Analysis of Hydrogen Storage for Seasonal Leveling of Renewable Energy Generation in Scenarios of Japan’s Generation Mix

The power sector is being decarbonized to achieve carbon neutrality in 2050, and the Group of Seven (G7) has decided to phase out coal-fired power generation by 2035. In this study, we set up coal phase-out scenarios for 2030, 2040, and 2050 and conducted a simulation analysis by unit commitment with an expanded introduction of renewable energy. In this study, we estimate the optimal capacity of hydrogen storage system (HSS) for various future supply scenarios in Japan through an inter-seasonal energy supply-demand leveling simulation. The proposed method is a time series simulation of unit commitment (UC) and inter-seasonal hydropower storage systems using mixed integer linear programming (MILP). As a result, the HSS significantly contributed to reducing the amount of Variable Renewable Energy (VRE) output suppression and effectively utilizing VRE in all future scenarios.