Energy efficiency and environmental friendliness of the ship have become important parameters in the ship design process. Also, the International Maritime Organization is paying increasing attention to reducing the carbon footprint of maritime transport. From this aspect, special emphasis is placed on the study of ships that sail in coastal navigation, i.e. populated areas and have the best perspective to reduce the carbon footprint taking into account their operational regimes. A large number of fishing vessels also sail in coastal navigation. Therefore, the goal of this paper is a conceptual solution for the electrification of purse seiner with the purpose of increasing the energy efficiency of the ship, but also to reduce the carbon footprint. Electrification of fishing vessels is in its early stage, since in recent years electrified fishing vessels just started to be built. Analyzing the fuel consumption of a similar purse seiner and the typical operational regimes of the selected purse seiner, it was determined that there are prerequisites for the installation of a hybrid energy system that would increase the ship's energy efficiency and reduce the carbon footprint. Furthermore, the thesis offers a conceptual solution of a hybrid energy system with diesel generators and batteries and an electric motor that drives the propeller. The energy balance of the conceptual hybrid solution and operating regimes are presented. At the end, an analysis of lifetime costs was performed for the existing energy plant of the purse seiner and for the hybrid one, and the obtained results were compared.