Solar battery storage can store excess daytime solar for use during the evening or during periods of low generation, potentially reducing electricity purchased from the grid. Whether it is worthwhile depends on your energy usage, feed-in tariff, electricity rates, battery size, efficiency, installation costs and how often the battery cycles. Not every system provides blackout backup, so ask whether a compatible inverter and backup circuits are included. Compare quotes from accredited installers, check warranty terms and use current guidance from energy.gov.au before deciding.