Ventilation Benefits When Using Radiative Cooling Combined With Phase Change Materials (PCM) Storage In Hot Climates

Abstract

In this work, a passive system composed of a radiative cooling (RC) panel combined with two phase change material (PCM) storage tanks was integrated with the conventional air conditioning (AC) system to offset the increase in energy consumption related to the conditioning of the high temperature fresh air intake in the hot climate of Kuwait. The cooling power produced by the RC panel was used to charge the PCM storage tanks. One of these tanks was used for precooling the supplied fresh air and another for enhancing the coefficient of performance (COP) of the AC system by cooling the ambient air entering the condenser. A mathematical model was developed for the proposed system and a set of simulations was conducted for a typical Kuwaiti residence for the entire summer season extending from April to October. It was found that using tank 1 to precool the fresh air supplied to the space resulted in an increase in the fresh air intake at zero energy expenses: no ventilation load was required from the AC system. Furthermore, the use of tank 2 has led to an enhancement of 10.5 % of the COP. Thus, the overall energy consumption of the AC system was reduced by 22.3 % with respect to the conventional AC system.