Small-scale technology certificates (STCs) can reduce the upfront cost of eligible solar panel, battery or other approved systems. The value generally depends on the system’s size, location, installation date and the applicable deeming period, and the installer usually claims and assigns the certificates on your behalf. STC values can change, so the discount is not a guaranteed fixed rebate or cash payment. Ask your installer for an itemised quote and check current eligibility and rules through the Clean Energy Regulator or energy.gov.au.