摘要： In rural areas, provision of drinking water is one of the most important requirements of living conditions, and most of these isolated areas are not connected to the electricity grid. Conventional technology solutions provided by diesel generators are costly because of high maintenance and fuel supply costs and have drawbacks related to noise and especially greenhouse gas emissions. New technological solutions provided by solar and wind water pumping systems are experiencing high growth rates in recent years. Because of their high initial capital cost, many studies on their optimal sizing have been carried out. In this paper, an optimal sizing model based on Loss of Power Supply Probability (LPSP) and Particle Swarm Optimization (PSO) is proposed. The main goal is to deal with the optimal sizing problem of hybrid PV-Wind-based water pumping system taking into account the techno-economic aspects. The developed method uses the PSO algorithm to find the optimal configuration of the studied hybrid system insuring minimum cost and satisfying a desired loss of power supply probability. A computing code is developed and a flexible graphical interface is designed.