A decision-making method for berthed electric-ships based on generalized nash game

Conventional seaports only need to provide cargo loading/unloading services to the berthed-in ships. Nowadays, due to the extensive electrification of the seaport and the growing concerns on the maritime environmental issues, the berthed-in ships are required to switch into the cold-ironing (on-shore power supply) mode to prevent the Greenhouse gas (GHG) emission. In general, each berthed-in ship may have different service requirement, i.e., cold-ironing power, cargo mass, berthed-out time and service flexibility. However, due to limited working conditions of a seaport, i.e., transmission limits, number of berth positions, cargo loading/unloading rates and so on, those service demands may not be compatible to each other. In this paper, a transactive market model is proposed to manage the real-time service demands of the berthed ships, i.e., cold-ironing power, loading/unloading cargo, expected berthed-out time. The real-time decision of each ship is determined by the clearing of the proposed transactive market according to the above real-time service requests and the service flexibility response of the ship owners. The transactive market is modelled as a Generalized Nash Game (GNG), and the case study demonstrates the validity of the proposed method.