Mitsubishi HC Capital Energy and RS Asset Advisors will proceed with the construction of three high-voltage grid-scale battery storage projects totaling about 6MW/24MWh in Gunma and Tochigi prefectures, the companies announced on July 9, 2026.
According to the statement, each of the three Tokyo TSO area projects will be approximately 2MW/8MWh. Construction is scheduled to begin in October and November 2026. Two of the assets are expected to be commissioned in January 2027, with the third following in February 2027.
The projects are the first disclosed since the two companies partnered in 2024 to cooperate on grid-scale battery storage. Under the tie-up, Mitsubishi HC Capital Energy was expected to invest in the assets and lead equipment and aggregator selection. RS Asset Advisors was expected to handle negotiations related to specific projects and asset management.
Separately, Mitsubishi HC Capital Energy holds a 65% stake in the 25MW/50MWh Kamiosatsu Hikari Power Storage Station, which targets a January 2027 COD. Its parent Mitsubishi HC Capital was awarded approximately 3 billion yen for a project in Shizuoka Prefecture jointly with Kowabo under METI’s FY2025 grid-scale battery storage subsidy scheme.
RS Asset Advisors previously also partnered on grid-scale battery storage development with Maeda Corporation and Fuyo General Lease, and formed an asset management joint venture with Sumitomo Mitsui Trust Bank. It was also selected as the developer and asset manager for a 40MWh portfolio of five projects held jointly by Hulic, Fuyo General Lease, and Itochu.
