Thermodynamic analysis of a solar chimney power plant system with soil heat storage

The daily electricity generation and continuous system operation of a solar chimney power plant (SCPP) highly depends on heat storage system under the collector. To investigate the thermodynamic behavior of an SCPP system throughout a daily operation cycle, an unsteady theoretical model that considers soil heat storage is developed in the present study. A performance comparison between steady (without heat storage) and unsteady (with heat storage) models is made for the first time. Different types of soil are used as heat storage materials in unsteady simulations to analyze the power output of SCPP per daily cycle. To gain a better view of the influences of soil thermal properties on the SCPP performance, simulations are conducted for the Spanish prototype under different specific heat capacity and thermal conductivity values. Considering a stable system power output, high specific heat capacity and thermal conductivity are regarded to be beneficial for an SCPP system.