au Renewable Energy commissioned the 2MW/5.6MWh Oyama Power Storage Station in Tochigi Prefecture on August 15, 2025, the company announced on August 29, 2025. The asset is its first operational grid-scale battery storage facility.
The company’s CEO Suzuki Goro said au Renewable Energy will use the expertise acquired through the operation of the asset to implement, among other things, schemes supplying solar power generated during the day to meet the nighttime demand of its parent KDDI’s facilities.
Oyama Power Storage Station, first announced in July 2024, was built on a 324m2 plot of land on the site of KDDI Oyama Network Center in Oyama City. It uses GS Yuasa battery systems. au Energy Holdings and J-POWER joint venture Eneres has been selected as the asset’s aggregator.
TEPCO Holdings handled engineering, procurement, and construction (EPC). According to the statement, a Kandenko representative also attended the completion ceremony, suggesting the construction company contributed considerably to on-site work. The project received a 343 million yen subsidy under the Tokyo Metropolitan Government’s scheme for the promotion of grid-scale BESS.
au Renewable Energy is currently also developing a 28MW/90MWh extra high-voltage project in Mie Prefecture, which it plans to commission in April 2027.
