28 April 2026

Sumitomo Electric Industries, Ltd. (Sumitomo Electric) today announced that its vanadium redox flow battery (VRFB) has been selected by Hokkaido Electric Power Network, Inc. (Hokkaido Electric Power Network) through a solicitation process to supply a stationary battery storage system to support the expansion of grid interconnection for wind power.
For this project, a 33 MWh VRFB (11 MW × 3 hours) will be installed at Hokkaido Electric Power Network’s Minami-Hayakita Substation. The project is being carried out with the understanding and cooperation of Abira Town in Hokkaido, where the substation is located. The town has declared its commitment to becoming a “Zero Carbon City.” The project is scheduled for completion by the end of May 2029. Additionally, Sumitomo Electric will enter into a long-term service agreement (LTSA) covering operations and maintenance (O&M) for a 20-year period following project completion, as well as decommissioning at end of operational life, thereby establishing a sustainable lifecycle management framework.

Hokkaido Electric Power Network conducted a solicitation for wind power developers to share the costs of grid-side battery storage under the "Solicitation Process for Wind Power Generation Utilizing Grid-Side Batteries (Phase I Remaining Capacity)". Through this initiative, 97,000 kW of wind power capacity has been approved for grid interconnection. Sumitomo Electric’s VRFB has been selected through a recent tender for grid-side battery storage, which is required to enable the grid interconnection of these wind power projects.
Sumitomo Electric’s VRFB has been selected based on its long service life, high level of safety, and environmental performance, as well as its proven track record of supplying and operating large-scale energy storage systems, including prior installations for the Hokkaido Electric Power Network.

Sumitomo Electric will continue to work toward realizing a sustainable society through its VRFB technology, aiming to contribute to the flexible management of electricity supply and demand, the maximization of renewable energy utilization, and the reduction of greenhouse gas emissions.

■Key Features of Vanadium Redox Flow Batteries

	High Level of Safety (Minimal Fire Risk) The electrolyte is non-flammable and all system components are made of flame-retardant materials.
	Long life Due to its fundamental charge/discharge mechanism, there is no degradation of electrolyte or electrodes, and the number of charge-discharge cycles does not accelerate degradation. The system can be operated for long periods regardless of operating method.
	Environmentally Friendly The electrolyte can be reused, a practice already proven in the field. Additionally, with proper material separation, up to 99% of system components can be recycled. (Sumitomo Electric also participates in the Green Transformation (GX) League, an initiative led by the Ministry of Economy, Trade and Industry of Japan, and has obtained wide-area certification for industrial waste treatment from Japan’s Ministry of the Environment.)

■ Track Record of Supplying the System to Hokkaido Electric Power Network
 

Emergency Demonstration Project for Large-Scale Energy Storage Systems (The Ministry of Economy, Trade and Industry of Japan) Capacity: 15 MW / 60 MWh Start of Operation: December 2015 (currently in operation*1)

(For reference)
■Vanadium Redox Flow Battery Website
https://sumitomoelectric.com/products/flow-batteries

■Sumitomo Electric Group e-Magazine “id” Vol. 19　
https://sumitomoelectric.com/id/project/v19/01