The optical storage system mainly has two kinds of connection schemes, DC coupling and AC coupling. At present, the two methods have been relatively mature in technology, each has advantages and disadvantages, and are suitable for different application scenarios.
Photovoltaic inverters and bidirectional converters are integrated into optical storage machines, and are directly connected with photovoltaic modules, power grids, batteries, etc., to form a whole. When the photovoltaic system is running, the power generated can be charged to the battery through the optical storage unit, and can also be used to power the load or input to the grid.
Advantages:
High Efficiency: Minimizes energy loss because power remains in DC during charging and discharging.
Simpler Design: Fewer components since it doesn’t require a separate battery inverter.
Lower Installation Costs: Especially in new systems.
Disadvantages:
Limited Retrofit Options: Not ideal for adding batteries to an existing system with a standard solar inverter.
System Dependency: Components are interdependent, so a failure in one can impact the entire system.
Best For:
New solar-plus-storage installations.
Off-grid or standalone systems requiring high efficiency.
Includes photovoltaic system and energy storage system two parts. Photovoltaic system consists of photovoltaic array and photovoltaic inverter; The energy storage system consists of an energy storage inverter and a battery. The two systems can operate independently and not interfere with each other, or they can be separated from the grid to form a microgrid system. When the photovoltaic system is running, the power generated can be powered by the photovoltaic inverter for the load or input to the grid, and can also be charged by the energy storage inverter for the battery.
Advantages:
Flexibility for Retrofitting: Easy to add batteries to an existing solar system.
Independence of Components: Solar and battery systems can work separately.
Backup Power: Can power critical loads during grid outages.
Disadvantages:
Double Conversion Losses: DC to AC and back to DC during storage reduce efficiency.
Higher Installation Costs: Requires separate inverters for solar and batteries.
Best For:
Upgrading existing solar installations with battery storage.
Systems requiring grid-tied and backup power functionality.
| Feature | DC Coupled | AC Coupled |
| Energy Flow | DC → DC | DC → AC → DC (battery) |
| Efficiency | Higher due to direct DC usage | Lower due to double conversion |
| Retrofit Suitability | Limited | Excellent |
| Backup Power | Possible with hybrid inverter | Possible with hybrid inverter |
| Cost | Lower (for new systems) | Higher |
The optical storage system mainly has two kinds of connection schemes, DC coupling and AC coupling. At present, the two methods have been relatively mature in technology, each has advantages and disadvantages, and are suitable for different application scenarios.
Photovoltaic inverters and bidirectional converters are integrated into optical storage machines, and are directly connected with photovoltaic modules, power grids, batteries, etc., to form a whole. When the photovoltaic system is running, the power generated can be charged to the battery through the optical storage unit, and can also be used to power the load or input to the grid.
Advantages:
High Efficiency: Minimizes energy loss because power remains in DC during charging and discharging.
Simpler Design: Fewer components since it doesn’t require a separate battery inverter.
Lower Installation Costs: Especially in new systems.
Disadvantages:
Limited Retrofit Options: Not ideal for adding batteries to an existing system with a standard solar inverter.
System Dependency: Components are interdependent, so a failure in one can impact the entire system.
Best For:
New solar-plus-storage installations.
Off-grid or standalone systems requiring high efficiency.
Includes photovoltaic system and energy storage system two parts. Photovoltaic system consists of photovoltaic array and photovoltaic inverter; The energy storage system consists of an energy storage inverter and a battery. The two systems can operate independently and not interfere with each other, or they can be separated from the grid to form a microgrid system. When the photovoltaic system is running, the power generated can be powered by the photovoltaic inverter for the load or input to the grid, and can also be charged by the energy storage inverter for the battery.
Advantages:
Flexibility for Retrofitting: Easy to add batteries to an existing solar system.
Independence of Components: Solar and battery systems can work separately.
Backup Power: Can power critical loads during grid outages.
Disadvantages:
Double Conversion Losses: DC to AC and back to DC during storage reduce efficiency.
Higher Installation Costs: Requires separate inverters for solar and batteries.
Best For:
Upgrading existing solar installations with battery storage.
Systems requiring grid-tied and backup power functionality.
| Feature | DC Coupled | AC Coupled |
| Energy Flow | DC → DC | DC → AC → DC (battery) |
| Efficiency | Higher due to direct DC usage | Lower due to double conversion |
| Retrofit Suitability | Limited | Excellent |
| Backup Power | Possible with hybrid inverter | Possible with hybrid inverter |
| Cost | Lower (for new systems) | Higher |
