فائزه رمضاني

In this study, the impact of surrounding obstacles on the performance of photovoltaic (PV) modules, focusing on the shading effects caused by these obstacles, was investigated. Surrounding obstacles can significantly reduce the energy output of PV modules by casting shadows. The research aims to analyze the impact of the geometric and positional parameters of obstacles on the energy production of PV modules and to eva‎luate the accuracy of various shadow modeling methods in predicting the energy output of PV modules. To achieve this, various solar radiation and shading models were integrated with the single-diode model to develop five approaches for predicting the energy output of PV modules. These models were implemented in MATLAB, using solar irradiance and sun position data specific to northeastern Tehran. The study assumed the presence of a single obstacle with fixed geometry and a stationary position near the PV module. The parameters examined included the tilt and azimuth angles of the PV module, the obstacle's height and shape (square, circular, or triangular cross-sections), its distance from the module, and its spatial orientation relative to the module. The effects of variations in these parameters on the energy production pattern of PV modules were eva‎luated. The analysis was conducted under three scenarios: (1) eva‎luating the effects of changing the position of a rectangular cuboid obstacle around a PV module, (2) Studying the energy production pattern of a PV module by varying the geometric and positional parameters of the obstacle and the module installation parameters, and (3) Analyzing shading in a PV system. The results of the first scenario revealed that the obstacle's position plays a critical role in the extent of energy loss. Specifically, the southern obstacle caused the greatest energy loss, with some approaches predicting reductions exceeding 50%. Conversely, the northern obstacle had minimal impact, reducing energy by only 2–6%. Obstacles located to the east and west of the module caused energy losses ranging from 5.46% to 23.35%, depending on the modeling approach employed. In the third scenario, inter-row shading combined with obstacle-induced shading led to energy losses of 4.41% to 8.58% in the system. In the second scenario, the findings showed that the presence of obstacles can alter the optimal tilt and azimuth angles of PV modules. Shorter and farther-positioned obstacles had a less detrimental impact. Furthermore, the accuracy of the shading modeling approach significantly influenced the predictions, with more precise models improving energy estimation accuracy by 22%. The impact of radiation model accuracy was less pronounced, with prediction discrepancies ranging from 0.15% to 4.98%. These findings underscore the importance of accurately assessing the surroundings of PV modules and optimizing their placement and orientation prior to installation, particularly in complex urban and industrial environments where structural obstacles and their associated shadows are major factors influencing PV system performance. This research provides valuable insights for enhancing the efficiency and operation of PV systems in such environments.

فتوولتائيك , اثر سايه , توليد انرژي , مدلسازي , مطالعه پارامتريك

Photovoltaic , Shading effect , Energy production , Modeling , Parametric study

Faeze Ramezani

Dr. Mojtaba Mirhosseini