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Views: 244 Author: Site Editor Publish Time: 2026-03-28 Origin: Site
Project Name: Grid-connected Energy Storage Project of a Commercial Complex in Yuzhong District, Chongqing
Total Installed Capacity: 1.25MW/5MWh
Installation Location: Underground Equipment Area on B3 Floor of the Commercial Complex (renovated from idle space, no parking spaces occupied)
Commissioning Time: March 2026
Core Applications: Grid peak shaving and valley filling, backup power supply, renewable energy consumption, peak-valley price arbitrage
As a core high-density business district, Yuzhong District faces prominent challenges in energy storage deployment:
Scarcity of above-ground space: No available land for outdoor energy storage, and no room for peripheral expansion;
Strict safety thresholds: Lithium-ion batteries and other systems with thermal runaway risks are explicitly prohibited from underground installation;
Intense grid pressure: The commercial complex has a high daily peak power load, and the sharp peak load in summer severely impacts the power grid, requiring supporting energy storage to relieve pressure.
The SINJI 1.25MW/5MWh VRFB vanadium redox flow battery system has become the only compliant technical choice for underground installation due to its intrinsic safety and space-saving design.
100% non-flammable electrolyte: Water-based vanadium electrolyte contains no flammable components, with no thermal runaway risk under puncture, extrusion, overcharge or short circuit, fully complying with underground fire protection standards;
Physical separation of stack and storage tank: Energy storage and power conversion are decoupled, avoiding chain reactions even in case of leakage, and ensuring the safety of building structures and personnel;
No high-temperature or toxic emissions: Operating temperature is stable at around 30℃, with no toxic gas release, requiring no special ventilation and meeting civil air defense requirements;
Fault self-limitation: Abnormal reactions can be terminated by cutting off the circulating pump, with no risk of diffusion, perfectly adapting to the fire protection system of commercial buildings.
Split layout: Stack units (power modules) and electrolyte storage tanks (energy modules) are physically separated, flexibly fitting into corner spaces of underground equipment areas without occupying any parking spaces;
Stacked installation: Stacks are installed in multi-layer racks, and storage tanks are arranged along walls, significantly improving space utilization;
Compliant maintenance channels: A 1.2m maintenance channel is reserved, meeting fire protection standards and facilitating safe operation and maintenance.
Humidity resistance: IP54 protection rating for the whole system, anti-corrosion treatment for key components, adapting to environments with humidity over 90%;
Wide temperature range: Designed to operate at -40℃~60℃, the constant underground temperature further enhances system stability;
Low ventilation demand: Low heat dissipation design requires only basic air exchange instead of forced ventilation, reducing energy consumption;
Lightweight load-bearing: Unit area load-bearing ≤800kg/㎡, complying with underground building structure standards.
Stack unit: Total output power ≥1.25MW, adapting to grid connection requirements;
Electrolyte system: Total energy storage capacity 5MWh, using anti-corrosion atmospheric pressure storage tanks for safe operation in closed underground spaces;
PCS & BMS: High-power bidirectional converter supporting 50/60Hz for seamless grid connection; BMS monitors the entire system in real time;
Temperature control system: Independent circulating cooling, with higher energy efficiency in underground environments, maintaining stable electrolyte operating temperature.
Site survey: Laser scanning for precise dimensions and 3D modeling for equipment layout planning;
Foundation renovation: Local ground leveling, load-bearing reinforcement, and installation of leak-proof trays;
Modular installation: Step-by-step completion of stack units, electrolyte storage tanks, pipeline connection, and electrical wiring;
Overall commissioning: Unified testing of the 1.25MW/5MWh system to achieve rapid acceptance and commissioning.
Peak shaving capacity: Continuous discharge during peak hours reduces grid peak pressure and significantly saves basic electricity costs;
Backup power supply: Provides 1.25MW emergency power to ensure uninterrupted operation of core areas (supermarkets, cinemas, data rooms);
Peak-valley arbitrage: Charging at off-peak low prices and discharging at peak hours generates stable price spread income, shortening the investment payback period;
Carbon emission reduction: Substantial annual carbon reduction, helping the commercial complex achieve green, low-carbon and carbon neutrality goals.
Long maintenance-free cycle: Stack cycle life exceeds 20,000 cycles, requiring no large-scale maintenance for years, with lower O&M costs in underground environments;
Remote monitoring: Cloud-based BMS for real-time monitoring and automatic abnormal alarms, reducing on-site inspection frequency;
Safety compliance: Zero failures since commissioning, passing fire protection and civil air defense acceptance, and becoming a regional underground energy storage demonstration project.
Underground energy storage for commercial complexes, office buildings, and hotels;
Backup power for data centers (underground computer rooms);
Energy storage supporting transportation hubs such as subways and tunnels;
Grid renovation in old urban areas (no available ground space).
For customized underground energy storage solutions, technical documents, or on-site project visits, please contact SINJI Energy. We provide full-process services including scheme design, installation guidance, and lifelong technical support, with a 24-hour response commitment.
SINJI mainly sells vanadium battery system, reactor, vanadium electrolyte and perfluoride ion membrane.
