Recently, COSLINK delivered a 2500kW/4945kWh energy storage system in Dongguan. This project fully utilized COSLINK self-developed Flexible DC Active Control Technology to address the core issue of load imbalance for the customer. 

By implementing a continuous and precise peak shaving and valley filling strategy, the ESS significantly reduced the company’s electricity costs, alleviated the power consumption pressure on the grid, ensuring the stability and efficiency of the power system.

Project Overview

· Project Location: Dongguan City

· Project Scale: 2500kW/4945kWh

· Project Configuration: 5* 625kWpower cabinets, 23* 215kWh active control air-cooling energy storage cabinets, and 1* converging control cabinet.

Project Pain Points

1. Imbalanced Loads and Overload Pressure on Multiple Transformers:

This project includes five 2000kVA transformers in the same distribution room, each with different load levels. Two transformers are operating at 85% load, one transformer is overloaded, one is at 42% load, and the last one is at 33% load.

2. Large load fluctuations requiring real-time adjustment.

Each transformer's daily load power varies significantly, and there is potential for future load adjustments (some transformers may have equipment added or removed). Adjusting the power structure and rewiring would be challenging and costly.

Why Choose Us?

The key challenge of this project is the need to flexibly adjust the energy storage system's charging and discharging resources according to the changes in back-end load power.

Conventional ESS can only adjust the resources connected to their respective transformers, making them unable to adapt to adjustments in the overall distribution system, potentially leading to resource waste or shortages. Conventional ESS struggle to adjust power resources easily and effectively. However, COSLINK “Flexible DC Active Control” energy storage solution effectively addresses issues of unstable power loads and uncertain load power, facilitating system adjustments and expansions.

Why Flexible Energy Storage Can Solve These Issues?

Compared to conventional ESS, the flexible DC active control ESS offers much higher flexibility. While traditional ESS can only utilize the resources of the individual connected transformer.In contrast, the flexible DC active control ESS features COSLINK self-developed “Active-Control Battery Optimization Control System” and “Flexible DC Regulation System”. These two core technologies enable the integration of resources from multiple transformers through a confluence control cabinet, maximizing the utilization of each transformer and effectively eliminating resource waste.

Using a conventional energy storage solution, the configuration for each transformer is:

· Transformer A (85% load rate): Charging power of 250kW/h, can consume (other loads) 1500kW/h, storage configuration of 250kW/550kWh.

· Transformer B (85% load rate): Charging power of 250kW/h, can consume (other loads) 1500kW/h, storage configuration of 250kW/550kWh.

· Transformer C (109% load rate): No charging capacity, can consume (other loads) 1960kW/h, no storage allowed, cannot run overloaded long-term, needs load reduction, and power distribution adjustment.

· Transformer D (42% load rate): Charging power of 1000kW/h, can consume (other loads) 750kW/h, storage configuration of 750kW/1650kWh.

· Transformer E (33% load rate): Charging power of 1200kW/h, can consume (other loads) 590kW/h, storage configuration of 590kW/1300kWh.

Total storage system capacity is 1840kW/4050Wh at most.

Using the Flexible DC Active Control Energy Storage Solution:

· The combined charging capacity of all transformers and energy storage resources is 2700kW/h, with a total power consumption (other loads) of 6300kW/h. The storage system can be configured to 2700kW/6000MWh.

This shows that the energy storage capacity with COSLINK Flexible DC Active Control Energy Storage Solution can reach 6MWh, which is a 33% increase compared to the conventional solution.This also helps alleviate the power supply burden on overloaded transformers. By continuously implementing intelligent peak shifting strategies, COSLINK solution effectively enhances the client's return on investment.

Advantages of the “Flexible” Solution

1. Optimized Installation and Space Utilization

· The distributed system design supports decentralized installations, adapting to various site conditions and reducing space requirements.

2. Dynamic Load Management

· The system has highly flexible load adjustment capabilities,allowing for optimization and allocation based on real-time data and demands. All loads can be adjusted flexibly, providing more distribution adjustment options and simplifying maintenance.

3. Modular Design for Easy Deployment and Maintenance

· Both the PCS and energy storage cabinets feature a modular design. Single modules can be expanded or replaced without affecting the overall system operation, minimizing renovation time and costs.

4. Simplified Expansion

· Each energy storage cabinet is equipped with an advanced battery optimization control system supporting cluster-level management, making system expansion quick and easy without the need for large-scale modifications, thus reducing expansion costs.

5. Increased Efficiency and Lower Construction Costs

· The system design allows for direct connection to a 380V power supply, avoiding the additional investment and operational costs of voltage conversion equipment, making construction and installation simple.

6. Flexible Charging and Discharging Management

· Each transformer is equipped with a power control cabinet, and each power cabinet can utilize all energy storage cabinets, maximizing transformer capacity utilization and making charging and discharging more flexible.

7. Fault Isolation and Redundancy

· Each power control cabinet is equipped with an EMS system, allowing a single power control cabinet to communicate with all energy storage cabinets. If a fault occurs in a single storage cabinet, the system can automatically switch to other cabinets, ensuring uninterrupted operation of the entire system. This approach enhances reliability and safety while minimizing the impact of faults.

8. Precise Performance Management, Extended Lifespan, and Safety Assurance

· The system uses an intelligent active-control optimizer to precisely manage each battery cell, preventing overcharging or deep discharging. This ensures balanced charging and discharging, improves efficiency, enhances overall safety, and extends the system’s lifespan while boosting energy efficiency.

9. Intelligent Real-Time Remote Operations and Maintenance

· Equipped with COSLINK self-developed cloud platform, achieving full-link visualization via app and web interface. Real-time data analysis and remote management enable early warnings, precise maintenance, lower fault rates, and improved operational efficiency, achieving cost-effective and efficient operations.

Conclusion

Since its delivery, the system has been operating autonomously and stably, meeting performance targets and receiving excellent feedback from the client. In comparison, traditional energy storage solutions face challenges in adapting to fluctuating load demands and offer limited arbitrage opportunities. Additionally, future changes in load would necessitate costly line modifications, making it difficult to maximize peak and valley arbitrage and increasing maintenance costs.

On the other hand, the Flexible DC Active Control Energy Storage Solution effectively "collaborates" with each transformer, maximizing their utilization. This approach has shortened the project's payback period to just 3.5 years—compared to an extended recovery period and a 15% decrease in arbitrage benefits with conventional solutions, which suffer from a 33% reduction in storage capacity. This successful implementation has significantly reduced the company’s electricity costs.

COSLINK Commitment

Based on our proprietary active control technology, COSLINK is committed to designing innovative solutions that address our clients' specific challenges. We take a comprehensive approach, considering investment costs, project returns, system safety, and stability to meet our clients' needs. COSLINK is dedicated to partnering with clients to solve their problems and is resolute in becoming a leading global provider of innovative, comprehensive energy solutions.