PowerX Unveils "Mega Power 4000" Series, High-Capacity Battery Energy Storage Systems for Utility-Scale Projects

TOKYO, JAPAN --- PowerX, Inc. (Head Office: Tamano City, Okayama Prefecture; Director, President and CEO: Masahiro Ito; Securities Code: 485A) today unveiled the "Mega Power 4000" series, a new lineup of high-capacity battery energy storage systems (BESS) in 20-foot containers, designed to meet the growing scale of grid battery farms and to compete in global markets. The series comprises two models with storage capacities of 4.6 MWh and 4.2 MWh, depending on the battery cells used, with mass production scheduled to begin in May 2027.

As renewable energy adoption accelerates worldwide, utility-scale battery energy storage projects continue to grow in scale. In Japan, the average size of successful BESS bids in the Long-Term Decarbonization Power Source Auction*1 expanded from 36 MW in FY 2023 to 66 MW in FY 2025, and the share of large projects of 75 MW or more rose from 3% to 37%*2. In such large projects, the number of BESS units and the scale of on-site construction significantly affect overall project costs, driving demand for greater capacity per container.

To meet these customer needs, PowerX developed the "Mega Power 4000" series, which features a high density design incorporating liquid-cooled lithium iron phosphate (LFP) batteries in a 20-foot container. PowerX positions the series as its global strategic model and has begun making proposals to customers in Japan and overseas, aiming for full-scale expansion into markets such as Australia and Southeast Asia.

PowerX will offer a standard package combining the new BESS with "Grid Connector for BESS," a grid interconnection system also announced today that integrates power conditioning systems (PCS), transformers, and high-voltage switchgear, as its core solution for large-scale battery power plants in Japan and overseas. By optimizing BESS and grid interconnection equipment as a fully integrated solution, PowerX will reduce construction costs and shorten the time to commercial operation. Through these efforts, the company aims to differentiate its storage solutions and strengthen its competitiveness.

Key features of the "Mega Power 4000" series are as follows.

Industry-leading Energy Density through high-density design and double-stack installation

Each unit offers a storage capacity of up to 4,680 kWh, approximately 1.7 times the capacity of PowerX's existing product of the same footprint. For a battery farm of comparable scale, this reduces the number of battery containers required by roughly 40%, reducing construction costs associated with foundations, wiring, installation, and on-site commissioning---and shortening construction timelines.
In addition, this is the first PowerX product designed to support double-stack installation of battery containers. When double-stacked, up to 9,360 kWh can be installed per 20-foot container footprint (approximately 14.8 m²), approximately 3.4 times the storage capacity of the company's existing product, enabling more effective use of land.

Support for multiple battery cell suppliers

The series adopts a universal battery container design compatible with multiple battery cell suppliers from different manufacturers and countries of origin. This enhances supply stability and enables cost reduction while responding flexibly to changes in the procurement environment.

Designed for transport in Japan and overseas

The series uses standard-sized 20-foot containers conforming to international standards (ISO), balancing transportability and high capacity for delivery both in Japan and overseas. In Japan, transport weight is kept at 32 tonnes or less, allowing delivery to installation sites via existing road infrastructure. For overseas markets, the series is planned to comply with "UN 3536 (lithium batteries installed in cargo transport unit)" under dangerous goods transport regulations, which is expected to enable marine shipment with the container as a single integrated unit.

Resilience to natural disasters and noise, and cybersecurity

The series incorporates safety features designed for operation in Japan, a country prone to natural disasters. For earthquakes, an inertial measurement unit (IMU) detects abnormal motion during seismic events and initiates safety controls such as opening the contactors. For typhoons and other strong winds, the enclosure is designed to provide secure anchoring to foundations and wind resistance. To address noise, a growing concern in battery farm operations, optional active noise cancellation is also available to help reduce operational noise.

In addition, for the cybersecurity required of power infrastructure, the series is planned to conform to "JC-STAR"*3, a security conformity assessment and labeling scheme for IoT products under which PowerX's existing products have already obtained conformance labels.

For product details, please see the product presentation and the website.
Video URL:https://www.youtube.com/live/UEW-B06y8Gc
Website:https://power-x.jp/megapower/4000series

^{*1 A bidding scheme conducted by the Organization for Cross-regional Coordination of Transmission Operators (OCCTO) to support new investment in decarbonized power sources.
*2 Compiled by PowerX based on the contract results of the Long-Term Decarbonization Power Source Auction.
*3 A security requirements conformity assessment and labeling scheme operated by the Information-technology Promotion Agency (IPA).}

^{This document has been translated from the Japanese original for reference purposes only. In the event of any discrepancy between this translated document and the Japanese original, the original shall prevail.}