circulators were used to enhance the cooling capacity and energy performance of CRCP systems. Experimental results showed that compared to a conventional CRCP system, the cooling capacity of an open-type CRCP system with air circulators increased by up to 26.2%, and its cooling energy consumption decreased by up to 26.4%. Additionally, the open-type CRCP system with air circulators reduced the difference between the room air temperature and mean chilled water temperature. Thus, the proposed system can operate at a relatively high chilled water temperature, which is effective for reducing condensation risk and cooling energy consumption.

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Light shelves provide a function to control direct sunlight and introduce daylight into indoor spaces. Also, chilled water flowing in the light shelf can mitigate local cooling demands in perimeter zones. Therefore, in this study, a thermally activated light shelf (TALS) system was proposed, and the TALS’s radiative cooling capacity was evaluated. To do this, a mock-up chamber was developed using prototypes of TALS systems based on panel configurations. It is included: ‘Insulated’ (INS), ‘Air layer’ (ARL), and ‘Air layer with fans’ (ARF), which were designed to increase thermal insulation, natural convection, and forced convection in the TALS panels, respectively. The experiment showed that the ARL and ARF increased cooling capacity by 29% and 57% compared to the INS. Natural convective heat transfer and fan-forced airflow in the TALS's air cavity contributed to improving cooling capacity. With the INS and ARL, the air temperature was recorded at 28.6°C, which requires additional space cooling. The ARF reduced air temperature up to 2.0°C because the TALS cavity fans expedited convective heat transfer and mixing air between the cavity and test chamber. The results of this study could be used to estimate TALS cooling capacity and propose an optimal design in buildings.