Sumitomo Electric Industries has received an order from Kashiwazaki IR Energy for a new vanadium redox flow battery installation in Kashiwazaki City, with construction beginning following a Shinto‑style groundbreaking ceremony.
The city, historically a centre for Japan’s petroleum and nuclear industries, is now aiming to become a “decarbonized city” by expanding renewable energy adoption. Sumitomo Electric will support this transition by deploying VRFB technology designed to maximise long‑duration storage and stable energy supply.
The project is being jointly implemented by Kashiwazaki City and Kashiwazaki IR Energy under the FY2026 Program for Promoting Public Understanding of Advanced Energy Structure and Transformation. The battery system meets the JC‑STAR ★1 compliance label requirement and will provide 8,000 kWh of storage capacity when it begins operation in spring 2027. This fourth‑phase installation will bring total cumulative VRFB capacity in the city to 32,000 kWh.
During periods when renewable generation exceeds demand, surplus electricity will be stored in the VRFB and discharged when demand rises, enabling more effective use of local solar and other renewable sources. A 1,000 kW battery capable of eight hours discharge will also support cost reduction through wholesale electricity market trading.
A traditional Shinto ritual was held at the groundbreaking ceremony to pray for safe, accident‑free construction. Sumitomo Electric states it will prioritise safety throughout the project and continue promoting wider adoption of VRFBs, highlighting their safety, flame retardancy, long life, recyclability and reusability. The company aims to support local energy production and consumption and contribute to a more sustainable society.
Image: Greetings by the mayor of Kashowazaki. Credit: Sumitomo.
