Experimental Investigations on Cooking Oil and Erythritol as Energy Storage Mediums in Solar Cooking Applications

The Solar energy has acquired substantial popularity and demand owing to its ample availability and cost-effectiveness. To further enhance the performance of solar cookers, this study focuses on utilizing a concentric cylinder type solar cooking pot, with the inner cylinder designated for cooking loads and the outer cylinder used for energy storage. A dish-type solar concentrator suitable for household needs was used to analyze the thermal performance of the developed solar cooker, particularly during non-sunshine hours. Two different cases were experimented during this study. In case 1, sunflower oil served as both the cooking load and the energy storage medium. In contrast, case 2 utilized erythritol as the energy storage medium. The charging phase involved concentrating solar radiations on the bottom surface of the cooking pot. Following the charging process, temperature profiles and temperature differences were carefully analyzed to assess the heat retention capabilities of the cooker. The highest temperatures achieved during case 1 and case 2 were 213 and 217 °C, respectively, demonstrating their capability to cook various types of food. The presence of latent heat in erythritol resulted in a reduced temperature difference between the cooking load and the energy storage medium during the discharging period. Although case 1 showed higher thermal efficiency compared to case 2, both scenarios demonstrated the cooker's potential to retain and utilize stored heat during non-sunshine hours. This study successfully enhances the performance of solar cookers by incorporating a concentric cylinder design and an efficient energy storage mechanism.