Experimental and theoretical research on thermal and electrical performance of a novel building envelope integrated photovoltaic and thermal thermoelectric in heating season

The thermoelectric (TE) wall integrates TE technology into building walls to actively regulate indoor heat. However, the heat transfer efficiency of existing thermoelectric walls, which utilize radiation and convection, is comparatively low. This paper establishes a novel Building Integrated Photovoltaic/Thermal-Thermoelectric Cooling Wall System (BIPV/T-TE), which uses water cooling and forced convection to enhance photovoltaic conversion efficiency and system COP, and provides heating to the indoor. The system's simulation model was developed, experimentally validated, and its performance during the heating season was evaluated. The study investigates the impact of four factors on the performance of the BIPV/T-TE system and compares its performance with different enclosures. The results show that the average COP of the system during the heating season ranges from 1.47 to 1.66, with higher COP at higher outdoor irradiation. Although the BIPV/T-TE system may cause heat loss in the room at certain times, it achieves an average increase of 23.2 % in power generation compared to the BIPV system . Reducing the water flow rate, the number of TE modules (TEMs), and current significantly enhances system efficiency. Under conditions of 0.3 L/min water flow rate, one TEM group, and 1 A current, the system demonstrates excellent operational performance.