According to a September 15 report by China Southern Power Grid's official newspaper (Southern Grid News, republished on csg.cn), the first sodium-ion battery storage unit within CSG's network (per CSG's own framing) has begun operation in an urban village in Shenzhen: Shenzhen Power Supply Bureau completed grid-connection commissioning and officially commissioned the unit at the No.8 distribution transformer station area of Dunbei New Village. This marks the first application of sodium-ion battery storage in the end-of-grid management of Shenzhen's distribution network. Urban villages in Shenzhen feature dense populations and concentrated loads, where evening peaks tend to overload transformers, cause voltage drops and frequent trips; the conventional fix - transformer capacity upgrades - often faces space constraints and long construction cycles.
Technically, the unit adopts a new generation of high-safety, high-performance, long-life composite polyanionic sodium batteries with strong explosion-proof performance suited to densely populated areas. It achieves millisecond-level uninterruptible switchover when the main power fluctuates or is interrupted, with intelligent output regulation based on load changes to both prevent transformer overload and extend storage runtime. The pilot uses a dual-unit fault-tolerant configuration. Monitoring data show that the unit discharges at full power after 9 p.m., bringing transformer loading down from 93.6% into the 79.5% safe range, fully covering residential peak hours, with consecutive days of zero transformer overload. Compared with conventional capacity upgrades, the unit requires no large-scale civil works; its modular structure has a small footprint and a construction period of only 15 days.
Unit capacity, cell supplier and investment amount were not disclosed; the first-in-network claim is CSG's own framing; it remains a single-point demonstration and does not yet indicate the pace of scale-up for this scenario.