TESS Group: BuddyNet Inc. and Tess Engineering Co., Ltd. Conclude Business Alliance Agreement for Energy Storage Plant Development Business

Tess Holdings Co., Ltd. (Headquarters: Yodogawa-ku, Osaka; President: Kazuki Yamamoto; hereinafter "the Company") announces that its consolidated subsidiary, Tess Engineering Co., Ltd. (Headquarters: Yodogawa-ku, Osaka; President: Toshihiro Takasaki; hereinafter "Tess Engineering"), has concluded a business alliance agreement (hereinafter "the Business Alliance Agreement") with BuddyNet Inc. (Headquarters: Chuo-ku, Tokyo; President: Seiji Tsutsumi; hereinafter "BuddyNet") on April 10, 2026. The purpose of this agreement is to establish a cooperative and construction framework for project origination in the energy storage plant development business.

Background of the Business Alliance Agreement In the 7th Strategic Energy Plan approved by the Cabinet in February 2025, a goal was set to increase the share of renewable energy in the domestic power mix from approximately 40% to 50% by 2040, indicating further expected growth in renewable energy adoption. Under these circumstances, from the perspectives of effective utilization of renewable energy and stabilization of the power grid, the importance of storage batteries capable of flexible charging and discharging in response to renewable energy output fluctuations is increasing.

Given this background, the Company Group, in its mid-term management plan "TX2030"*, has designated storage system-related businesses—such as the development of grid-scale energy storage plants and the transition of solar power plants using the FIT system to FIP with co-located batteries—as one of its core business areas, aiming for a cumulative installed capacity of 850MW or more by 2030. To further strengthen the framework from project origination to construction for future business expansion, we concluded this Business Alliance Agreement with BuddyNet.

BuddyNet, a consolidated subsidiary of AKIBA Holdings Co., Ltd. (TSE Standard: 6840), develops social infrastructure construction businesses using its proprietary method "Telecommunications Construction Tech®", which fully utilizes ICT towards the realization of a smart society where all things are connected.

The company's greatest feature is its "end-to-end" system, based on a nationwide construction and maintenance framework, allowing it to complete everything from electrical facility construction to civil engineering works like land preparation and foundation work within a single company. It boasts a rich track record of construction in highly difficult renewable energy facilities, such as grid-scale batteries and large-scale solar facilities. By integrating its extensive track record in the renewable energy and civil engineering fields built over many years with advanced telecommunications construction know-how, it provides high-quality total solutions nationwide, from the design and construction of grid-scale batteries to post-operation maintenance.

Overview of the Business Alliance Agreement (1) Purpose of the Business Alliance Agreement Sharing a common vision of realizing a decarbonized society and strengthening regional resilience through the popularization of next-generation energy infrastructure, BuddyNet and Tess Engineering aim for mutual further development and corporate value enhancement. Furthermore, to realize these goals, both companies will utilize their respective areas of expertise, management resources, and know-how to cooperate on introducing customers and projects related to the battery business, and ordering construction work and related equipment.

(2) Content of the Business Alliance Agreement - Mutual cooperation in developing new projects for energy storage plants - Placing orders for construction work or equipment such as storage batteries - Assistance with site surveys, design, and sales activities related to the battery business - Introduction of battery business opportunities - Other matters agreed upon by both companies

Future Outlook By combining the customer network, business development capabilities, and engineering strength possessed by the Company Group with the nationwide construction framework, construction know-how, and on-site responsiveness possessed by BuddyNet, the framework from project origination to construction in the battery business will be strength...