Experimental study of electricity generation from solar energy using organic phase change materials and thermoelectric generator

The study investigates using edible oils (ostrich, mutton, beef, coconut) as natural phase change materials for solar energy absorption and storage. Exposed to 900 W/m² direct radiation by a solar simulator, these materials harness captured energy at a specific depth to generate electricity through a thermoelectric device. The experimental results showed that coconut oil exhibits the highest thermal energy storage efficiency among others, measuring at 39 %, while mutton tallow shows the lowest performance at 16.59 %. Additionally, the performance of a system employing coconut oil as the best material, in combination with iron oxide nanoparticles and carbonized sawdust (CS) was experimentally evaluated at different mass fractions (0.3 %, 0.6 %, and 0.9 %) to enhance thermal conductivity and sunlight absorption. The carbonized sawdust and its nanoparticles increased the thermal energy storage efficiency of the system by 62 % and 53 %, respectively. Moreover, the stored exergy by the phase change materials indicates that coconut oil and beef tallow had the highest and lowest exergy efficiencies of 6.3 % and 3.3 %, respectively. The combination of coconut oil with iron oxide nanoparticles and carbonized sawdust leads to 10 % and 7.9 % increased exergy efficiencies respectively.