This article presents the results obtained from the analysis of the I-V electrical characteristics of photovoltaic arrays that were tested in a region of the Sahara. Experiments were carried out at Adrar in the southern part of Algeria. The study includes the determination of the most representative parameters of the arrays by using numerical methods for the one exponential model. After having determined these parameters, they were numerically used in order to carry out the plotting of the theoretical I-V characteristics of modules for the considered environmental variables such as ambient temperature and solar irradiance. Other model (Rauschenbach's model) has also been considered in this article to make a comparison with the previous one. The study has been completed by carrying out the translation of the experimental characteristics for the standard conditions. This translation allowed the comparison to be made between the performances of tested modules. In the last part of the paper, some elements related to the degradation of arrays performances have been presented. (c) 2008 Elsevier Ltd. All rights reserved.