Tokyo Century : to Invest in Self-Developed Extra-High Voltage Grid-Scale Battery Energy Storage Projects (Four Domestic Locations, Total 101 MW)

NEWS RELEASE

December 12, 2025

Contributing to Power Supply Stability and a Decarbonized Society, Aiming for Early Development of Approx. 600 MW Capacity

Tokyo Century Corporation (President & CEO, Representative Director: Koji Fujiwara; Head Office: Chiyoda-ku, Tokyo; "Tokyo Century") announces that it has decided to independently invest in and develop extra-high voltage* grid-scale battery energy storage system (BESS) projects (total rated output: 101 MW) at four locations in Japan (Nasushiobara, Tochigi; Isahaya, Nagasaki; Shimabara, Nagasaki; and Taku, Saga).

This swift decision to invest in these four large-scale projects was realized by leveraging Tokyo Century's strengths: its track record and accumulated expertiseas a pioneerin the grid-scale battery business, and its ability to make rapid decisions through an independent business development structure. Moving forward, we will continue to emphasize internally-led development to enhance the speed of business formation and ensure the accumulation of operational expertise, thereby further accelerating the widespread adoption of grid-scale storage batteries.

In recent years, as the introduction of renewable energy expands, the importance of grid-scale storage batteries has increased as a power adjustment system to absorb output fluctuations and stabilize the grid. The projects aim to address such social issues and contribute to the stable supply of electricity in each region.

As one of the growth strategies in its Medium-Term Management Plan 2027, Tokyo Century has set forth the establishment of new power plants equipped with a BESS and their operation, accelerating initiatives for both grid-scale and co-located types. Particularly in the grid-scale battery business, we plan to accumulate expertise and enhance our business execution capabilities by working on self-developed projects, centered on extra-high voltage cases. Through this approach, we aim to develop sustainable businesses that coexist with local communities and achieve the early development and start of operation of approximately 600 MW capacity.

As a frontrunner in the domestic battery storage business, Tokyo Century will continue to work on expanding the batterybusiness swiftly. Wewillalso contribute to creatinga sustainable decarbonized society throughtheexpansion of renewable energy and the stabilization of power grids.

Note: Battery storage facility substations are classified as "high voltage" or "extra-high voltage" depending on the received voltage. Generally, facilities with a contracted demand of 50 kW to less than 2,000 kW receive high voltage, while large-scale facilities with that of 2,000 kW or more receive extra-high voltage.

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Tokyo Century Corporation

Public Relations & Investor Relations Division Kengo Kawai

Inquiries: https://www.tokyocentury.co.jp/en/contact/form.php Phone: +81-3-5209-6710

Note: This translation is prepared and provided for reference only. In the event of any discrepancy between this translated document and the original Japanese document, the original document shall prevail.