AbstractThepaper presents a new concept for the optimal design of autonomous energy supply systems based on a photovoltaic plant, a battery and a hydrogen storage path (PV-battery-H2-hybrid system) with the focus on the optimal sizing of therated power and the capacity of all system components. For this purpose a multi-criteria objective function (combining installation and operating costsas well as componentlifetime) and multiple constrains (e.g. security of supply) are considered. The basic characteristics and the complexity of the resulting solutionspace of the optimization problem are described as a function of the sizing and energy management parameters. For the minimization of the objective function a particle swarm algorithm was employed. The paper presents the implementation of the algorithm and simulation results for an example hybrid system configuration. The behaviour of the particle swarm is investigated for different scenarios. Results demonstrate excellent computational speed and accuracy compared to other optimization methods.