erex Co., Ltd.

erex Decides to Invest in its First “BESS Integrated with Solar Power” Project

erex Co., Ltd. (Headquarters: Chuo-Ward, Tokyo; Representative Director & President: Hitoshi Honna; hereinafter referred to as “the Company”) is pleased to announce that it has decided to make a new investment in BESS integrated with renewable energy (hereinafter referred to as “the Project”) as part of its aggregation business, which contributes to the expansion of renewable energy adoption and the stabilization of electric power supply and demand. Operations are scheduled to start in the first half of 2027.

The Project marks the Company’s first investment in BESS integrated with renewable energy.

1. Background and Objective of the Project
In Japan, the 7th Basic Energy Plan was approved by the Cabinet in February 2025.This plan projects that the electric power generation is expected to increase from 853.8 billion kWh with renewable energy ratio of 26.5% in fiscal year 2024 (preliminary figures) to 1,100-1,200 billion kWh with renewable energy ratio of around 40-50% by fiscal year 2040. As renewable energy sources such as solar and wind power become the mainstay of the energy mix, adjusting the balance of electric power supply and demand will be critical to ensuring a stable power supply. Furthermore, there is a growing need for renewable energy procurement, particularly among large-scale customers. Against this backdrop, the aggregation business is expected to become indispensable, and the market is anticipated to expand.

Illustration of Electric Power Supply/Demand Adjustments

As announced on June 9, 2025, in “The Company’s Aggregation Business Strategy”, the Company is expanding its aggregation business through grid-scale BESS, BESS integrated with renewable energy, development of renewable energy sources, and support for the utilization of in-house renewable energy.

In the Project, the Company will install BESS at the solar power plant (hereinafter referred to as “the Power Plant”) owned by Munakata Asty Solar Power Co., Ltd. (Headquarters: Fukuoka City, Fukuoka Prefecture; Representative Director & President: Toshiyuki Kamakura), a wholly-owned subsidiary of Nishinippon Plant Engineering and Construction Co., Ltd. (Headquarters: Fukuoka City, Fukuoka Prefecture; Representative Director & President: Naoyuki Toyoshima). The Company will purchase electric power from the Power Plant and seek to generate earnings through market transactions. Through this initiative, the Company will contribute to grid stabilization, widespread adoption of renewable energy, and realization of de-carbonized society.

This investment decision is based on the strategy outlined in the announcement titled “The Role and Growth Opportunities of “BESS Integrated with Renewable Energy” within erex Group’s Aggregation Strategy”, released on March 30, 2026.

2. Project Overview
The Power Plant will transition from the current FIT system to the FIP system, and the Company will install BESS on the Power Plant’s premise. As a BESS operator and aggregator, the Company will purchase the renewable energy generated at the Power Plant at a price equivalent to the FIT price. Leveraging the extensive expertise in supply/demand forecasting and advanced control technology, the Company will generate profit by charging during hours when electric power market prices are low and discharging during hours when prices are high. Furthermore, the Company will promote the effective utilization of renewable energy by avoiding output control – which has become increasingly common in recent years due to factors such as increase in renewable energy generation and weather conditions.

The Project will explore ways to enhance the value of this BESS station, looking beyond arbitrage trading through the charging and discharging of BESS to include its use as frequency adjustment capabilities and the local generation and local consumption of renewable energy.

Project Overview

Overview of the BESS

Overview of the EPC Contractor and O&M Company

Overview of the Solar Power Generation Business Company

The Company’s Aggregation Business
See “1st Half of FY March 2026 Supplementary Materials for Financial Results (Announced on November 11, 2025)

[Press Releases Regarding the Company’s Aggregation Business to Date]
■September 4, 2025
Investment Decision for the First Grid-Scale BESS Project, Development of a 2MW Output / 8MWh Scale BESS Station in Kushima City, Miyazaki Prefecture
20250904_Utility-Scale-Battery-Unit-No.-1-Press-Release.pdf
■November 4, 2025
Announcement Regarding an Agreement with SAMSUNG C&T JAPAN on Joint Development of Grid-Scale BESS Business and Others in Japan
https://www.erex.co.jp/en/news/information/730/
■March 30, 2026
The Role and Growth Opportunities of “BESS Integrated with Renewable Energy” within erex Group’s Aggregation Strategy
https://www.erex.co.jp/en/news/pressrelease/747/

■ Contact
erex Co., Ltd. / IR&PR Department
TEL：+81-3-3243-1167
E-mail：ir.info@erex.co.jp

Note:
This document is an English translation of the original Japanese language document and has been prepared solely for reference purposes. No warranties or assurances are given regarding the accuracy or completeness of this English translation. In the event of any discrepancy between this English translation and the original Japanese language document, the original Japanese language document shall prevail in all respects.