Reducing Sand Deposition on Solar-Power Plants Using Windbreaks: A Numerical Study

Photovoltaic (PV) systems are widely used in desert areas. Hence, the damage due to extreme wind conditions and the power loss due to sand deposition (i.e. soiling) are the major difficulties facing such energy systems. In this work, the windbreak is introduced as a passive cost-effective applicable solution to avoid or mitigate the aforementioned problems. A detailed numerical study followed by a techno-economic assessment is performed to evaluate the effect of the windbreak on the performance of an existing PV system in a harsh dessert environment in terms of structural safety, sand deposition rate, energy output of the PV system, and financial feasibility of using the windbreak. Numerical calculations showed that windbreaks reduce wind loads by almost 100% in a distance up to 10H from the windbreak (where H represents the windbreak height), and it can be still effective up to a distance of 70H. In addition, the windbreak is effective in reducing soiling, for a typical range of sand particle diameters, at distances 3H-10H. As velocity increases, the windbreak becomes more effective in reducing soiling for larger distances. Sand deposition rate reduces with increasing windbreak height and with reducing windbreak porosity. Favorably, using windbreaks increases the PV energy yield by 1.6% annually due to the reduction of panel soiling losses. Finally, retrofitting an existing PV plant with a windbreak was not only a safeguard solution, but also found to be an economically attractive project with a reasonable return on investment.