Cost-effective control of Roll-on/Roll-off Emission-Free Ships

This paper investigates the energy management of a roll-on/roll-off emission-free ship (RoRoEF-ship) that can carry passengers and vehicles. Fuel cells (FCs), energy storage systems (ESS), and cold-ironing (CI) are considered to be the energy resources of the ship. Moreover, the charging and discharging abilities of the electric vehicles (EVs) carried by the ship are used as an auxiliary source for managing the energy flow in the ship. In this paper we propose three cost-effective strategies to use EVs as a backup in the ship energy system based on the agreements between the ship operator and EV owners. A mixed-integer linear programming (MILP) approach is proposed to a highly efficient and cost-effective control for the energy management of the integrated solution (ship resources and EVs). The proposed model considers the non-linearity in the efficiency of FCs, power ramp-rate constraints of FCs and ESSs, and preferences of the EV owners. The proposed control model is applied to a test system and the simulation results are discussed. GAMS software is used to achieve the optimization process.