The École Polytechnique Fédérale de Lausanne (EPFL), the Hassan II Institute of Agronomics and Veterinary Science (IAV) and Targa-Aid association (Rabat/Morocco) undertook a joint project to implement an electrification technique from different types of renewable sources, supplying small networks of isolated consumers.To help select the best solution among several production variants for satisfying the consumption, taking all of the constraints into account, the EPFL developed the OptElDec software, a simulation based decision support tool. This tool allows modeling consumers, energy production and storage elements. Furthermore, a priority system applied to consumers and power stations is introduced for acting on operation strategy of the production and storage elements. Thus, it gives an eloquent prediction of the performance of one production network variant.Once simulations are carried out, the decision support layer allows comparing several simulated variants regarding quantitative and qualitative criteria in order to find the optimum variant.Index Terms-rural electrification, simulation tool, renewable energies, decision support system 1-4244-0632-3/07/$20.00 ©2007 IEEE.