There are a lot of different types and wording classifications used to describe solar inverters. We thought a quick review of the most typical type of solar inverter systems would be helpful:
- Solar Grid tie only
- These inverters have no energy storage capability, i.e cannot connect battery storage for loadshedding backup or off-grid operation directly to inverter.
- When the grid power is down, the inverter will not operate, as it requires a reference grid power signal to synchronize and connect with.
- These inverters are grid interactive, i.e. they are connected to the grid and can export excess energy generated by the connected solar PV array and import energy from the grid.
2. Solar Off grid and Hybrid Off grid 
- These inverters are specifically designed to operate without an external grid power connection.
- The hybrid type, consist of both an AC battery charger and inverter therefore the terminology of being Hybrid.
- Most hybrid inverters include solar PV MPPT battery chargers, however some inverters do not contain internal solar PV MPPT battery charger inputs such as Victron, and these systems are required to be fitted with separate solar PV MPPT chargers.
- They are not designed, tested and certified for use with a utility grid connection and typically do not comply to local NRS-097-2-1 requirements or IEC 62116 for safe grid connection
- In accordance with the requirements of the local wiring regulations SANS 10142, these inverters may not be connected the utility grid supply and must be installed with a bypass changeover switch which removes the inverter from circuit when powering loads using grid electrical supply
3. Solar Grid-Interactive Hybrid
- These inverters are designed to operate from utility, battery and solar PV supply simultaneously. They also have the ability to import and export energy with the utility grid.
- They typically integrate Solar PV MPPT battery charger, Grid connected AC battery charger and Inverter. Some inverter systems such as Victron however typically require separate solar PV MPPT charge controllers for battery charging.
- These inverters are required to have NRS-097-2-1 and IEC 62116 approval to ensure safe connection with the utility grid and to comply with the requirements of South African wiring regulations SANS 10142.