Overview
Smart grids are moving from “equipment supply” to “world-class advanced manufacturing clusters.” On October 16, Nanjing released its 15th Five-Year smart-grid plan, targeting industry scale above 1 trillion yuan by 2030 with a “one valley, three zones, two poles” layout. Nanjing now hosts about 1,900 smart-grid firms, 950 above-scale, with Jiangning district exceeding 250 billion yuan in 2025.
Technology paradigm is breaking through in parallel. On October 19, China Southern Power Grid’s Guangdong unit put into operation a ±10 kV medium-voltage DC solid-state transformer (SST) in Hengqin, Zhuhai, independently developed by Zhuhai Power Supply Bureau. The 1 MW unit uses SiC chips, reaches 98.5% peak efficiency, cuts footprint and cost over 30%, isolates faults within 0.1 ms, and builds a DC “common bus” letting PV, storage, charging and data centers connect locally and share dispatch.
Both signal the same direction: rebuilding the grid with digital intelligence and new equipment to support source-grid-load-storage coordination and “multi-station integration.”
Background & Interpretation
1. Industry and Policy Context
Under dual carbon, the new power system accelerates and the grid shifts from “passive transmission” to “active regulation.” Traditional AC transformers only step voltage and transmit passively, struggling to interface DC distributed resources (PV, storage, chargers). As DC devices surge, SSTs replace electromagnetic transformation with power electronics—the key to breaking the bottleneck. Nanjing pursues a trillion-cluster path via agglomeration, digital enablement and collective going-global.
2. Core Drivers and Underlying Mechanism
The SST logic is “rebuild the transformer with semiconductors.” Silicon carbide (a third-gen semiconductor) is high-voltage/temperature tolerant, faster-switching, lower-loss; multi-chip current sharing minimizes loss. Improved circuitry halves modules, slashes size/cost, and enables millisecond fault isolation, raising safety. It directly links PV/storage/charging/data-center DC sides into a “common bus,” cutting multi-stage AC/DC conversion—the energy base for “six-network synergy.”
3. Market Structure and Industry Chain Impact
Nanjing’s “one valley, three zones, two poles” covers the full source-grid-load-storage chain: Jiangning smart-grid valley (relay protection, dispatch automation leading), Lishui (charging, storage, hydrogen), Liuhe (wind, storage, battery recycling). NARI Group is the core, with Guodian Nanjing, KYland etc. The Hengqin demo validates SiC devices and DC distribution engineering feasibility, benefiting power semiconductors, DC equipment and EMS vendors.
Implications & Outlook
Near term, SSTs will be scaled across Guangdong’s grid, driving SiC-device and DC-distribution investment. Medium term, Nanjing’s trillion plan boosts high-end equipment, source-grid verification and grid automation; Jiangning targets 350 billion yuan by 2030. Long term, the smart grid becomes the “operating system” of the new power system, with source-grid-load-storage integration scaling from parks to cities.
Takeaways for Industry Participants
Equipment firms: consolidate edges in relay protection, dispatch automation and grid-stability control; accelerate SiC and DC-equipment deployment. Parks and energy players: use integrated planning to build VPPs and green parks. Investors and SOEs: capture the 15th-Five-Year smart-grid fund and collective export chances. Standards bodies: advance SST and battery-passport standards for the new power system.
This column compiles industry information and shares technical perspectives; it does not constitute investment advice.