Reviewing sector coupling in offshore energy system integration modelling: the North Sea context

Offshore energy system integration is particularly important for realising a rapid and cost-effective low-carbon energy transition in the North Sea region. Effective implementation of strategies that require collaboration between countries, developers and operators must be underpinned by robust and comprehensive modelling results. Intra-system interactions and diversity of sectors needed to facilitate the energy transition must be adequately captured within whole-system models. Historically, consideration of the offshore energy environment within macro-scale models has been supplementary to the onshore system. However, increased deployment of offshore wind, focus on geological storage for energy security, and technological development and investment in hydrogen and carbon storage projects highlights the importance of expanding the role of the offshore system within modelling. This study presents a comprehensive investigation of energy system integration challenges within offshore system modelling, and how these define the requirements of the employed methodology. The findings suggest large-scale offshore system modelling studies typically include few energy vectors, limited spatial resolution and simplified network flow characteristics. Despite the North Sea focus, these challenges reflect fundamental barriers within large-scale offshore energy system modelling and thus extend to similar offshore contexts globally. Key approaches are identified to maximise sectoral and technological diversity, while maintaining sufficient temporal and spatial resolution to suitably represent the evolving offshore system, are identified. We make concrete suggestions for future work in this field, based on identified best practice among the reviewed literature. • The role of offshore energy system integration within energy system modelling is investigated. • Less than a quarter of the investigated literature considers integration of more than two energy sectors. • Modelling energy storage and novel carriers is essential for informing offshore energy transition decisions. • Models that incorporate technical and spatial constraints are better able to inform policy.