Effect of Phase Change Material on Performance of Hybrid Photovoltaic-Thermoelectric System under Low Concentration Ratio

Photovoltaic cells are the best known devices to convert solar energy into useful electrical energy, however, in the most efficient multijunction solar cells, more than half of the input solar energy converts into heat and wastes. In this experimental investigation, a thermoelectric generator, as highly reliable solid-state device, and a box containing phase change material are integrated to a concentrated triple junction solar cell in order to enhance the utilization of the solar energy. The triple junction solar cell and the thermoelectric generator are characterized by measuring the I-V-P under different solar concentrations. In order to evaluate the impact of using PCM, the obtained performance of the hybrid system and the short circuit current, open circuit voltage and maximum power for its two components are compared in steady state and transient regimes with the hybrid system without the PCM. The results indicate that enhancement of the concentration ratio has opposite impact on the efficiency of the thermoelectric generator and the triple junction solar cell. Furthermore, the phase change material box has a more considerable impact on the power generated by the thermoelectric generator than the triple junction solar cell for both regimes.