Abstract:
Green ships with hybrid renewable energy systems become important resources of demand side management, when ships in port have the grid connection. Variance of electricity tariff has influenced the optimal solutions to power management. Current power management methods for stand-alone green ships cannot be applied to this new situation. To enable tariff-driven power management, a unified model is proposed for a green ship under different time-of-use (TOU) tariffs. In the proposed model, diesel generation, solar energy, and battery storage could support auxiliary power demand, and the surplus of solar energy could be sold to grid when the ship is connected to grid. A power flow dispatching problem is then formulated as the optimization of operational cost. To cope with variance of tariff, solar energy, and on-board load demand, a receding horizon control approach is employed to ensure a closed-loop control mechanism. Experimental results indicate the tariff-driven model can effectively reduce the overall cost of green ships, and the receding horizon control can improve the performance in terms of fuel consumption and greenhouse gas emission.
