Research On LNG Ship Allocation Based On Reliability Evaluation

Due to the advantage of cleaning,high efficiency and marine transport convenience,with a sustainable growth of supply and demand LNG plays an increasingly important role in the global energy system.At present,China's external dependence on natural gas maintains sustainable growth,LNG import is an inevitable way for China to accelerate the construction of a clean,low-carbon,safe and efficient modern energy system.It is also an effective way to resolve environmental constraints,improve atmospheric quality and realize green and low-carbon development.It has important significance for energy-saving,emission-reduction and security of energy supply.With the increasing of LNG import in China,especially after China's LNG import enterprises have the ability to sign the LNG Sale and Purchase Agreements under FOB clauses,the important and urgent problem to be solved is that how to organize LNG shipping,so as to realize an optimum ship allocation to guarantee the economy and reliability of LNG import.In addition,with the development of LNG trade,the emergence of new trade modes has brought about the transformation of LNG shipping modes.It is urgent to study the ship allocation under different shipping modes in order to provide policy support for LNG import enterprises creating new import shipping modes.In order to better solve the problem for LNG ship allocation based on reliability evaluation,this article conducts the researches as below:(1)In terms of the evaluation for LNG shipping reliability,the article defines the shipping reliability and concludes three influencing factors as environment,technology and management.The evaluation indicators under the three influencing factors are investigated,screened and elaborated,a reliability evaluation system adapting to the characteristics of LNG shipping is established,then utilize evidential reasoning approach to evaluate the reliability of LNG shipping.According to the evaluation utility function obtained by the evidential reasoning approach,the utility function value indicates the reliability of different ships completing the shipping schedule on different routes,and lays a foundation for ship allocation research the based on reliability evaluation.(2)For the point-to-point shipping mode under the traditional LNG trade,the article sets up applicable ship allocation model,including fully time chartering and voyage chartering on the basis of time chartering,researching the relationship between the reliability of LNG shipping and the cost it brings.The influencing factors of reliability cost is introduced into the model to consider its impact on ship allocation,and to make the result of ship allocation improve the ship's reliable implementation of its schedule.The feasibility of using the utility function to calculate the reliability cost is verified by empirical analysis,which provides a reference for further research of the problem.(3)The change of LNG trade mode affects LNG shipping's organization modes and ship allocation plan.In order to adapt to the change of LNG trade mode,multimodal transport based on LNG portfolio is introduced into the ship allocation research.The ship allocation model based on LNG portfolio is established,and the reliability cost for the ship to execute shipping schedule is introduced into the model.The rationality of the model is verified by empirical analysis.In addition,by comparing with the LNG ship allocation under the traditional LNG trade mode,it is confirmed that the new ship allocation mode based on LNG portfolio improves the shipping reliability as well as reduces the shipping cost.This can provide a reference for domestic LNG import enterprises to optimize the ship allocation.