What changed
The Clean Energy Regulator says amendments to the Small-scale Renewable Energy Scheme took effect for batteries from 1 May 2026. The STC factor now reduces more frequently and the amount of support tapers with usable battery capacity.
The new capacity taper
For eligible capacity, the first 14kWh receives 100% of the applicable STC factor. Capacity above 14kWh and up to 28kWh receives 60%, while capacity above 28kWh and up to 50kWh receives 15%. The broader programme still supports eligible batteries from 5kWh to 100kWh nominal capacity, with certificates calculated on the first 50kWh of usable capacity.
Why this changes quote comparisons
A quote prepared under the old factor can materially overstate the discount for an installation completed after the change, especially for larger systems. The Regulator has stressed that installation date matters and retailers should explain the current calculation clearly.
Do not size a battery around the rebate boundary
The right capacity is the one that fits the household’s solar surplus, evening load, backup target and inverter power. A 30kWh battery can receive less support per incremental kWh than a smaller system and may still be economically sensible for a large load—or unnecessarily expensive for a small one. Model the load first.
What to request from an installer
Ask for usable battery capacity, continuous/peak power, proposed inverter architecture, the STC factor and capacity taper used in the quote, the expected installation date and any state/network requirements. Melnti’s Australia guide and verified battery library provide the research layer.