Reducing peak energy demand using a phase change material-enhanced cooling system: An experimental approach
Alireza Riahi, Mohammad Behshad Shafii
Abstract
• Evaluating the effect of adding a PCM tank to an AC unit experimentally. • Adding PCM leads to shaving the electric peak load by about 67.02 %. • Saving of 13.16 % and 8.21 % on electricity bills and total initial costs. • Using two separate test chambers for simulating weather conditions. • Improved cooling availability by 83.04 % during peak hours with enhanced comfort. This study addresses the critical challenge of managing peak energy demand in air conditioning (AC) systems, driven by rising global energy consumption and increasing cooling needs. To tackle this issue, we investigate the integration of phase change material (PCM) thermal energy storage (TES) into conventional AC systems, aiming to enhance cooling performance and shift energy consumption from on-peak to off-peak hours. An experimental approach is adopted, evaluating the system's performance under realistic operating conditions by two separate test rooms. One for indoor unit and one for outdoor unit. The results demonstrate a significant reduction in peak cooling load demand by 67.02 %, effectively alleviating pressure on energy infrastructure during high-demand periods. Additionally, the system improves cooling availability during peak hours (12:00–19:00) by 83.04 %, ensuring better thermal comfort. However, the total daily electricity consumption increases by 5.49 % due to the energy required for TES charging. The novelty of this work lies in its comprehensive experimental assessment of the complete charging and discharging cycles of a PCM TES system, contrasting with the simulation-based studies that dominate existing literature. Furthermore, the use of water as the PCM medium offers a practical and cost-effective solution, minimizing system complexity and facilitating real-world implementation. These findings provide valuable insights into the feasibility and efficiency of PCM TES integration, offering a promising strategy for optimizing building cooling performance and reducing peak energy demand.