A 3D numerical approach that incorporates the radiation model, solar load model, and a real turbine was used in this study. Variations in turbine performance with rotational speed were studied to investigate the power-regulating strategy option for solar chimney turbines. The results of simulations with a fan model and a real turbine were compared. The findings indicated that the fan model is a convenient approach to investigate the turbine pressure drop and updraft velocity in the design of solar chimney power plant (SCPP) without considering the turbine efficiency. In addition, the influences of the incident angle of sunlight on SCPP performance were investigated for the first time, and the results revealed that considering the hourly variation of the zenith angle of the sun and conducting shading calculation when predicting SCPP performance in the design and cost analysis, particularly annual performance, were necessary. (C) 2015 Elsevier Ltd. All rights reserved.