This book explores the critical issue of soiling on photovoltaic (PV) systems and its significant impact on power generation efficiency. It offers an in-depth examination of the causes, effects, and strategies to mitigate soiling in PV plants. Key features include:A thorough theoretical foundation on PV systems, solar energy resources, and the mechanisms behind soiling accumulation. A comprehensive review of cutting-edge research, summarizing global findings on soiling effects and effective cleaning methods. A detailed case study from experimental research conducted in Fortaleza, Ceará, Brazil, showcasing real-world data on the impact of soiling and the success of cleaning strategies. This book is essential resource for researchers, engineers, and renewable energy professionals seeking actionable, data-driven insights to enhance the performance and competitiveness of PV systems, particularly in semi-arid environments. By understanding how soiling affects PV efficiency, readers will be empowered to implement maintenance strategies that optimize power generation.