Remote areas are often powered by oversized diesel generators, resulting in high investment and operating costs and significant greenhouse gas emissions. To address this issue, a methodology for optimal sizing of mini-hybrid PV/diesel/battery power plants, using HOMER software, has been presented. A case study was conducted to analyze a real hybridization project of a multi-generator diesel power plant located in the village of Moulay Lahcen, Tamanrasset, Algeria. The study aims to reduce the net present cost, the Levelized energy cost, and CO2 emissions. A comparison of different configurations of hybrid mini-power plants, with and without storage, has been conducted. The results show that a hybrid PV/diesel/battery system in AC/DC switched configuration is a reliable, cost-effective, and environmentally friendly option for the sustainable electrification of the studied remote areas. This configuration has the lowest net present cost (NPC) of $483443, a Levelized cost of energy (LCOE) of $0.132/kWh, a fuel consumption of 49868 liters/year and CO2 emissions of 130.434 tons/year. A sensitivity analysis of several parameters influencing the design of the studied systems was also carried out. This analysis highlighted that the price of fuel is one of the parameters that most influences the choice of the optimal hybrid system.