Calculation of the Optical Efficiency of a Fixed-sun Mirror Field Based on a Stationary Circular Model

As the global demand for electricity continues to surge, traditional power generation methods are confronted with the challenges of resource depletion and ecological degradation. Solar energy, due to its widespread availability and non-polluting nature, has emerged as a promising alternative in the realm of power generation. Among solar energy technologies, tower-type photovoltaic power generation stands out with its stability, high rate, and maintainability, offering significant potential for development in regions rich in solar resources. This paper begins by delineating the calculation of shadow shading effect, the classification of projection types, and the methodologies for addressing shadow shading efficiency. Leveraging this foundation, the study proceeds to determine the optical efficiency of the heliostat, taking into account shadow shading efficiency, cosine efficiency, atmospheric transmittance, collector truncation efficiency, and mirror reflectivity. Ultimately, by computing the output thermal power of the heliostat mirror field on the 21st day of each month, the study arrives at the annual average optical efficiency, output power, and the annual average output thermal power per unit area of the mirror surface for the Gansu region.