Sinexcel and Namcha Barwa have signed a market cooperation agreement to develop utility-scale BESS projects across Japan. Sinexcel will supply StellaON PCS platforms with grid-forming, ride-through and black-start functions. Namcha Barwa will manage local project development and grid connection. The partnership supports Japan’s grid flexibility, renewable integration and localized after-sales service.
PROJECT SNAPSHOT
Project: Strategic cooperation for Japan’s energy storage market
Capacity: SINEXCEL has 17 GW of installed storage capacity globally
Location: Japan, with local operations registered in Tokyo
Developer: Namcha Barwa Co., Ltd.
Technology: Utility-scale PCS and BESS solutions
Contract: Strategic cooperation agreement
Status: Partnership signed; local service and execution support in place
Power equipment manufacturer Sinexcel has entered into a market cooperation agreement with Tokyo-based clean-energy developer Namcha Barwa Co., Ltd. to develop and execute utility-scale BESS projects across Japan. The agreement covers project engineering, asset deployment, PCS supply, and after-sales support.
Under this framework, the two companies hold separate operational roles. Namcha Barwa will manage local project development and grid-connection processes at large-scale renewable and storage sites. Operating as the technology provider, Sinexcel supplies utility-scale Power Conversion Systems (PCS) alongside engineering and maintenance services. The companies are also setting up local execution teams in Japan to support on-site engineering, spare parts management, and technical training near project locations.
The deployment relies on Sinexcel’s StellaON 1250K/1575K and 1375 kW PCS platforms, which have been adapted to meet Japan’s regional grid interconnection rules and certification requirements from independent testing bodies. The system is designed to support Japan’s islanded grid topology and disaster-resilience needs, with grid-forming capabilities. The hardware includes high- and low-voltage ride-through functions, as well as black-start capabilities, to support peak shaving and reactive compensation at large renewable installations.
The system uses preconfigured medium-voltage stations for high-power-density integration. The 20-foot stations support 2.5 MW to 5 MW capacity, while the 40-foot stations support 10 MW to 12.5 MW. Full-chain reliability validation for the product shows a mean time between failures of over 300,000 hours.
The agreement builds on Sinexcel’s five-year operational history in Japan, where the firm has delivered over 50 energy storage projects, ranging from 30 kW and 500 kW units to megawatt-level utility sites. Since January 2026, Sinexcel has commissioned eight 2 MW/8 MWh utility-scale storage systems across six prefectures. The company has also completed interconnection filings with seven regional utilities and integration testing with seven Japanese energy management system vendors.
To support operations in Japan, Sinexcel’s Japanese subsidiary has completed legal registration in Tokyo, backed by local sales, pre-sales, and after-sales personnel. Globally, Sinexcel has deployed 17 GW of installed storage capacity across more than 5,000 projects in 60 markets since the company was founded in 2007, alongside an expanded portfolio of EV DC chargers and active harmonic filters.
The cooperation supports energy storage deployment in Japan by combining local project development with grid-compliant PCS technology and service operations. The partnership may also help large-scale BESS projects meet regional utility interconnection requirements and support renewable energy integration across Japan’s power network.