Estimate your small-scale technology certificates and their dollar value, with zone-aware deeming for your postcode.
Is this for your own site, or do you run a solar business?
Estimate only. Certificate prices fluctuate. Systems up to 100 kW earn STCs under the current rules; above that, an announced federal change extends STC eligibility to 1 MW for installs from 1 October 2026, subject to regulations.
Small-scale Technology Certificates = eligible kW × your postcode's zone rating × the deeming period (years remaining until the scheme ends in 2030). Their dollar value is the certificate count × the market STC price. Northern (sunnier) zones earn more per kW.
Small-scale Technology Certificates are the federal upfront discount on solar under the Small-scale Renewable Energy Scheme. A system up to 100 kW earns certificates for the power it is expected to generate before the scheme winds up at the end of 2030. Announced 5 August 2026: the federal government intends to expand STC eligibility from 100 kW to 1 MW for solar installed from 1 October 2026, subject to regulations being made. The calculator prices that band under the announced design and flags it, so you can see what a commercial system is worth on either side of the change.
In practice you rarely touch the paperwork. Your installer assigns the certificates to a registered agent and passes the value back as a discount at the point of sale, so the STC value is already baked into the price on your quote.
Three things decide how many certificates you earn. System size, where the first 100 kW counts under the current rules and the whole system counts in the announced 100 kW to 1 MW band. Your postcode zone rating, since Australia is split into four zones by sunshine, from 1.622 in the far north down to 1.185 in the cooler south. And the deeming period, the number of years left until 2030 — install earlier and you deem more years, so the certificate count steps down a little each January. The announced mid-scale band is different again: a fixed five years rather than a declining count, for installs from 1 October 2026, subject to regulations.
A 30 kW system in Sydney sits in Zone 3, which rates 1.382. Installed in 2026 it deems five years to 2030: 30 × 1.382 × 5 is about 207 certificates. At roughly $39 each that is close to $8,100 off the install price before you have paid anything.
To claim, the panels and inverter must be on the Clean Energy Council approved product lists and the job signed off by a CEC-accredited installer. The calculator above runs the same sum for your exact postcode, size, and install year.