Prof. Said Ahzi
Prof. Said Ahzi, Qatar Environment and Energy Research Institute, Qatar Foundation, Qatar
The ability of photovoltaic (PV) panels to generate electricity from a natural and very vast source makes them a good choice to fulfill part of the population’s energy consumption. However, it is well established that while the PV panels offer advantages in in producing energy by converting sun light into electricity they are not yet the perfect option to produce electricity. The conversion efficiency for commercial PV modules is currently ranging between 13% and 20%. Consequently, only a small portion of the solar energy absorbed by the PV cells is converted into electricity while the remaining part is converted into heat, which leads to an increase of the PV panel temperature which in turn affects efficiency. Based on experimental analyses, various empirical relations have been established between electrical efficiency and PV panel temperature. From such relations it can be noticed that an increase of PV panel temperature leads to a decrease of electrical efficiency. Therefore, the PV panel temperature must be controlled or decreased in order to achieve a better conversion efficiency of the PV cells and thus, a better PV panel performance. In addition, thermal stresses may develop and lead to interfacial degradations that will also affect the PV panel efficiency.
In this work, we focus on the modeling and numerical simulations of the thermal behavior of PV panels. In order to determine the efficiency of the PV panel, a radiation model and an electrical model thus coupled be coupled with a thermal model. Knowing the weather conditions and the installation characteristics of the considered module, the radiation model is used to determine the amount of solar energy absorbed by the PV cell. Then the PV cell temperature is computed using a finite difference model along with different boundary conditions taken from the literature. Finally, the current-voltage curves and the power are predicted with the electrical model that is highly dependent on the temperature of the cells.
Biography of Prof. Said Ahzi
Dr. Said Ahzi received his PhD (1987) and Habilitation (1995) degrees in Physics and Mechanics and of Materials, both from the University of Metz, France. In January 2000, he joined the University of Strasbourg – France, Faculty of Physics and Engineering, as full Professor (Second Class, then First Class and then Exceptional Class). He holds an Adjunct Professor position with the School of Materials Science and Engineering at Georgia Institute of Technology, Atlanta – USA. He is an associate research member with TEMA laboratory at the University of Aveiro, Portugal. From 1995 to 2000, he held the position of Professor (Assistant Professor then Associate Professor) at the Department of Mechanical Engineering at Clemson University, SC, USA. Prior to this, he spent four years as Research Scientists/Lecturer at the Department of Applied Mechanics and Engineering Sciences at UCSD (University of California at San Diego, CA, USA) and four years as Postdoctoral Research Associate at the Department of Mechanical Engineering at MIT (Massachusetts Institute of Technology, MA, USA). He published more than 250 scientific papers in the areas of materials science and processing. The research applications of interest include: energy, environment, nanotechnology, biomedical as well as industrial applications.