Integrated Whole-System Plan: An Electricity-Hydrogen Victorian Case Study

Large-scale green hydrogen (H-2) may be a promising avenue for decarbonising hard-to-electrify sectors and, potentially, to support a green H-2 export economy. System planners such as the Australian Energy Market Operator (AEMO) are thus called upon to assess the optimal energy infrastructure required to support such developments. This paper presents a novel optimisation framework for the integrated whole-system planning of H-2 production and electricity (including high-voltage alternating current (HVAC) and high-voltage direct current (HVDC)) and H-2 transmission infrastructure, with consideration of H-2 export. The proposed framework incorporates a network-aware unit commitment model with high temporal operational resolution as well as a quasi-dynamic formulation of H-2 flow in pipelines that can capture the linepack, which is instrumental in sizing of pipelines and in assessing their energy storage capability to manage the variability of renewable energy sources (RES). Computational tractability is achieved through the application of linearisation techniques and second-order cone relaxations of constraints describing the quasi-dynamic behaviour of gas flow in pipelines. The developed optimisation-based framework is demonstrated on a Victorian case study under the Hydrogen Superpower scenario in AEMO's 2022 Integrated System Plan.