Study of Salt Hydrate-based Phase Change Materials Integrated into Thermal Energy Storage System for Air Pre-cooling in Hot Climate

The cooling of lightweight buildings is a major future challenge due to the consequences of global warming. Air conditioning (AC) systems are a major energy consumer, so even small improvements in AC performance can lead to significant energy savings. This numerical study investigates the use of thermal energy storage (TES) to improve AC performance in hot climates. TES is a technology that shows promise in meeting the rising energy demand while reducing greenhouse gas emissions. Latent heat thermal energy storage (LHTES) is a specific type of TES that aims to reduce the need for excessive cooling or heating in buildings. Researchers are currently exploring the use of phase change materials (PCMs) as potential LHTES materials to enhance energy efficiency in building systems. The primary objective of this paper is to explore the application of PCMs specifically salt hydrate (CaCl2.6H2O) with a melting range of 29– 33°C in the pre-cooling of air, where they store night time ambient cooling and release it during the day to diminish peak cooling requirements. To accomplish this, a standard-size air-conditioning duct incorporated with the PCM enclosure has been modelled using ANSYS/Fluent. Results showed that a PCM-based air-pre-cooling model reduced peak cooling demand by 23% and air conditioning system capacity by 30%, achieving an 8.2°C drop in temperature at a velocity of 1 m/s. The findings of this study suggest that PCMbased TES systems are a promising technology for improving AC performance in hot environments.