Updated May 7, 2025, 4:25 pm.: This article has been updated to include additional information officially released by Kansai Electric Power.
Kansai Electric Power, its group company Kinden, and Japan Extensive Infrastructure (JEXI) will jointly develop a 99MW/396MWh battery storage facility at the former Tanagawa Power Station site in Misaki Town, Osaka Prefecture.
According to the company’s May 7, 2025, statement, Tanagawa Power Storage Station’s construction is expected to begin in June 2025, with commissioning scheduled for February 2028.
Kinden will handle engineering, procurement, and construction (EPC). Once operational, Kinden Kansai Service will be in charge of operation and maintenance (O&M) and Kanden Asset Management will be responsible for asset management. Another Kansai EPCO group company, E-Flow, will aggregate the fully-merchant asset, trading its power in the wholesale, balancing, and capacity markets.
Kansai EPCO holds 40% economic interest in the project’s special purpose company (SPC) Tanagawa Chikudensho LLC. Kinden holds a 10% interest and a fund associated with JEXI holds the remaining 50%. In addition to investments from the three companies, Mitsubishi UFJ will provide non-recourse project finance to fund a portion of the project.
The four-unit, 462MW power plant that formerly occupied the project site was decommissioned in December 2001. An adjacent two-unit, 1.2GW Tanagawa No. 2 Power Station, which was commissioned in 1977 and shut down due to aging equipment in 2005, was decommissioned in 2020. It is unclear whether the 20,000m2 BESS project site covers only the original power plant or both the older and No. 2 assets.
Kansai EPCO entered grid-scale storage with the 48MW/113MWh Kinokawa Power Storage Station in Wakayama Prefecture, which it commissioned jointly with Orix in December 2024. The company also joined forces with SPARX Group and JA Mitsui Lease to develop two 50MW/175.5MWh facilities in Sapporo City, Hokkaido, both scheduled to come online in April 2028.
Sites formerly occupied by thermal power plants are ideal for developing large-scale battery storage facilities both due to existing grid infrastructure and available space. As Japan transitions away from fossil fuels and decommissions old thermal assets, more such conversions are likely to follow.
Separately from Kansai EPCO, Chugoku Electric Power also disclosed plans to turn a site formerly occupied by an oil-fired power plant into a grid-scale storage facility. In January 2025, the company said it would enter grid-scale storage with a 10MW/30MWh project that will be built on the site of the 700MW Kudamatsu Power Station that was decommissioned in 2023.
Originally published as “Kansai EPCO plans 400MWh BESS at former Tanagawa Power Station site, eyes FY2027 COD: Nikkei.”
