Risk and Consequence Analysis of Hydrogen Refuelling Stations

With increasing global interest in the sustainable energy landscape, hydrogen has emerged as a promising solution. Its environmentally sustainable characteristics drive its widespread acceptance, particularly within the transportation and energy storage domains. However, ensuring safety, especially in critical infrastructures like hydrogen refuelling stations (HRS), is imperative to achieve hydrogen scaling targets. This issue is not only significant for Australia but also for the international community, as safe hydrogen technologies play a vital role in achieving sustainable energy goals worldwide. Hence, this thesis aims to study the aspects of hydrogen safety within HRS with a key focus on human errors as a primary contributor to accidents, addressing operational risks and safety measures critical for the reliable adoption of hydrogen technologies. 

Adopting an integrated analytical framework, this thesis investigates the impact of human errors on the safety of HRS. By synthesising different Human Reliability Analysis (HRA) techniques, it analyses the complex landscape of operational risks inherent in HRS operations. It develops a new methodology based on HEART, Bayesian Network (BN) and Best-Worst Method (BWM) to shed light on critical human factors including training, experience, and workload. This is crucial for ensuring operational safety within HRS contexts. This detailed evaluation helps with developing robust safety protocols and risk mitigation strategies that can enhance the safety and reliability of hydrogen fuel infrastructure globally. 

Simultaneously, the research employs a system dynamics approach to examine the dynamics of Human Error Probability (HEP) in maintenance tasks within HRS environments. Exploring the temporal evolution of Performance Shaping Factors (PSFs) like workload and fatigue, the system dynamics analysis offers invaluable insights into the evolving risk landscape within HRS facilities. The dynamic perspective enables the tailoring of safety management strategies to adapt to ever-changing operational conditions, enhancing operational efficiency and mitigating risks associated with human error. 

Furthermore, the thesis studies the consequences of potential hazards within HRS environments through Computational Fluid Dynamics (CFD) simulations. These simulations facilitate a detailed examination of the dispersion patterns of liquid hydrogen and associated explosion hazards under varying environmental and operational parameters. By analysing the correlated impacts of these factors, this model facilitates a deeper understanding of the spatial and temporal distribution of hazardous substances post-accident, thereby enabling more effective emergency response strategies and mitigation measures. 

Collectively, the outcomes of this thesis contribute significantly to the field of hydrogen safety by providing a robust framework for the accurate estimation of accident risks at refuelling stations. The integration of expert opinions, time-dependent risk factors, and detailed consequence modelling provides a multifaceted approach to enhancing the safety and reliability of hydrogen fuel infrastructure. This research not only advances theoretical understanding but also offers practical insights for the development of safer, more reliable hydrogen refuelling stations in the future not only in Australia but worldwide.