Grid connected energy storage system and off grid energy storage system is different type of energy storage system. Their main differences lie in the connection method and operating mode.
Grid connected energy storage system refers to the connection between the energy storage system and the power grid, which enables bidirectional interaction with the power grid. It can obtain electrical energy from the power grid for storage, and can also output electrical energy to the power grid for power supply or participate in power grid scheduling and energy trading. The grid connected energy storage system needs to comply with the regulations and requirements of the power grid, ensure the safe and stable operation of the system, and have high technical and standard requirements.
Off grid energy storage system is an independent energy storage system that operates independently and is not connected to the power grid. It is mainly used for independent power supply scenarios, such as remote areas, islands, mobile facilities, etc. Off grid energy storage systems can be charged through renewable energy sources such as solar and wind energy, achieving independent power supply. It is not limited by the power grid and does not require grid scheduling and trading. It is suitable for some special scenarios and needs, and can independently handle local power demands.
The process of grid connected energy storage system includes the following steps:
1. On site survey: organized by relevant professional organizations to survey the installation site and evaluate whether it meets the grid connection conditions.
2. Develop a plan: Based on the survey results, develop a specific access system plan, including the voltage and connection method for grid connection.
3. Review plan: Review the access plan to ensure compliance with relevant standards and requirements.
4. Installation and debugging: Install and debug the equipment according to the plan, ensuring that the energy storage system, inverter, control system, and other equipment operate normally and meet the requirements of power grid connection.
5. Grid connection debugging: Conduct grid connection debugging on the system to ensure stable connection with the power grid, normal energy conversion and output. The system is officially connected to the grid and is beginning to achieve bidirectional flow of electricity.

6. Operation monitoring: Conduct system operation monitoring and data recording to ensure normal operation of the system, participate in power grid scheduling and energy trading.

The advantages of grid connected energy storage systems include:
1. Energy optimization and utilization: Energy storage systems can participate in power grid scheduling, utilize the stability and reliability of the power grid, provide guarantees for energy storage equipment, and achieve optimal utilization of electricity.
2. Energy conservation: Energy storage and output through energy storage systems can achieve efficient utilization and conservation of energy.
3. Peak shaving and valley filling: Energy storage systems can store electricity during peak periods and output electricity during low periods, balancing grid load and reducing grid operating costs.
The grid connected energy storage system has multiple operating modes, such as maximum self use, TOU (time of use electricity price), and full grid connection. Users can set and adjust according to their actual needs. In addition, the system also has functions such as charge and discharge management, battery monitoring, etc., making it convenient for users to manage and maintain.
Grid connected energy storage systems and off grid energy storage systems have their own characteristics and advantages, and users can choose the appropriate system type according to their own needs. For grid connected energy storage systems, their grid connection process is relatively complex, but they have many advantages and can bring users a better electricity experience and economic benefits. Especially grid connected energy storage systems have important advantages in improving grid stability, energy conservation, and peak shaving and valley filling.