Sungrow Launches 'PowerStack 255CS' at Global Renewable Energy Summit 2025

The PowerStack 255CS represents a significant advancement in energy storage technology, utilizing 314Ah battery cells to deliver a capacity of 257kWh for a 2-hour system or 514kWh for a 4-hour system within a single container. Based on Sungrow’s well-regarded AC Block design, the system offers over 90 percent round-trip efficiency and is engineered for a 20-year operational lifespan. It also integrates advanced liquid-cooling and AI-controlled heat balance technologies that monitor cell temperature and operational data to optimize cooling power, reducing auxiliary energy consumption by 33 percent and improving both performance and cost-efficiency.

In terms of safety, the PowerStack 255CS meets rigorous global standards such as UL9540 and NFPA855/69/68/14. It features a comprehensive protection system that includes cell anomaly detection, multi-level overcurrent protection, early fire detection, and multiple fire suppression methods. The design incorporates cabinet, rack, and pack-level fuse protection, ensuring strong fire prevention and operational reliability.

Designed for flexibility and ease of use, the system comes fully integrated with an Energy Management System (EMS), Power Conversion System (PCS), and Battery Management System (BMS), simplifying installation and reducing onsite complexity. It supports various layout configurations, is pre-installed and pre-commissioned for quick grid connection, and can be scaled in parallel for up to 25 units, covering energy storage needs from 257kWh to 6.4MWh.

Sungrow also optimizes the PowerStack 255CS for diverse energy applications. In standalone energy storage, it offers a 100ms response time and supports frequent frequency regulation bids to maximize revenue while utilizing advanced grid-forming technology for enhanced stability. In PV + storage integration, it supports both AC and DC coupling to maximize solar power usage.

For EV charging scenarios, the system enables intelligent coordination between storage and chargers, reducing the need for transformer upgrades. In microgrid environments, the built-in PCS with a three-phase 400V AC output supports single-phase unbalanced loads and automatic switching between PV, storage, and diesel generators, ensuring uninterrupted power for critical systems.