Integrate exergy costs and carbon reduction policy in order to optimize the sustainability development of coal supply chains in uncertain conditions

Abstract

The coal supply chain in developing countries is supposed to have the lowest cost overall; however, in terms of sustainability (social, economic, and environmental aspects) and considering Joules rather than monetary objectives, does this assumption remain accurate? This research develops a sustainable model for coal supply chain in five countries by integrating exergy costs and carbon tax policy using the extended exergy accounting (EEA) method under an uncertain environment. This sustainable model is a single vendor multi-buyer economic order quantity (EOQ) model for coal supply chain with the objective of the least total exergy with the maximum carbon and imperfect quality items decrease. Additionally, some realistic suppositions such as waste disposal to the environment, the obtainable budget of buyers and stockout in the model are considered. Following this, four metaheuristic algorithms, such as WOA, GA, ACO, and SA, are suggested to solve the model, and their results are validated by the exact method (GAMS). Finally, to improve the model's sustainability, a sensitivity analysis with different exergy values is offered for coal supply chain in each country. According to the results, coal supply chains in Canada and Germany have better sustainability performance (in Joules) than Iran and Turkey.