This article studies the development of integrated electricity and electrolytic hydrogen production systems in Finland, Sweden, and Norway under capital-cost uncertainty. We contribute to the existing literature by conducting a comprehensive scenario analysis with alternative capital-cost pathways for wind, solar PV, nuclear power, and hydrogen technologies, while explicitly incorporating weather resilience in system optimisation. Applying an energy system model, we optimise capacity expansion and energy dispatch across the power and hydrogen sectors through 2060. The model meets growing electricity demand with increasing wind and solar installations and a wide set of flexibility measures in all scenarios. Wind becomes the dominant source of power generation, although solar PV gains importance under optimistic capital-cost scenarios. New nuclear capacity is not expanded in any scenario, but long-term operation investments are made in full. Electrolysers operate with relatively constant loads in most scenarios, supported by dispatchable generation, but provide increasing demand response with declining capital-cost assumptions. Seasonal and inter-annual balancing for the power sector is mainly provided by biogas turbines, while lithium-ion batteries become increasingly important for providing short-term flexibility. Finally, we find that expanding inter-regional electricity transmission is cost-effective for flexibility and leveraging regional weather variability, and that hydrogen transmission gains competitiveness with higher assumed capital costs for electrolysers and hydrogen storage. • Expansion of wind and solar is found to be economic compared to nuclear power. • Biogas turbines provide backup power and ensure inter-annual weather-resilience. • Dispatchable power supports wind and solar in cost-optimal hydrogen production. • Electricity and hydrogen transmission enable optimal utilisation of wind and solar.
Tarvainen et al. (Wed,) studied this question.