Zineb Edfouf

Soiling deposition on solar mirrors exposed in Morocco

Surface soiling deposition is a very common phenomenon that alters the optical properties of solar mirrors during their operation in thermodynamic solar power plants CSP. This degradation can often be recovered through suitable cleaning process. Soiling deposition is function of several parameters related to the nature of the surface, deposits and environmental conditions in the installation sites. In order to study the variation of soiling rate based on these parameters, a study was conducted on mirrors samples exposed in two different sites in Morocco. The obtained results showed that soiling depositions on mirrors samples exposed in the seaside site contain salt and sand particles while those collected from samples of desert site contain only sand particles. The size of collected particles was also characterized during sampling period. It was shown that the variation of soiling rate is highly affected by environmental conditions while it is directly related to the exhibition season. In addition, rainfa...

Comparison of two methods used to evaluate the aggressivity of a Moroccan marine site on solar mirrors

Durability of solar mirrors under Moroccan marine environment has been studied for a period of 3 years. At this period, a study was focused on marine atmosphere zone and studied the deposition of chlorides on wet candle device and its relation with chlorides accumulated into mirrors surface. Four glass mirror types were placed at exposure racks located at a marine outdoor site near the sea. Periodically, salts deposited on mirrors surface and those captured on wet candle device were recovered and its salinity was monitored by using a portable conductivity meter from VWR EC300. The data collected showed that the marine salt deposition is significant regarding the short distance from the seashore. Relationships between the concentration of marine salts and site meteorological conditions are established. Comparison between wet candle sensor and concrete samples methods were discussed. Finally, this study shows that chloride deposition plays an important role as an environmental indicator on service-life analysis of solar mirrors in marine atmosphere zone and it can provide important data for the design and maintenance of CSP infrastructures in such environments.

Study of sprayed CZTS thin films containing various copper content

By ultrasonic spray, we have deposited CZTS films on Mo coated substrates. A sulfurization treatment was systematically performed under Argon atmosphere at 500 °C for one hour. Copper content effect of CZTS thin films of about 1 µm was studied by X-ray diffraction, Raman spectroscopy and optical transmittance measurements. The films exhibited the kesterite structure despite the appearance of some secondary phases for a high and poor copper content. The gap energy value was sensitive to the copper content and ranged between 1.42 eV and 1.68 eV.

Electrochemical Lithium and sodium insertion from aqueous solutions into TiO 2 films deposited on stainless steel

Nanostructured titanium oxide thin films were fabricated directly by an anodic electrodeposition using an aqueous TiCl3 solution. Structure and morphology of thin layers of TiO2 deposited on stainless steel and annealed at different temperatures were characterized by X-ray diffraction (XRD) and microscopy techniques (SEM, AFM). Two phases of titanium oxide observed at annealing temperature 350 °C (rutile and anatase) converts after annealing at 450 °C into anatase well-crystallized phase. The grain size was of about 20-30 nm. By AFM analysis, roughness around 50 nm was observed. Cyclic voltammograms (CVs) showed that annealed titanium oxide films have exhibited reversible insertion/de-insertion of lithium ion and of sodium in LiOH or NaOH aqueous electrolyte.

Research on component materials used for Moroccan CSP power plants: Mirrors ageing and thermal storage

CSP power plants are largely planned in Morocco. However, their components are subject of weather ageing at different areas in the country and thermal storage has a very important impact on power plants operation. For this reason MAScIR foundation and CEA-LITEN collaborate on two studies concerning mirrors ageing under Moroccan weather and an improvement of thermal storage on natural rocks. In this paper, description of the methodology is done and some results are given.