Power Grids as the Backbone of the Energy Transition: Optimisation, Expansion, and Implementation Priorities

Abstract

Power grids are fundamental to the global energy transition because they connect expanding renewable-energy resources with the growing electricity demand arising from the electrification of transportation, buildings, and industrial processes. However, existing transmission and distribution networks increasingly face congestion, limited connection capacity, ageing infrastructure, and operational challenges associated with variable and distributed generation. This paper examines the complementary roles of grid optimization and infrastructure expansion in developing reliable, flexible, and low-carbon power systems. It evaluates advanced grid technologies, including dynamic line rating, advanced conductors, flexible AC transmission systems, digital monitoring, energy storage, demand-side flexibility, renewable-energy co-location, and long-distance interconnection. The analysis demonstrates that these measures can improve the utilization of existing assets, reduce renewable-energy curtailment, and temporarily defer selected infrastructure investments. Nevertheless, optimization cannot eliminate the need for substantial expansion of transmission lines, distribution networks, substations, transformers, and cross-border interconnectors. The paper also identifies four implementation priorities: establishing coordinated long-term grid plans, accelerating permitting and improving societal acceptance, addressing shortages of skills and critical components, and reforming financing structures. Successfully integrating these priorities will be essential for preventing grid infrastructure from becoming a major constraint on clean electrification and achieving global net-zero objectives.