Journal of the Korean Solar Energy Society ISSN:1598-6411(Print) 2508-3562(Online) 한국태양에너지학회 논문집

In this study, cooling performances were experimentally evaluated for a thermally activated light shelf (TALS), which was represented by integrating a light shelf with a radiant cooling panel. A full-scale test-bed was constructed to evaluate the cooling performance of the TALS in terms of the cooling energy and thermal environment. Three TALS alternatives were evaluated: the INS case wherein the insulation was filled in the TALS, the AIR case wherein the insulation was replaced by an air cavity, and the FAN case wherein small DC fans were installed in the AIR case for the enhancement of air flow. The experimental results showed that the TALS provides 11% ~ 51% additional cooling capacity of the fan coil unit (FCU) when it is utilized as an auxiliary cooling system for the FCU. It was found that the TALS can reduce the system operation time by 17.2 ~ 29.6% while it raises the chiller ΔT by up to 0.4 K, which implies a possible energy reduction due to the improved chiller efficiency. The cooling energy was reduced by 1.3% for the INS case and 2.7% for the FAN case, whereas the cooling energy was increased by 6.9% for the AIR case, because the cooled cavity air was not successfully used for space cooling. It was also deduced that the thermal environment can be improved, particularly at the perimeter zone, because the TALS can lower the radiant temperature at the perimeter zone. The application of the INS and FAN cases is proposed to improve the energy performance as well as the thermal environment in a building equipped with the TALS.