Experimental and numerical study on effects of additional air height and existing soil layer under the collector of solar chimney

Energy transition to clean and sustainable sources is essential to battle climate change. In this regard, the solar chimney system can be considered a promising technology if more optimization analysis is conducted. The Solar chimney system compromises three main parts: Collector, Chimney, and Turbine. Achieving improvement in collector’s performance in this system played a vital role in recent studies. In this work, the effects of additional air volume and soil layer have been investigated for a constructed pilot setup of SCPP with 12 m chimney height in 5 different conditions. The maximum velocity at the inlet of the chimney was 2.8 m/s accompanied with 68.7 °C for collector outlet temperature when 8 cm height was considered for average air height, while this amount increased by 23% when the average height was 68 cm under the collector. In addition, experimental and simulation results showed that adding a soil layer provided the possibility of thermal storage in the system which led to having 0.2 m/s airflow velocity for night beginning hours. Meanwhile, the soil layer made a minor decline in airflow velocity during day time. Also, it was found that in almost the same collector diameter, having 4 times higher height of the tower led to 13.1 times higher value of kinetic power production in the system.