Master thesis consists of the definition of energy communities, where the concept and conditions for establishment, as well as the purpose and ideas of energy communities are defined. Energy activities that can be carried out in energy communities are described, namely energy production, energy storage, energy efficiency and conservation monitoring, energy sharing and trading, energy education and awareness, and energy policy and advocacy. The activity of energy production and energy storage is described in more detail with described examples. Virtual connection and communication technologies of energy communities are briefly described. The ways of organizing energy communities through organizational modules are described and examples are given. The advantages of energy communities are listed and described. The legal, social and political aspects of energy communities are presented. The procedure for planning energy communities is shown. A simulation of the energy system was carried out in the HOMER program, which shows the profitability of the implementation of renewable sources and the positive impact on the environment.