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NEDO Demonstration Project Using Redox Flow Battery in the U.S. Receives the ISGAN Award 2024
- Awarded at CEM15 as a Best Practice that Contributes to Ensuring the Grid Resilience -

October 11, 2024
New Energy and Industrial Technology Development Organization (NEDO)

Translation of Japanese NEDO news release posted on October 10, 2024

NEDO and Sumitomo Electric Industries, Ltd. (Sumitomo Electric) conducted a microgrid demonstration project on an actual power distribution grid using redox flow battery (RFB), in California from 2015 to 2021, in collaboration with the California government and San Diego Gas & Electric Company (SDG&E), which is a major investor-owned utility. Sumitomo Electric, an operator of the RFB system has received the ISGAN Award 2024, in recognition of its achievements in this demonstration project.
The Annual ISGAN Awards are recognized as outstanding smart grid initiatives from around the world, and this year's 10th award was held under the theme of "Flexibility for Grid Resilience." Given the recent changes in the international resource situation and the increasing frequency and severity of natural disasters, the need to improve the resilience of power infrastructure has now become much greater than ever, not only in Japan but also in other countries. This demonstration project has been highly praised as one of the global best practices that can contribute to ensuring the grid resilience. The awards ceremony was held on October 2nd at the 15th Clean Energy Ministerial (CEM15) in Brazil, and the project was widely promoted around the world as an innovative and effective model case in smart grid development.

RFB system installed in California, USA Picture
Figure 1 RFB system installed in California, USA

1. Overview

From September 2015 to December 2021, NEDO and Sumitomo Electric conducted a microgrid demonstration project*1 on an actual power distribution grid in San Diego, California, in cooperation with the California Governor's Office of Business and Economic Development (GO-Biz) and SDG&E, a major investor-owned utility in the state. This demonstration tested RFBs*2, which are long-life stationary storage batteries suitable for larger scale use. And Sumitomo Electric built and operated a system using RFBs in one of SDG&E's substations. The system with RFB has the advantages of few operational constraints and a low degradation rate. And it has been demonstrated that a microgrid operation can supply power to areas experiencing or planning blackouts, and act as independent power sources in emergencies such as disasters or planned blackouts, while contributing to generation of revenue through electricity market transactions during normal times.
The ISGAN Awards are recognized as outstanding smart grid initiatives implemented around the world, and this year marked its 10th anniversary with the theme of "Flexibility for Grid Resilience." The International Smart Grid Action Network (ISGAN)*3 is a technology collaboration program of the International Energy Agency (IEA) that promotes the development and dissemination of smart grid-related technologies on a global scale and organizes the ISGAN Awards in collaboration with the Global Smart Energy Federation (GSEF)*4. The fact that this demonstration project has been recognized in a framework that includes governments, research institutes, and industry from 26 countries and regions indicates that its efforts have been highly evaluated internationally.
In recognition of the achievements of this demonstration project, Sumitomo Electric was awarded an Honorable Mention*5 at the ISGAN Award 2024 from a large number of applicants. This is the third time a Japanese company has received the ISGAN Award. Given the recent changes in the international resource situation and the increasing frequency and severity of natural disasters, the need to improve the resilience of power infrastructure has now become much greater than ever, not only in Japan but also in other countries. This demonstration project using a RFB system has been highly evaluated as one of the global best practices that can contribute to ensuring the grid resilience and should be shared with the world.

2. Overview of the Demonstration Results

In the demonstration project, the RFB system was used for load adjustment and voltage control in an actual power distribution grid and was shown to contribute to improving profits in the energy market, where electricity is traded and in the ancillary services market* 6* 7. Furthermore, as microgrid operations are gaining attention as one of the measures to grapple with natural disasters and planned and rotating blackouts that were becoming a problem in California, this project additionally demonstrated the capabilities*8 such as;
a) black start, starting the RFBs without an auxiliary power source during a blackout
b) seamless transition to islanded mode, an uninterrupted transition from a grid-connected state to an independent operating state so that consumers do not notice a blackout.
It was confirmed through the demonstration project that the system with RFBs is quite suitable for economically supplying power to areas experiencing power outages, as a power source to operate a microgrid during emergencies, and for power trading during normal times.

3. Award ceremony and presentation of results

The ISGAN Award 2024 ceremony was held on October 2nd at CEM15 in Brazil, and the project was widely promoted around the world as an innovative and effective model case in smart grid development.
The results of this demonstration can also be applied to solve power quality problems in remote islands and other areas where traditional power sources such as diesel generators are being replaced by renewable energy sources such as solar and wind power. It is expected that the application of these results to remote islands and regional microgrids in Japan will contribute to a stable supply of power and the further spread of renewable energy.

  • The award ceremony Picture
    Figure 2 The award ceremony
    (Third from the left: Mr. KAWABATA Shigeru, President & CEO of Sumitomo Electric USA, Inc., who was on stage as an award honoree.
    Second from the right: Mr. KIHARA Shinichi, Director-General for Energy and Environmental Policy, Agency for Natural Resources and Energy, who served as a presenter on behalf of ISGAN member countries and Japan)

[Notes]

  • *1 Demonstration Project
    Project title: International Demonstration Project to Prove Japanese Technology for Improved Energy Consumption Efficiency/Demonstration Project Testing Storage Battery Operation for Both Electricity Transmission and Distribution in California, USA
    Project period: FY2015 to FY2021
    Project overview: International DemonstrationProject on Japan's Technologies for Decarbonization and Energy Transition
  • *2 RFB
    The RFB system consists of cells for the battery reaction, tanks for storing active materials, pumps, and pipes for circulating electrolyte and conducts charging and discharging using the oxidation-reduction (redox) reaction of active materials such as vanadium. It is a long-life product which does rarely see degradation in electrodes and electrolytes and is a fireproof battery with robust safety as the electrolytes are non-combustible and it can be used at an ambient temperature. The SOC (state of charge) is measurable. And RFB system has the unique feature that power output (kW) and power capacity (kWh) can be designed independently by adjusting the amount of electrolyte.
    The capacity of the RF battery provided for this demonstration is 2MW/8MWh.
  • *3 International Smart Grid Action Network (ISGAN)
    It is an international network of 26 member countries and the European Commission that serves as a technical cooperation program of the International Energy Agency (IEA) with the aim of promoting the development and dissemination of smart grid-related technologies on a global scale.
    Japan is represented by NEDO and the Ministry of Economy, Trade and Industry.
  • *4 Global Smart Energy Federation (GSEF)
    It is an international organization that brings together private companies and academic institutions from around the world who are working to build smart and clean electricity systems. It supports collaboration between related governments and non-governmental organizations and shares relevant technologies and policies from each country.
  • *5 Sumitomo Electric was awarded an Honorable Mention
    (Reference) Sumitomo Electric release (October 11,2024)"Sumitomo Electric Receives the ISGAN Award 2024 for NEDO Demonstration Project Using Redox Flow Battery in the U.S"
  • *6 Ancillary services market
    This is a market operated for the purpose of procuring the reserve and adjustment power necessary for a stable power supply. All electricity supply and demand in California is handled through the California Independent System Operator (CAISO) market, and the ancillary services market is also operated by CAISO.
  • *7 The RFB system was shown to contribute to improving profits in the energy market, where electricity is traded and in the ancillary services market.
    (Reference) NEDO News Release (January 22, 2021)"NEDO Extends Redox Flow Battery System Project to Conduct an Additional Demonstration of a Microgrid as a Solution to Power Outages in California"
  • *8 This project additionally demonstrated the capabilities such as a) black start and b) seamless transition to islanded mode.
    (Reference) NEDO news release (April 6, 2022)"First time in the U.S. and Japan to Successfully Build and Operate Microgrid withBattery Storage on Actual Power Distribution Network. "

4. For more information, please contact:

Grid Interconnection Unit, Renewable Energy Department, NEDO TEL: +81-44-520-5270

International Projects Department, NEDO TEL: +81-44-520-5190