Optimum Routing for Dry Bulk Voyages with the Effect of an Emission Trading System: NSR vs SCR

Concerning the significant environmental emissions from the maritime sector, an Emission Trading System (ETS) is an effective market-based emission control measure. This study analyses the effect of ETS on the optimum routing between the Northern Sea Route (NSR) and Suez Canal Route (SCR), considering 174 dry bulk voyages between Asia and Europe. First, cost-, emissions- and time-saving made by voyages via NSR compared to SCR are estimated, and marginal abatement costs are estimated to identify feasible NSR voyages with an ETS. Accordingly, nearly 35, 80, and 160 voyages were cost-saving with NSR if SCR speed equals 10, 15, and 20 knots, respectively. Although all voyages save emissions with NSR if SCR speed equals 15 or 20 knots, only limited voyages save emissions via NSR if SCR speed equals 10 knots. Moreover, a much faster voyage via NSR than SCR could save more voyage costs, although it could not save emissions. However, a much shorter voyage via NSR than SCR could save more emissions, although it could not save costs. The optimization model derives over 90 feasible voyages for NSR, varied based on the free-emissions quota, icebreaker availability, navigation month, fuel prices, and types. Some voyages that were environmentally feasible but economically infeasible via NSR without an ETS were both environmentally and economically feasible with an ETS. However, if vessels slow steam via SCR, ETS would not significantly enhance NSR's feasibility. Moreover, NSR is more feasible if the maritime industry uses expensive and cleaner fuel types.针对海事领域显著的环境排放问题，排放交易体系（Emission Trading System, ETS）是一种行之有效的基于市场的排放管控措施。本研究针对亚欧之间的174个干散货航次，分析了ETS对北极东北航道（Northern Sea Route, NSR）与苏伊士运河航线（Suez Canal Route, SCR）间最优航线选择的影响。首先，本研究估算了相较于苏伊士运河航线，北极东北航道航次所节约的成本、排放量与航行时间，并通过估算边际减排成本，识别出在ETS框架下具备可行性的北极东北航道航次。据此，当苏伊士运河航线航速分别为10、15、20节时，采用北极东北航道可实现成本节约的航次数量分别约为35、80和160个。当苏伊士运河航线航速为15或20节时，所有北极东北航道航次均可实现减排；但当苏伊士运河航线航速为10节时，仅有限数量的北极东北航道航次能够实现减排。此外，尽管航速远高于苏伊士运河航线的北极东北航道航次无法实现减排，却可节约更多航行成本；而尽管航程远短于苏伊士运河航线的北极东北航道航次无法节约成本，却可实现更多减排。本优化模型基于免费排放配额、破冰船保障情况、航行月份、燃油价格与燃油类型等变量，生成了超过90个具备可行性的北极东北航道航次方案。在未实施ETS的情况下，部分北极东北航道航次仅具备环境可行性但不具备经济可行性，而在ETS框架下，这些航次可同时满足环境与经济双重可行性。不过，若航运企业采用苏伊士运河航线减速航行策略，ETS将无法显著提升北极东北航道的可行性。此外，当航运业使用价格更高且更清洁的燃油类型时，北极东北航道的可行性将更高。