• Develops a region energy system model to investigate roles of flexibility. • Investing in local generation and flexibility is cost-efficient to meet regional demand. • Stationary batteries are cost-effective to be deployed in generation and transfer nodes. • Storage technologies are sized to tackle different durations of variations. Flexibility in energy systems entails measures that support the efficient integration of weather-dependent electricity generation (e.g., wind and solar). This paper investigates the roles of flexibility measures, such as stationary batteries, vehicle-to-grid (V2G), electricity trade, and flexible production of hydrogen in a future regional electricity grid. The study employs the RESYST techno-economic model, which co-optimises investment in and dispatch of generation, storage, and conversion technologies such as electrolysis and heat pumps, with high spatial and temporal resolutions, with test case a region of western Sweden in Year 2050. The results reveal that it is cost-efficient to meet most of the demand using local generation together with storage units as flexibility measures. Stationary batteries and V2G compete in serving similar roles in a regional electricity system, where the deployment of batteries diminishes as diffusion of V2G increases, yet batteries prevail in areas with large deployments of local generation (wind and solar) and access to transfer electricity towards other areas. Batteries and V2G alleviates local congestion points and manage local variations within the region, as they can be discharged during times of low local generation, then to deliver electricity to other parts of the region. With high-level deployment of wind and solar power and the possibility to trade with other parts of the region, flexible hydrogen production is cost-effective, despite the additional costs for overcapacity and storage that it entails.
Prianto et al. (2026) studied this question.