| Work Detail |
A team of researchers in Algeria has designed a new testbed and a novel acceleration law that accounts for both wind speed and sand density. The new methodology was tested on four PV modules and showed lifespans of up to 47 years in terms of sand impact. Scientists from Algeria have proposed a new accelerated aging testbed for PV modules and developed a novel acceleration law for sand erosion degradation. “Unlike existing models, our research introduces a law specifically designed for sand erosion, incorporating both wind speed and sand density for more accurate lifespan predictions in desert environments,” corresponding author, Abdelkader Elkharraz, told pv magazine. “One of the most detrimental factors affecting PV module reliability in desert environments is sand erosion. The constant bombardment of sand particles, driven by strong winds, can cause both mechanical and optical degradation of the module surface. This degradation manifests in several ways, including abrasion of the protective glass layer, scratching of the anti-reflective coating, and accumulation of dust and debris, all contributing to a reduction in light transmission and overall power output.” The custom testbed the team designed allows control parameters influencing sand erosion. It includes a sand feed mechanism that regulates sand density, a variable-speed fan to control wind velocity, and a rotation stage enabling exposure from all sides. The setup uses desertification zone sand, characterized by larger and irregularly shaped grains, which leads to more aggressive erosion. Four monocrystalline silicon PV modules were tested by the team; two of them were new 100 W Dinel Solaire modules, while the other two were pre-used Visel 80 W. Under test condition 1, they were blasted with a sand density of 5.8 g/m3 and a speed of 12 m/s; while under test condition 2, it was set to 10.3 g/m3 and 15 m/s, respectively. Per the team, condition 1 represented a “harsh accelerating environment,” while condition 2 represented “a more accelerating and harsher environment.” The new acceleration law, which was dubbed the Elkharraz-Boussaids Law after its developers, considers wind speed and sand density and ultimately calculates the mean time to failure (MTTF), which represents the average time until a system fails under specific operating conditions. Coupled with a fuzzy logic-based data analysis program, the model could then find the acceleration factor (AF). The AF quantifies the ratio between the degradation rate under accelerated test conditions and real-world conditions. The collected data were correlated with real-world wind data from a solar plant in Adrar, Algeria. This dataset was then used to project realistic lifespans for these modules under typical desert operating conditions,” Professor Elkharraz said. “Our model, coupled with a fuzzy logic program for data analysis, estimated a significantly longer lifespan for VISEL modules (46.8 years) compared to DINEL modules (31.6 years) in the Adrar region, Algeria. The lower annual degradation rates (0.64% vs. 1.38% for VISEL and DINEL, respectively) are consistent with existing literature and underscore the models potential for accurately predicting module lifetime in sand-prone regions.” Their findings were presented in “A novel acceleration law for sand erosion degradation of photovoltaic modules,” published in Renewable Energy. Scientists from Algerias Ahmed Draia University of Adrar, Medea University, and the Renewable Energy Development Center (CDER) have conducted the research. |
