Off Grid Solar system using a Sungrow inverter and battery

31 August 2023 by
Off Grid Solar system using a Sungrow inverter and battery
AC Solar Warehouse Pty Ltd, Rob Birchall

Single Phase Sungrow Hybrid Inverters are now supported for use off-grid with generator backup.

Sungrow has recently added a new feature for the Sungrow SHRS inverters to make them available to be used in an off-grid situation with a backup generator to charge batteries if there is not enough solar or a bit of backup is required.

Read the tech brief here: Sungrow Single-Phase Hybrid in Off-Grid - Additional settings for Generator

Supported Inverter Models

The off-grid feature is supported by the following inverter models, all of them single phase hybrid inverters

Note:  Three Phase SHxxRT inverters are also capable of running off grid, however do not support a generator connection at this point.

Design Considerations for Off-Grid Installations

Off-grid installations require careful design. Below is a basic SLD of electrical wiring

Key design aspects include:

1. Inverter Power Output
Ensure there is enough peak and continuous inverter output power available to meet the load demands at the site.

2. Battery Storage Sizing
The battery storage must also be sized to meet energy requirements during periods when there is insufficient solar power available (night time and inclement weather)

3. PV Array Sizing
The PV array must be sized to supply power for the loads during the day with excess available to charge the battery bank. These calculations should be based on the worst-case scenario insolation during the year, generally during the winter solstice for most locations in Australia.

Backup Generator Integration

For periods of low insolation, the inverter can also be used with a 2-wire auto-start backup generator to charge the batteries where there is insufficient sunlight available to keep the batteries full during prolonged periods of inclement weather. The generator should be sized to meet site load requirements and also have spare power to charge the batteries.

Important specifications for Sungrow Hybrid inverters acting in off grid:

For more installation tips about Sungrow Hyrbid inverters you can also explore the  Sungrow Knowledge Base.

Battery Stack Configuration

Sungrow batteries  are stackable in 3.2kWh modules, and can be installed in stacks of minimum 3 units to achieve 9.6kWh storage, or a maximum of 6 units to achieve 19.2kWh of storage per stack.  Battery stacks  can be installed in parallel using the Sungrow battery combiner box where higher storage capacity is required, up to 4 stacks in parallel (76.8kWh max storage per site)

These impressive power output and battery storage specifications from the Sungrow hybrid inverter range will allow for simple and powerful solutions for sites where it is impossible, impractical or expensive to have grid supply.

Official distributor of Sungrow in Australia & New Zealand

For assistance in designing and supplying an off-grid Sungrow solution, feel free to contact our dedicated team. We have Sungrow in-house specialist and our team’s technical knowledge across Sungrow brand and product range, ensures you can navigate any technical issues or support questions.