Announcement of Certification as a Specified Wholesale Supplier (Aggregator)

■ Overview

Blue Sky Energy Co., Ltd. is pleased to announce that it has submitted a notification to the Minister of Economy, Trade and Industry as a Specified Wholesale Supplier (Aggregator)*2, as defined by the Specified Wholesale Supply Business System*1 under the Electricity Business Act, and was certified on April 1, 2026. We plan to develop 100 grid-scale storage power plants nationwide by 2029, and on March 23 of this year, we commenced commercial operation of our first storage power plant in Makinohara City, Shizuoka Prefecture. To efficiently and stably operate a group of 100 storage power plants, aggregation functions responsible for electricity market transactions, supply-demand adjustment, and grid operation are indispensable. The acquisition of this aggregator license was strategically pursued as a strengthening of the business foundation to support this large-scale development plan.

■ About Our "Multi-Aggregator Strategy"

Our company develops and operates 100 large-scale battery facilities nationwide. To maximize profits from electricity trading, three types of partners are essential: "aggregators," "battery systems," and "control systems." Instead of entrusting all of these to a single company, we adopt a policy of selecting and combining the best companies based on location and conditions. Furthermore, by not only relying on external parties but also possessing our own electricity trading decision-making functions, we achieve both flexibility and risk diversification. Through this "best-of-breed" strategy, we aim for maximum revenue and stable operation at each location.

■ Partner Selection through the "Best-of-Breed Strategy"

Our company adopts a policy of independently selecting aggregators, battery systems, and EMS for each storage power plant. The grid-scale battery storage business is a rapidly developing market, and the speed of technological innovation and cost reduction varies across different areas. By separating each element and combining the optimal ones, rather than being fixed to a specific package solution, we aim to achieve both technological superiority and cost competitiveness.

■ Precedent: Makinohara City, Shizuoka Prefecture, First Storage Power Plant

As the first step in our nationwide development of 100 locations, we commenced commercial operation of a grid-scale storage power plant in Makinohara City, Shizuoka Prefecture, on March 23, 2026. In Makinohara City, where solar power generation is thriving, we are effectively utilizing surplus regional renewable energy and contributing to the stabilization of the power grid.

■ Future Developments

By holding both the certification as a Specified Wholesale Supplier (Aggregator) and registration as a Retail Electricity Business Operator, our company has established a system to consistently provide the entire battery value chain, from "development → EPC → O&M → aggregation," within our own group.

In promoting the nationwide 100-location storage power plant development program by 2029, under the multi-aggregator strategy, we will pursue the optimal combination of aggregators, battery systems, and EMS for each site, contributing to the maximization of business profits and the stabilization of the power grid.

※1

What is the Aggregator System (Specified Wholesale Supply Business System)?

A new mechanism that bundles "distributed energy resources" and supplies them to the electricity market.

Until now, electricity supply has mainly been a one-way flow from large-scale power plants (thermal, nuclear, etc.). Under this system, aggregators use IT technology to collectively control (aggregate) small amounts of electricity from "solar power generation" and "storage batteries (including EVs)" scattered in homes and businesses.

※2

What is an Aggregator (Specified Wholesale Supplier)?

It is a "control tower that bundles small, distributed energy and supplies it smartly."

While large-scale power plants were traditionally the main players, there is a growing demand to connect "small power resources scattered throughout cities," such as household solar panels and electric vehicles, via a network to make them function like a single large power plant.

Aggregators issue instructions to these resources, such as "store electricity" and "discharge electricity," and supply power to electricity companies. They are next-generation energy business players newly positioned by the revised Electricity Business Act to realize a decarbonized society.https://www.enecho.meti.go.jp/category/electricity_and_gas/electricity_measures/009/list/aguri-list.html

■ About Blue Sky Energy

Blue Sky Energy, with the slogan of connecting natural energy to the future, is focused on making renewable energy a primary power source and initiatives to pass it on to the next generation. We primarily engage in repowering work for solar power plants that do not involve large-scale development, and EPC and development projects related to storage power plants. We have 24 locations nationwide and handle everything from land procurement to the development and construction of power plants and storage facilities, as well as management operations such as weeding, snow removal, and daily repairs. Currently, we are focusing on repowering and storage power plant development, with a track record of over 100 locations and 150MW for repowering, and planning to develop over 50 grid-scale storage power plants nationwide by 2027, as well as developing battery storage systems co-located with solar power plants.

Company Name	Blue Sky Energy Co., Ltd.
Location	Nihonbashi 3-9-1, Nihonbashi 3-chome Square 2F, Chuo-ku, Tokyo
Representative	Miki Uehara
Established	October 2012
Business Activities	Development, construction, operation, and management of solar power plants and storage power plants, etc.
Official Website	https://www.blueskyenergy.co.jp