ICG Partners with Ray8 Energy on 1,000 MW Battery Storage Platform in Japan
ICG Asia-Pacific Infrastructure has entered into a partnership with Ray8 Energy to scale a battery energy storage system (BESS) platform in Japan, targeting over 1,000 MW of installed capacity within five years, the firm announced January 22, 2026.
The joint venture marks ICG's entry into Japan's BESS market through a majority stake acquisition in Ray8 Energy. The partnership involves approximately JPY 50 billion (approximately USD 300 million) in equity to develop projects supporting Japan's net-zero by 2050 goals.
Infrastructure Platform Development
The platform will focus on battery energy storage system development across Japan's renewable energy infrastructure. Ray8 Energy, founded by Tomohide Den, operates across the BESS lifecycle including site selection, permitting, financing through project special purpose companies, and operations with third-party partners.
The partnership builds on Ray8 Energy's existing pipeline and emphasizes long-term ownership for revenue generation from capacity markets, energy arbitrage, and ancillary services. Green Tower initially backed Ray8 Energy before ICG's majority stake acquisition.
According to Devarshi Das, Head of ICG APAC Infrastructure, the partnership positions the firm to capitalize on Ray8's experienced team and project pipeline for growth in Japan's expanding energy storage market.
Investment Strategy
The equity commitment of approximately JPY 50 billion represents ICG's fourth regional renewables platform since 2023, following investments in Voltaiyo, Revent Energy, and Ampin Energy Transition. The firm's Asia-Pacific Infrastructure equity strategy targets diversified energy transition assets in Japan, South Korea, and India.
The investment aligns with Japan's policy-driven expansion of battery energy storage to integrate variable renewable energy sources, ensure grid stability, and address power supply-demand dynamics. The country's pursuit of net-zero emissions by 2050 has accelerated demand for battery energy storage capacity for ancillary services and renewable support.
Market Context
Japan's BESS market is experiencing growth due to renewable energy mandates and grid infrastructure needs. Ray8 Energy's local networks for project origination and execution position the platform to compete in a market seeing increased developer activity and institutional capital deployment.
The partnership represents ICG's strategic expansion into energy storage infrastructure as a complement to its existing renewable energy investments in the Asia-Pacific region.