A new heat sink for cooling photovoltaic systems using a honeycomb heat sink filled with multiple phase change materials

The electrical efficiency of photovoltaic (PV) cells is significantly influenced by their operating temperature. As the temperature increases, the power output decreases; therefore, effective thermal management is essential to maintain conversion efficiency and maximize energy production. In this study, a PV cell is integrated with a proposed honeycomb structure comprising ten uniformly distributed hexagonal cells. This structure functions as a heat sink and incorporates multiple phase change materials (PCMs), specifically RT-35 and RT-27, through the heat flow path. The thermal performance of a conventional case, where the PCM enclosure is attached to the backside of the PV cell, was compared with that of the proposed honeycomb heat-sink design while maintaining the same PCM volume in both configurations. To achieve this, the dimensions of the hexagonal cells were adjusted accordingly. The numerical model was validated against experimental data from the literature and showed excellent agreement. Simulations were then performed at tilt angles of 30°, 60°, and 90° to assess the PV cell temperature, electrical efficiency, and thermal regulation duration of the proposed design. Among the investigated configurations, the RT-35/RT-27 arrangement (RT-35 in triangular regions and RT-27 in hexagonal capsules) showed the optimal performance. Compared to the conventional case, the proposed configuration achieved a roughly 6.72% enhancement in electrical efficiency, with reductions in PV cell temperature of 29.6%, 31%, and 32.3% at tilt angles of 90°, 60°, and 30°, respectively, during the thermal management period. These findings demonstrate that the proposed design significantly enhances the thermal regulation and electrical performance of photovoltaic systems.