Abstract
The study explores the use of Waste Cooking Oils (WCOs) as Phase Change Materials (PCMs) for thermal energy storage, addressing environmental issues from improper WCO disposal. With global WCO production exceeding 190 million metric tons annually and per capita cooking oil consumption rising from 10.33 liters in 2015 to 11.58 liters in 2021, the need for sustainable solutions is evident. Previous studies have highlighted the thermal energy storage potential of WCOs, making them suitable for room cooling and thermal management applications. This research aims to enhance the thermal properties by blending waste sunflower and coconut oils with soybean oil, optimizing them for low (-20 to 5°C) and medium (5 to 40°C) temperature applications. Advanced characterization techniques are employed to evaluate the chemical composition and thermal properties of these blends. The findings indicate that blending WCOs with soybean oil significantly improves their thermal properties, including latent heat capacity, phase change temperature, and thermal stability. The optimized blends exhibit increased crystallinity and superior thermal conductivity, making them effective PCMs for thermal energy storage. The results validate the feasibility of converting WCOs into eco-friendly thermal storage materials, paving the way for scalable and sustainable energy management practices.