The role of spatial resolution in global electricity systems modelling

We perform a global case study to assess the implications of spatial resolution in electricity systems modelling. The global model PLEXOS-World is used to optimize the long-term capacity expansion and short-term operation of a global net-zero electricity system under alternative spatial resolution assumptions. We find that spatial resolution assumptions have a large influence on electricity system operational and planning decisions regarding the integration of variable renewables as well as the utilization of transmission infrastructure and other flexibility providers. Furthermore, challenges with respect to spatial aggregation arise with respect to data accessibility and spatial aggregation methods, and there are trade-offs between increasing spatial resolution and computational performance. A question-based framework is provided that can assist modellers in selecting the appropriate spatial extent and resolution.