Japanese oil group Idemitsu Kosan inaugurated the Himeji Power Storage Station on October 10, a 15-megawatt (MW), 48-megawatt-hour (MWh) energy storage facility built on the former Idemitsu refinery site in Hyogo. This is the company’s first large-scale energy storage project, as it seeks a position in Japan’s emerging battery storage market.
Public funding and industrial execution
The project received a ¥1.6bn (around $10.75mn) subsidy under the Japanese Ministry of Economy, Trade and Industry’s (METI) 2022 supplementary budget for grid-scale storage infrastructure. Construction was carried out by JGC Holdings and began in August 2023. The facility is owned by a dedicated entity, Himeji Chikudensho LLC, established to hold and operate the asset.
Division of roles among partners
Idemitsu Kosan holds a 51% stake and will handle the asset’s participation in wholesale, balancing, and capacity markets, in addition to maintenance operations. Nagase & Co. owns 22% and provides engineering support for the battery systems. Renova, also holding 22%, managed the engineering and leads the project company. SMFL Mirai Partners, which structured the financing, owns the remaining 5%.
First step into grid storage
According to Idemitsu Kosan, the project aims to establish a business model around battery storage, drawing on its experience in electricity generation and renewables. The company currently holds stakes in over 100MW of solar power plants, along with several onshore wind, biomass, and thermal projects.
The group has not announced any other battery storage projects currently under development.
