Pavement integrated photovoltaic thermal (PIPVT) system: A temporal and spatial analysis of energy and exergy performance

Abstract

Pavement integrated photovoltaic thermal (PIPVT) technology can utilize vast roads and pavements for electrical and thermal energy generation simultaneously. In this paper, a two-dimensional transient numerical model is developed for demonstrating the performance of a PIPVT system with two PIPVT modules and a 50 L water tank. With the mathematical model, the system performance is examined using simulations under three typical weather conditions, namely sunny, semi-cloudy, and cloudy. Besides, a long-term simulation is conducted in five climatic regions represented by five cities in China, including Lhasa, Harbin, Haikou, Shanghai, and Yinchuan, to study the seasonal and annual performance of PIPVT systems in different areas. From the viewpoint of both the first and second laws of thermodynamics, both energy and exergy analyses are performed for all the cases in different weathers and climatic regions. The overall energy efficiencies of sunny, semi-cloudy, and cloudy days are 33.10%, 34.74%, and 18.60%, respectively, revealing that the PIPVT system performs well on sunny days and semi-cloudy days, while the overall performance is unsatisfactory on cloudy days with extremely low solar radiation that rarely appears. Particularly, among the five climatic regions, the highland climatic region is ideal for PIPVT application with both the highest annual overall energy and exergy efficiencies of 37.89% and 14.17%, respectively. The icing phenomenon of the water in tubes arises in winter and late autumn in both the temperate monsoon climatic region and the temperate continental climatic region. The overall performance of PIPVT systems is best in western and southern China.