Sahelian developing countries depend heavily on oil-import for the supply of their increasing energy demand. This setup leads to an imbalance in the balance of payment, an increase of debt and budget asphyxia, whereas renewable resources are widely and abundantly available. The objective of this paper is to carry out a feasibility analysis of off-grid stand-alone renewable technology generation system for some remote rural areas in one Sahelian country. A survey conducted in 2006, within the framework of microgrids project, in rural areas located in three different regions in Senegal (Thies, Kaolack and Fatick) permits determination of demand estimations. Two reference technologies are chosen, namely a solar photovoltaic (PV) system of 130 Wc for solar endowment and a wind turbine of 150 W for wind speed. Taking into account the life-cycle-cost and the environmental externalities costs, our results show that the levelized electricity costs of PV technology are lower than the cost of energy from the grid extension for all these three regions. Thus, decentralized PV technologies are cost-competitive in comparison to a grid extension for these remote rural areas. For wind technology viabilities results are attained with a requirement demand lower than 7. 47 KWh/year for Thies and 7.884 KWh/year for the two remaining areas, namely Kaolack and Fatick. The additional advantage of the proposed methodology is that it allows the environmental valuation of energy generated from non-renewable resource.