Enhancing Phase Change Characteristics of Hybrid Nanocomposites for Latent Heat Thermal Energy Storage

Thermal energy storage systems store intermittent solar energy to supply heat during non-solar hours. However, they often exhibit poor thermal conductivity, hindering efficient energy storage and release. The purpose of this study is to enhance the phase change characteristics of a paraffin wax-based latent heat energy storage system using a hybrid nanocomposite while increasing its thermal conductivity. Present heat storage systems integrate nanomaterials into a phase change material (paraffin wax) for faster energy storage and release in the form of heat. Steatite and copper oxide are chosen as nanomaterial additives in this experimental investigation. The charging and discharging characteristics of latent heat energy storage systems are studied using four different cases involving pure paraffin wax (case 1), paraffin wax with 10 wt% steatite (case 2), paraffin wax with 10 wt% copper oxide (case 3), and 5 wt% steatite with 5 wt% copper oxide (case 4). The charging and discharging rates were studied. The solidification rate of the nanocomposite improved with the addition of nanomaterials. The paraffin wax with 10 wt% copper oxide (case 3) outperformed the other cases, showing the best heat transfer ability and achieving an overall fusion time of 90 min. Case 3 was found to be the most thermally effective among the other cases. A significant finding of this study is the enhanced thermal performance of paraffin wax-based LHS systems using CuO and steatite nanocomposites, which hold great potential for practical applications. These include solar thermal systems, where efficient energy storage is critical, and industrial heat recovery systems, where optimizing heat transfer and storage can significantly improve energy utilization and sustainability.