• Energy Research

Many climatic conditions have a negative impact on production of photovoltaic (PV) systems, and sand dust could be one of the main reasons of degradation of PV panels. The objective of this study is to investigate the reduction in the electrical performance caused by sandstorm and the accumulation of sand dust on the photovoltaic module surface installed in the Saharan area of south Algeria (Adrar). For this purpose, four PV modules (ISO-100/24) were selected and their current-voltage characteristics were measured to evaluate the sand dust effect on their performances. Our results show that sandstorm and dust accumulation on the surface of the module reduce the performance in terms of energy and power, due to a decrease of the transmittance. Obtained outcomes show that in sandstorm periods, the particle deposition density is much higher. This study reveals that leaving PV module without any cleaning in the Saharan environmental conditions significantly reduces PV power output, in addition to the presence of the shading mismatch effects in case of partial cleaning.

This work presents an experimental comparative investigation between Maximum power point tracking control methods used in variable speed wind turbines. In order to enhance the efficiency of the wind turbine system, the maximum power point tracking control has been applied for extracting and exploiting the maximum available wind power. Furthermore, two maximum power point tracking controls have been analyzed, developed, and investigated in real-time using Dspace. The first was optimal torque control without speed control, whereas the second was with speed control. The maximum power point tracking control performance comparison has been performed in a real-time experimental validation to illustrate the advantages of these control on the real wind energy system. The results have been achieved and discussed, where the power efficiency improvements appeared in the transit time and in the steady-state as well. In addition, the proposed optimal torque control for maximum power point tracking with speed control decreased the response time and oscillations, while it increased the power to an interval of 12,5% to 75% compared to that of strategy without speed control in the steady-state and transit state, respectively.

Abstract The main objective of this study is to investigate the impact of climatic conditions on the performance of photovoltaic modules installed in the desert region in south of Algeria. Firstly, the performance of ISOFOTON 100 module under daily weather conditions is evaluated. Next, the effects of partial shading and accumulation of sand dust for a period of two months on power loss and the current–voltage characteristics of photovoltaic modules are examined. Finally, the visual inspection of the degradation of the UDTS 50 modules such as discoloration of encapsulant and delamination show the influence of high temperature and the other climatic factors in the Saharan environment after a long time exposure of more than 10 years observed in the field at the Unit of Research in Renewable energy URERMS Adrar. The performance degradation is also assessed using (I–V and P–V) curves normalized at STC condition compared with the nominal STC data given by the manufacturer. The experimental results show that the performance parameters such as maximum output current (Imax), maximum output voltage (Vmax), maximum power output (Pmax), open-circuit voltage (Voc), short-circuit current (Isc) and fill factor (FF) of UDTS 50 modules are degraded after these years of exposition.

Abstract In order to support the growth of grid-tied photovoltaic power plant implementation in the Saharan environment. A detailed assessment analysis of 28 kWp photovoltaic (PV) system installed on the rooftop of Research Unit for Renewable Energies in Saharan region (URER/MS), located in southern Algeria (Adrar), has been carried out and presented in this paper. The monitoring data of the PV system over 12 months (March 2017 to February 2018), are used to evaluate both energy efficiency and the output power losses. The collected experimental data reveal that the environmental parameters variation has a direct effect on the performance of both the energy conversion efficiency and the system losses. From the monitoring data and the performance assessment, it was found that the highest final yield is 5.3 h/day while the irradiation and the ambient temperature are 518 W/m2 and 37.9 C° respectively. The annual production injected to the grid is 45.12 MWh, with 2.4 MWh energy losses are attributed to the grid voltage rise, 1.57 MWh energy is lost due to the array and thermal capture losses and system losses. The yield values of maximum/minimum monthly average reference and array yield values were; 6.7/5.4 h/day and 5.5/3.2 h/day respectively. The annual average PV module, inverter and system efficiencies reached; 11.37%, 96.46% and 10.99%, respectively. Some parameters of measured data; are used to calculate the harvested energy and performance ratio, and then compared with other PV systems installation located in different geographical regions worldwide. Finally, we have studied the impact of the grid voltage rise on the grid-connected photovoltaic system performance on both energetic and economical levels.

Abstract Under weather conditions, the relationship between solar radiation and climatology of desert region is identified. Six models of global solar radiation are selected and studied during period of four years. This paper is based on solar radiation measurements in Research Unit in Renewable Energy in Saharan Medium (URER-MS) at various weather conditions. The Studies have shown that solar radiation can be calculated in terms of ambient temperature. Consequently, from temperature measurements, we know how much solar energy is received per unit area to estimate the solar radiation available at a given point on the Earth's surface. In addition, it was concluded that the impact of dust depending on varies quality of the soil, and the obtained results show that the model (M4) presents the best performance with an R2 value of 0.87.