Integrated optimisation of biowaste-based green hydrogen supply chains from economic, environmental, and safety perspectives

This study proposes an integrated optimisation approach for designing a biowaste-based green hydrogen supply chain (GHSC) using palm oil industrial wastes. For the first time, safety considerations are emphasised in the optimisation of biowaste-based GHSC design, alongside economic and environmental aspects. Additionally, the upstream supply chain superstructure has been revised to incorporate multi-centralised biowaste supply hubs to support streamlined waste management and resource allocation. A mixed-integer programming (MIP) model has been developed to address GHSC design, aiming to enhance profitability while reducing total carbon footprints and associated safety risks. Using a case study involving 34 palm oil mills in Malaysia, this study delves into the optimal design of a biowaste-based GHSC across various optimisation scenarios, including single- and multi-objective cases. Furthermore, the study investigates the potential of integrating technologies such as solar-powered electrolysis to augment green hydrogen supply, particularly when local biowaste resources are limited. The results demonstrate that the proposed framework effectively achieves integrated GHSC optimisation by identifying optimal resource and product distribution, as well as suitable production and storage technologies. Sensitivity analysis indicates that the integration of solar-powered electrolysis is economically feasible only if hydrogen prices exceed USD 5.36/kg H 2 .