Most Australian rooftop buyers never create a REC Registry account. Small-scale Technology Certificates are usually created and assigned by the Clean Energy Council–accredited installer (or their trader), with the certificate value deducted from your invoice. Understanding that paperwork trail still protects you when quotes disagree on the “rebate” line.
What STCs are — and what they are not
STCs are tradeable certificates under the Small-scale Renewable Energy Scheme. Their dollar value fluctuates with the market, though many installers quote a fixed discount based on current trading. They are not a cash rebate paid into your bank account after installation, and they are not the same as state battery subsidies.
The number of certificates depends on system size in kilowatts, the installation postcode zone, and the deeming period remaining in the scheme schedule.
Why installers usually handle creation and assignment
Creating certificates requires proof of eligible panels and inverter, installer and designer accreditation, and correct site details. Professional installers already operate in that workflow. Assigning STCs to them (or their agent) in exchange for a price reduction is the common consumer path.
Documents you should still keep
Even when you never touch the registry, keep the signed STC assignment or form of authority, the tax invoice showing the discount, panel and inverter serial lists, and the CEC compliance statement. These matter if certificates are queried or if you later sell the home and a buyer asks how the system was incentivised.
- Confirm who creates and owns the STCs in writing
- Match the quoted kilowatt size to the panels actually installed
- Store serial numbers with the assignment paperwork
- Note the installation date used for deeming calculations
When numbers diverge between quotes
Different traders may assume different STC market prices. Zones can be mis-entered. Panel wattage on the quote may not match the stock that arrives. A few hundred dollars of “rebate” gap is often an assumption gap, not a secret government program.
The STC line is a commercial assumption until serials, zone, and assignment are locked.
Timing and incomplete installs
Certificates generally relate to an eligible installation. Partial installs, delayed inverters, or swapped panel models can stall creation. Do not make final payment until the as-built system matches the paperwork your installer will lodge.
State add-ons sit beside — not inside — STCs
Battery rebates, interest-free loans, and local council programs have separate eligibility and forms. Bundling them verbally as “the rebate” confuses payback models. Ask for STC discount, state incentive, and retail promotions as three separate lines.
If you ever self-create certificates
A minority of owners retain and create STCs themselves. That path needs registry literacy and patience; most households are better served by a transparent assignment discount from a reputable installer. If you do self-create, budget for market price risk and lodgement delays.