Grid storage battery facility “NNR Shizen Energy Battery Hub Umi” holds opening ceremony

- Accelerating the storage battery business for grid stabilization -

2024.06.11[Press Release]
Grid storage battery facility “NNR Shizen Energy Battery Hub Umi” holds opening ceremony

NNR Shizen Energy G.K. (Nishitetsu Shizen Energy), a joint venture between Nishi-Nippon Railroad Co., Ltd. (Nishitetsu) and Shizen Energy Inc.(Shizen Energy), held an opening ceremony on June 10th at the site of the grid storage battery facility*1 “NNR Shizen Energy Battery Hub Umi”, which will begin commercial operation this month. 

As the deployment of renewable energy expands and becomes a mainstream power source, the Kyushu region in particular, which has many solar power plants, faces the problem of curtailment due to the amount of power generated during the day exceeding the amount of demand, and it is important to secure balancing capacity to maintain the balance between supply and demand. Nishitetsu Shizen Energy announced its entry into the grid-side storage battery business in July 2023*2 and is currently proceeding with installations. The company has now commenced operation of this storage battery facility as its first project.

Shizen Energy Group’s role in this battery storage facility is as follows: Shizen Energy is responsible for the property management, and Shizen Connect Inc. (Shizen Connect) is responsible for the control and operation of the storage batteries using its own energy management system. Shizen Connect performs a series of operations, such as market price forecasting, formulation of charge and discharge plans, and remote control, to generate revenue through trading in each electricity market, such as JEPX, balancing market, and capacity market, as well as balancing group*3 operations and retail supply of electricity for charging.

The grid storage batteries installed at this facility consist of lithium-ion batteries with an output of 1.92 MW and a storage capacity of 4,659 MWh. The company will contribute to stable electricity supply by trading the generated balancing capacity in various electricity markets, including the balancing market and the capacity market. 

To “take action for the blue planet,” the Shizen Energy Group will accelerate its renewable energy generation business that coexists with local communities, its energy storage business for grid stabilization, and its digital business for efficient use of energy equipment. Together with partners, Shizen Energy Group will flexibly respond to various needs, such as decarbonization and strengthening energy resilience, and aim to achieve a 100% renewable energy world as soon as possible.

*1 grid storage battery facility: a facility that independently connects storage batteries to the grid 
*2 Nishitetsu and Shizen Energy enter grid storage battery business (press release July 19, 2023)
*3 balancing group: a group of operators that performs the settlement of imbalance (difference between planned and actual results). There are “demand balancing groups” consisting of electricity retailers and “generation balancing groups” consisting of electricity generators


Overview of grid storage battery facility


NNR Shizen Energy Battery Hub Umi


2-17 Wakakusa, Umi-machi, Kasuya-gun, Fukuoka Prefecture (inside the Hayami parking lot of Nishitetsu)

Facility size

Output: 1.92 MW / Storage capacity: 4.659 MWh
Storage capacity is equivalent to the daily usage of approximately 400 households 

Storage battery 

Bluestorage (Leased from IBeeT Corporation)

Energy Management System 

“Shizen Connect” (Provided by Shizen Connect Inc.)


NEC Networks & System Integration Corporation

Business operator 

NNR Shizen Energy G.K.

Start of commercial operation 

June, 2024


Photo of NNR Shizen Energy Battery Hub Umi

About NNR Shizen Energy G.K.
Established in April 2022 as a joint venture between Nishitetsu and Shizen Energy. With the vision of “contributing to the decarbonization of Kyushu,” the company is engaged in the corporate PPA business, which supplies renewable energy power to the Nishitetsu Group and local companies and municipalities, and energy management business using storage batteries.

 ・Headquarters: 3-5-7, Hakata Ekimae, Hakata-ku, Fukuoka City, Fukuoka Prefecture
 ・Representative: Yasuhiro Hayashida

About Nishi-Nippon Railroad Co., Ltd.
This year marks the 116th anniversary of the founding of our predecessor company, Kyushu Electric Railway Company, in 1908.
The Nishitetsu Group, under the corporate message of “Connecting your dreams,” is engaged in a wide variety of businesses that support the daily lives of local residents. Our automobile transportation division, one of the largest in Japan, and our railroad division, which has two lines, the Tenjin-Omuta Line and the Kaizuka Line, transport approximately 2.02 million passengers per day. In addition, our divisions including international logistics, urban development, and real estate also continue to grow steadily.

 ・Headquarters:3-5-7 Hakataekimae, Hakata Ward, Fukuoka City
 ・President & CEO:Koichi Hayashida

About Shizen Energy Inc.

Founded in June, 2011. With the company purpose of “We take action for the blue planet,” the company’s business includes development, financing, and asset management of renewable energy power plants using solar power, wind power, small-scale hydroelectric power, and biomass. Since 2016, the company has also been focusing on its international operations, expanding its development and power generation projects in areas such as Southeast Asia and Brazil. In 2019, the company also entered the energy tech business, offering micro-grid and VPP construction, smart charging and discharging services for EVs, and other services through its self-developed EMS (energy management system).

 ・Headquarters: Fukuoka Ohori Bldg. 1-1-6 Arato, Chuo Ward, Fukuoka City, Fukuoka
 ・Representative Directors: Ken Isono, Kenji Kawado, Masaya Hasegawa

About Shizen Connect Inc.
Established in October 2023 through a spin-off from Shizen Energy Inc., Shizen Connect develops and provides an aggregation energy management system that collectively controls energy resources such as renewable energy power generation equipment, storage batteries, EVs, and EcoCutes. It can provide individual control for residential solar power equipment, storage batteries and EV chargers, control for microgrids connecting multiple buildings with their own private transmission lines, as well as control of VPPs for large scale energy resources. Individual control and VPP control tended to be separate, but Shizen Connect provides a comprehensive service allowing energy resources to be used multi-purposefully, which also improves economic efficiency. The system can be adapted with any equipment supplier, allowing energy resources to be chosen freely without relying on a certain manufacturer.

Head Office: 2-4-7 Nihonbashi-honcho, Chuo-ku, Tokyo
Representative Director: Munekazu Matsumura
URL: (Japanese only)