The Characteristics of a Solar Photovoltaic Array Under Different Shading Conditions

This module introduces learners to the real-world challenges and technical considerations related to partial shading in photovoltaic (PV) systems. Partial shading—caused by nearby buildings, trees, dust, or moving clouds—is a significant issue in solar energy generation, particularly in Mediterranean environments, where urban density and terrain variations are common.

This module is based on peer-reviewed research published by the author, which investigated the performance of photovoltaic arrays under various partial shading conditions. While the author's research serves as the foundation, the module expands upon these findings by integrating complementary insights from established literature, and practical simulation tools. This ensures a comprehensive and applied learning experience that goes beyond a single study to reflect broader technical, and environmental considerations.

The course will begin with a brief overview of partial shading phenomena, including its causes, types (static vs. dynamic), and how it influences solar energy production in real-world systems. Next, learners will explore typical PV array configurations (such as series, parallel, and series-parallel) and understand how these connection types respond differently to non-uniform irradiance. This section includes a comparative analysis of configuration performance under various shading scenarios. The module will then introduce the electrical behavior of PV arrays under shading, focusing on current-voltage (I-V) and power-voltage (P-V) characteristics, and the formation of multiple local and global peaks that affect power output and MPPT effectiveness. A key part of the module is dedicated to a practical mathematical model—derived from the author's research—for estimating global power peak reduction under different shading conditions. Learners will examine this model and apply it through simplified simulation examples. The final part of the module will present experimental validation results from a real PV testbed using polycrystalline modules, followed by regional case studies that highlight practical design insights, economic implications, and policy relevance for the Mediterranean solar market.

By the end of this module, learners will gain a clear understanding of how partial shading affects the electrical performance of photovoltaic systems and how different array configurations respond under various shading conditions. Through a combination of theoretical explanations, simulation-based modeling, and experimental validation, participants will be able to analyze power losses, identify local and global power peaks, and apply a practical mathematical model for predicting output under partial shading. The course equips learners with the knowledge and tools to design more resilient and efficient PV systems—especially in regions like the Mediterranean—where environmental and urban factors make shading an unavoidable challenge.

Upon completing this module, learners will be able to:

1. Identify the main causes and types of partial shading (static and dynamic) and explain their occurrence in Mediterranean environments.

2. Compare different PV array configurations (series, parallel, and series-parallel) in terms of their electrical performance under partial shading.

3. Analyze current-voltage (I-V) and power-voltage (P-V) curves of PV arrays to detect the presence of local and global power peaks caused by shading.

4. Apply a mathematical model to estimate the global peak power output of a partially shaded PV array.

5. Interpret the results of simulation and experimental data to assess the impact of shading patterns on PV system efficiency.

6. Recommend shading-resilient PV array designs and layout strategies suitable for urban and rural installations in the Mediterranean region.