考虑排放限制与航次成本的航速优化问题

Ship speed optimization for minimum sulfur dioxide emissions and fuel costs

在硫排放控制区(Sulphur Emission Control Area,SECA)及碳税背景下,为获得水路运输中船舶的最佳航速,满足排放要求同时实现航次成本最小化,以亚欧航线的集装箱船舶功率、容量等真实航行数据为基础,建立了混合整数凸成本最小化模型。该模型以单一航线的船速为决策变量,综合考虑航速与航行时间、船舶数量、燃油消耗、航次成本之间的非线性关系,并给出具体算例的数值结果以及航程内SECA所占航距和时间惩罚变化的灵敏度分析,进一步验证了模型的有效性。试验结果表明,SECA的设立可以减少全球范围内的硫排放量,但在控制碳排放量方面收效甚微。在一定时间约束下,船舶采用在SECA内适当减速,SECA外增加航速的航行策略能够有效平衡航次成本和排放量。

A mixed integer convex cost minimizing model is built to determine the optimal ship speed at which the voyage cost is kept minimum under the condition of satisfying the emission requirements.The model,with the ship speed for given shipping line as the decision variable,calculates the cost per voyage according to the nonlinear relation between the cost and the influencing variables,such as sailing time,number of ships and fuel consumption.The Asia-Europe shipping line is examined with real power and capacity data of container ships in the fleet.The sensitivity analysis is performed to check the impact of sailing distance in restricted zone and the time penalty in a voyage.Experiments show that establishing control zone is effective in sulfur emission reduction but not in carbon emission as for global total emission is concerned.Under given schedule constraint,a ship reduces speed when sailing in Sulphur Emission Control Area(SECA)and increase speed out of SECA is a reasonable strategy to get balance between the voyage cost and emission requirements.