According to the Solar Choice Price Index, the average cost of a 5kW solar system in Australia as of September 2025 is about $1. 13 per watt – or about $5,110 – after the STC rebate has been deducted and including GST.
This IR clarifies the requirements for structural support of solar systems, anchorage of solar systems, solar support frame systems, balance-of-system (BOS) equipment, and building-integrated photovoltaic (BIPV) roofing systems.