Eku Energy Awarded Long-term Decarbonization Power Source Auction for Eshi Battery Energy Storage System
Media Release
To Build one of Japan’s largest battery energy storage systems with 150 MW / 600 MWh capacity in Eshi, Kasaoka City, Okayama Prefecture
Eku Energy Japan Ltd. (Headquarters: Minato-ku, Tokyo; Representative Director: Kentaro Ono; hereinafter "Eku Energy Japan"), the Japanese subsidiary of Eku Energy, a global battery storage business, today announced that it has been awarded the Long-Term Decarbonization power source Auction (LTDA) from the Organization for Cross-regional Coordination of Transmission Operators (OCCTO) for Eshi BESS, a 150 MW / 600 MWh stand-alone Battery Energy Storage System (BESS). The LTDA offers long-term contracts with fixed capacity payments, providing predictable revenue.
Eshi BESS is Eku Energy’s second project in Japan following the 30MW / 120MWh Hirohara BESS in Miyazaki Prefecture. Eshi BESS is located in Eshi, Kasaoka City, Okayama Prefecture and at 150 MW/ 600 MWh will be one of the largest BESS in Japan. Eshi BESS is expected to be operational no later than 2030. The BESS can store electricity equivalent to the power consumption of approximately 337,000 households (about 1/3 of the total number of households in Okayama Prefecture) for four hours. When it is operational, the BESS will balance supply and demand, reduce energy price volatility and contribute to the stability of the national electricity grid.
According to a survey by the Ministry of Economy, Trade and Industry the national power demand is expected to increase by about 6% to 852.4 billion kWh in 2034 in response to the expanding need for digital services such as AI. With the required growth for renewable energy capacity to come online, the need for BESS will only increase.
LTDA represents an important milestone not only for Eku Energy’s Eshi BESS but also for Japan’s goal of achieving net zero greenhouse gas emissions by 2050 with LTDA encouraging new investment to accelerate Japan’s energy transition. As the successful bidder, Eku Energy will receive payment from OCCTO towards the initial cost of constructing the BESS and running costs for the multi-year power supply.
Daniel Burrows, CEO, Eku Energy, said:
Securing the LTDA for our Eshi BESS adds further high-quality long term contracted revenue to our Japan and global portfolio with our first LTDA project in Japan diversifying our revenue mix. We are particularly proud of Eshi BESS being the latest revenue contract that is consistent with our mission to accelerate the energy transition by delivering safe, secure and reliable energy storage solutions that provide cost-effective clean energy.
Kentaro Ono, Managing Director, Eku Energy Japan, said:
Eshi BESS is another project that demonstrates our approach built on partnerships and collaboration with local stakeholders and communities. This project is one of the largest BESS announced in Japan and this award shows our extensive expertise covering project development, investment, construction and operation engineering across the entire BESS lifecycle.
For more information about Eshi BESS, please visit www.ekuenergy.com/eshi.
Eku Energy's success in this tender aligns with its broader strategy to develop and manage a diversified portfolio of energy storage assets globally. The company continues to collaborate with governments, developers, and local communities to deliver projects that facilitate the energy transition and provide long-term value. In February 2025, Eku Energy was awarded a Long Duration Storage Long-Term Energy Service Agreement (LDS LTESA) in Australia from AEMO Services, for a 100 MW / 800 MWh BESS in Yoogali, within the Griffith Local Government Area (LGA) of New South Wales. Eku Energy focuses exclusively on BESS with 7 projects in construction and operations globally.