Effect of thermal energy storage layer porosity on performance of solar chimney power plant considering turbine pressure drop

Abstract

Performance of a solar chimney power plant (SCPP) is numerically investigated under the effects of turbine pressure drop, solar radiation and energy storage layer porosity. The solar chimney can be constructed on the soil with various properties and porosities as energy storage layer. In this article, the effects of soil porosity on the output power and energy efficiency of SCPP are investigated to find an appropriate porosity of soli. The results show that the output power of SCPP for each solar radiation and soil porosity becomes maximum at the optimum value of the turbine pressure drop. The efficiency of SCPP decreases and the output power of turbine increases with the increase in radiation flux. The reduction in efficiency compared to the increase in output power is negligible. In terms of energy efficiency and output power, the land with less porosity and the location with the high radiation is chosen as the most suitable place for construction of solar chimney power plant. Investigation of exergy loss from solar chimney outlet demonstrates that it is an increasing function of solar radiation and decreasing function of turbine pressure drop and soil porosity.