Abstract: Autonomous hybrid energy systems use different energy sources such as solar and wind with backup units such as battery and diesel generators. They are economical options in areas remote from national grid. In this context the performance of the system to supply electric power in an efficient way of operation is important. The problem is uncertainty of renewable energy supply and load and also non-linear characteristics of components in the system. In this paper different schemes of autonomous energy system are described and a system suitable for rural electrification in Ethiopia has been recommended. The preferred system is hybrid system with AC coupling with possibility of grid integration if required.