Degradation Assessment of a Photovoltaic Plant After Several Years of Operation

Abstract

This present study is an evaluation of the degradation of the electric characteristics of the photovoltaic modules of a solar power plant settled in the CERER after 3.3 years of operation. The Center of Studies and Researches on Renewable energy is an institute of Cheikh Anta Diop University of Dakar. It is situated in the district of Hann Bel Air. Since a few years; the CERER contributed a lot research of solutions to the problems of development bound to the energy and to the environment it is all the interest of this evaluation which aims at the improvement and at the planning of the photovoltaic systems. It is what explains the study of this evaluation which was proposed. Moreover the evaluation of the degradation of the solar power plant is centered on the global system, constituted by 18 polycristallins, all identical modules of type STP175P-1, connected in series. So we calculated the rates of degradation of the electric characteristics of modules after a few years of operation such as the characteristics I-V and P-V, the maximal power (Pmax), the maximal tension (Vmax), the maximal current (Imax), the tension in opened circuit (Voc), the current of short circuit (Icc) and the fill factor (FF) in the standard conditions of test (STC). The study of this global system allowed to take up respectively the rates of annual degradation of 2.01% / year, 1.69% / year, 0.34% / year, 1.1% / year and 0.9% / year for the power, the maximal tension, the maximal current, the current of short circuit, the tension in open circuit and the factor (mailman) of shape. We observed that the most degraded performances are: the maximal power, the maximal current, the current of short circuit and the fill factor; while the tension with open circuit shows no significant degradation during these 3.3 years of operation.