There are some advantages and disadvantages of AC Battery Storage. A representative schematic for this kind of solution is shown below;
In this system the battery is connected to the AC side of the Solar PV system. This requires an additional battery inverter/charge controller to convert AC power to DC to store in the battery and vice versa when required to be used in home. Advantage for this configuration is that there is no impact on the feed in tariff payments, i.e. no reduction in FIT payments due to losses in converting AC to DC and vice versa. Also the warranties on the Solar PV system will still remain effective if the batteries are being retrofitted.
Another advantage is that you can benefit from economy 7 charging at discounted retes if you have an Economy 7 meter installed (please check it with your energy supplier).
- Additional inverter required which increases the costs
- Conversion of AC power to DC and then back to AC increases the losses.
- DNO approval needs to be obtained
Following are different AC side battery storage solutions available for you to choose;
RESULG Chem RESU H series batteries have a nominal voltage of 400 VDC and are available in two versions suitable for use either with the SMA Sunny Boy Storage inverter (DLT type) or the SolarEdge StorEdge systems (SEG type).
Expand with additional battery power as needed
- Ideal for grid-connected systems
- Connect up to three high-voltage batteries
- Integrated Secure Power Supply function
- Fully automatic backup function for supplying electricity to the complete home (optional)
- The integrated service package SMA Smart Connected for automated monitoring of battery inverters
SOFAR SOLAR battery storage inverters combined with the PYLONTECH batteries makes a powerful AC side storage system.
Simple and Reliable
- Exchanges energy via the electrical grid, no coupling with the PV inverter, mature technology, simple and reliable.
- Can integrate with all grid-tied renewable systems, including solar, wind, fuel cell etc.
- Supports stand alone mode (like UPS),Ensures the safe operation of the critical load.
- Programmable multiple operations modes:Grid tie,Off grid,and grid-tie with backup.
- Provides a full solution for enerfy consumers to maximize the use of their generated solar energy.
- Increases self-consumption rate(from 20% to 70%).
- User-adjustable battery charging current suits different types of batteries.