This paper presents a comprehensive review regarding the published work related to the effect of dust on the performance of photovoltaic panels in the Middle East and North Africa region as well as the Far East region. The review thoroughly discusses the problem of dust accumulation on the surface of photovoltaic panels and the severity of the problem. Moreover, a survey of the most advanced cleaning techniques is presented, and their applicability is evaluated. There are plenty of techniques that have been used to remove the dust accumulated on the surface of PV panels, and these include manual and self-cleaning methods. However, it is concluded from the presented review that there is a strong need for developing new cleaning methods especially for the Middle East and North Africa region, which do not consume water and have low capital and operational costs with less human intervention, especially for hot, arid, and dusty regions.

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Dust accumulation on photovoltaic panels represents a major challenge for the operation of solar panels especially in the regions known by their high rate of dust and low frequency of rain. The objective of this study is to minimize dust accumulation on PV panels operating street light posts using dust shields. A novel dust shield having the same width of the panel, and subtending an angle of 120° with the panel, is proposed for dust mitigation. Numerical simulations are carried out to evaluate the influence of the dust shield on dust accumulation over the panel’s surface. It is found that using a dust shield decreases the dust deposition rate by more than 44%. Moreover, extending the panel’s surface at the lower edge with an extension plate together with the dust shield decreases the dust deposition rate better than using a dust shield only. Also, the effect of adding an air gap between the shield and the added extension plate is investigated, and it is found that the air gap induces air drafts over the panel’s surface, which acts as an air barrier that obstructs the approach of dust particles to the panel’s surface. These drafts get stronger as the air gap thickness increases, accordingly, less particles deposit on the panel. Finally, it is found that using a dust shield with a length smaller than the panel’s length in addition to an extension plate together and increasing the thickness of the air gap is an effective and efficient solution for dust mitigation, such that the percentage decrease in the dust deposition rate that might be more than 88%.

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The Fresnel system can achieve high electrical energy yield compared to the traditional photovoltaic (PV) panel techniques due to the concentration of solar energy. However, this huge energy might cause overheating of the PV panel. The objective of this research is to mathematically model a linear Fresnel system that is cooled by either spraying the PV panel by tap water or chilled water, in order to determine the maximum possible concentration ratio, which is called the critical concentration ratio. Then, the model is further used to study the effect of cooling on the PV panel in real life operating conditions in two cities; the first one is a hot city which is Cairo, Egypt, and the other one is a cold city which is Stuttgart, Germany. The objective is to find out the Critical concentration ratio (Cr) at which the maximum energy output from the system can occur as a function of the operating conditions. The results of this study show that cooling of the PV panels using chilled water system is not feasible. Therefore, in order to improve the feasibility, a low energy cooling system should be adopted. Such system may include spraying tap water on the PV panels, recollecting the water and cooling it naturally underground and finally spraying it again on the panels. The maximum output energy has increased by approximately 75%, compared to the nocooling case, due to water spraying, which indicates the feasibility of water spraying in Fresnel systems.

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