Performance optimization of bifacial solar PV modules under varied albedo conditions

Abstract

This study addresses the knowledge gap concerning the performance optimization of bifacial solar photovoltaic (PV) modules under varying albedo conditions in Kenya. Albedo is a key factor influencing energy generation in solar applications. However, the extent of its impact in Kenya, particularly for bifacial modules, remains underexplored. With increasing interest in bifacial technology, understanding its operational efficiency in real-world scenarios is crucial, especially in tropical climates such as Kenya. The study employed an experimental research method involving systematic measurements of albedo, irradiance, and module cell temperature across multiple setups of bifacial PV modules mounted at different heights. The aim was to assess the performance variation under different ground surface reflectivity conditions. Two distinct surface types were evaluated: concrete and grass. For each surface, five experiments were conducted using mounting heights of 0 m, 0.5 m, 1.0 m, 1.5 m, and 2.0 m. The results revealed that higher albedo surfaces significantly enhance energy output, with concrete surfaces consistently outperforming grass due to their higher reflectivity. For example, at a mounting height of 2.0 m, concrete surfaces achieved a maximum power output (Pmax) of 432 W compared to 389 W on grass surfaces. Similarly, at ground level, concrete surfaces recorded 332 W, while grass surfaces yielded 325 W. Furthermore, within the same surface type, energy output increased with greater mounting height. A case of this was an energy yield of 332 Watts at ground-level mounting and 389 Watts at 2m mounting height for grass surfaces. Similarly, ground-level mounting registered 325 Watts for concrete surfaces, while 2m height registered 432 Watts. On the same note, the study established that varying mounting height significantly increases rear-side irradiance; thus, the combination of albedo and mounting height can influence the performance of bifacial PV modules. Furthermore, the developed optimization model effectively predicts performance outcomes, highlighting the importance of tailored installation strategies. These findings suggest that optimizing the installation of bifacial solar systems can lead to significant energy efficiency improvements, thereby contributing valuable insights to renewable energy and promoting sustainable energy practices. In conclusion, this study demonstrated that optimizing bifacial solar PV modules under varying albedo conditions significantly improves energy yield, especially with high-albedo surfaces like concrete and optimal mounting configurations. It recommends adopting bifacial modules with reflective surfaces, appropriate tilt angles, and mounting heights for maximum performance. Future research should focus on long-term performance data, advanced simulations, and broader environmental factors to refine predictive models and guide policy development.