Nowadays in many countries the increase of generating capacity takes place in small units within the framework of so-called distributed power industry (distributed generation - DG, embedded generation), and among them in hybrid power systems (HPS). In this paper we present our experience of the design, build and exploitation of HPS in the Institute of Electrical Power Engineering, Warsaw University of Technology. The following major subjects are considered: the experience of exploitation of a hybrid solar - wind power plant, a solar power plant with a fuel cell, the concept of a wind power plant with a battery energy storage, the utilisation of a DC micro-grid for the integration of different electrical energy sources. (C) 2009 Elsevier Ltd. All rights reserved.