Optimization of ground material properties for enhanced solar chimney power plant efficiency: A CFD and RSM approach

Ground thermal properties impact the efficiency and reliability of Solar Chimney Power Plants, yet the dynamic impact of these properties needs more consideration. This study addresses the optimization of SCPP efficiency by investigating the effect of ground materials properties on collector efficiency, updraft velocity, and temperature rise. To this end, we used a combined CFD and Response Surface Methodology (RSM) approach. Numerical simulations, validated against the Manzanares prototype, were performed, followed by regression modeling and material optimization using RSM. Weather data from Aswan, Egypt, spanning July 2021 to June 2024, were used to evaluate annual performance under realistic conditions. Results show that higher ground thermal conductivity and specific heat enhance system efficiency, achieving a collector efficiency of up to 39.11 % and an updraft velocity of 14.63 m/s during peak solar radiation. Optimized configurations improved updraft velocity by 4.62 % under low solar radiation and 4.22 % under high conditions, while power output increased by 17.71 % and 11.05 %, respectively. These findings highlight the important role of optimized ground properties in enhancing performance, particularly under low solar radiation conditions.