Why Grid-Tie with Backup?
Grid-Tie has the financial benefits.
But now you want the essentials running when Eskom is not available.
Can be upgraded to let more appliances run Independent of Eskom.
This configuration is the Best of Both approach. The financial viability of a Grid-Tie, with a Backup that is upgradable to reach total independence.
You can decide how far you want to go.
You can start with a Grid-Tie only, and add the Backup later. This allows the savings to start immediately, then the backup can be added when necessary.
More than just backup
The Backup Inverter allows for the Grid-Tie to be functional without Eskom. Excess Solar Power is used to charge the batteries - to give the Off-Grid Effect.
The system can be upgraded to become a fully Off-Grid System.