Supercooling Behavior of Water-Based Solution with Propylene Glycol

Thermal energy storage using phase change material (PCM) is considered a promising technology for future energy needs due to its low-cost and high storage capacity under isothermal conditions. Supercooling of phase change materials (PCM) during the transition process from liquid to solid is a major problem in thermal energy storage, which reduces energy efficiency and exacerbates energy wastage. This study focuses on the supercooling characteristics of PCM under heterogeneous nucleation, which provides a new idea to investigate the effect of nucleating agents on the supercooling rate of aqueous solutions. Understanding, predicting, and, where possible, preventing, or at least reducing, supercooling is particularly important for latent heat thermal energy storage systems, as the temperature differences within them must be small to achieve higher efficiencies. Water is the most popular PCM today because it has good characteristics despite high supercooling. Various PCM samples were prepared and tested in this study to reduce water supercooling. The sample comprises water and propylene glycol solution in various percentages (10/90, 20/80, and 30/70). The t-history method is applied to test the samples. The results showed that the water supercooling decreased with the increase in the percentage of propylene glycol solution in water, from 10 degrees to 6, 4, and 2 degrees, respectively, making it suitable for cooling applications.