Sumitomo reveals testing results of redox flow battery project in California

Sumitomo said that external experts collected data from the 2MW/8MWh Redox Flow Battery Demonstration Project until the end of 2021. A preliminary analysis conducted in December revealed that the battery system achieved a 99% operating rate in the final year of the project. Sumitomo believes that the battery system has the potential to retain a capacity rate of 90% or more for 20 years in the electricity market.

The experts assigned a rating of 2.6 out of three to the overall project results. Sumitomo said that the demonstration project successfully showcased the business feasibility of using storage battery technologies for electric power market bidding and the fundamental capabilities of redox flow batteries in microgrid applications. The battery operates within a microgrid, supplying power to 66 residential and commercial customers for approximately five hours.

Sumitomo and SDG&E set up a microgrid by integrating the battery into an electrical distribution network. This setup demonstrated the battery’s dual operation capability, allowing it to serve the wholesale electricity market under normal conditions and provide grid resilience during emergencies. The battery also features black start capability, enabling it to initiate and sustain service even after a complete power outage.

The project received support from Japan’s New Energy and Industrial Technology Development Organization (NEDO) and California’s GO-Biz. Development of the project commenced in 2015. Sumitomo has already deployed 37 redox flow battery systems across multiple countries, with a total capacity of 47 MW/162 MWh.