Experimental and numerical study on photovoltaic thermoelectric heat storage system based on phase change temperature control

To improve the thermal and electrical performance of photovoltaic (PV) systems, a novel system was proposed, in which the PV panel, phase change material (PCM), thermoelectric (TE), and thermal collection devices (PVPCM-TEG-T) were combined. The experimental device of the PV-PCM-TEG-T system was put up, and its electrical and thermal characteristic was experimentally studied by comparing it with the standard PV panel on the condition of 3-hour radiation and 3-hour non-radiation. A heat transfer numerical model of the PV-PCM-TEG-T system is established and verified by experiments. The comparison of the PV-PCM-TEG-T system and standard PV panel and the effects of PCM thicknesses, and melting temperatures on the temperature of photovoltaic devices were numerically analyzed in 24-hour operating conditions. The results show that under an experimental condition of 3-hour solar radiance of 800 W/m2 and 3-hour non-radiance, the novel system has better temperature control performance, which could increase the PV panel's output power and power generation efficiency by 10.4 % and 1.9 % respectively. Under 24-hour simulation conditions, the temperature of the novel system is significantly lower than that of the standard PV panel, with a maximum temperature difference of 10.1 degrees C. The PVPCM-TEG-T system with thicker PCM has the same temperature as the system with thinner PCM, but higher TE power generation. And the temperature control is better with the lower PCM melting point. This study has a good promoting effect on the efficient utilization of solar energy.