The STC scheme asks installers to do four things well: install to standard, document the job, claim within the window and keep records for as long as the regulator may ask. Everything else, the rates, the zones, the deeming period, is arithmetic. What separates installers who bank certificates cleanly from those who chase payments is the discipline behind those four duties.
This is the practical rulebook, written for the person who runs the business or the back office rather than the policy analyst. It sets out what the scheme requires, where installers most often slip, and the calendar dates that move your numbers. For the market and price side of the picture, read STC trading explained.
Duty 1: be accredited for the work you perform
To create STCs on a solar installation, the person who designed and installed it must hold current accreditation for that work through Solar Accreditation Australia (SAA). Batteries require installers who meet the program’s accreditation requirements, and the battery must be CEC-approved and VPP-capable. Electricians are often the licence-holder on site, but the accreditation, not the electrical licence alone, is what the claim rests on. See the answer on whether electricians need solar accreditation.
If an accredited person’s name is on a job they did not do, the claim is at risk. The regulator has taken a firm line on installer attendance and supervision. The answer on installer attendance requirements explains the expectation.
Duty 2: install to standard with approved products
Panels and inverters must be on the Clean Energy Council’s approved lists on the date of installation. The installation has to comply with the relevant Australian Standards (for solar, AS/NZS 5033 and AS/NZS 4777, alongside wiring rules) and local electrical regulations, and the electrical safety certificate for the job must be on file. Batteries add AS/NZS 5139 requirements. See AS/NZS 5139 for battery installations.
Products come off the list. A model approved last year may not be approved on the date you install it, so check the list on the installation date, not the order date.
Duty 3: document the job
Evidence is the currency of the scheme. At minimum, expect to hold:
- Photos showing the array, inverter, labels and serial numbers, with location data.
- The signed assignment form from the system owner.
- The electrical safety certificate and any network (DNSP) approval.
- Product serial numbers, matched to the claim.
- The installer’s written statement where required.
The STC photo requirements resource and the assignment form guide set out what good looks like. A crew that builds the photo set into the job, rather than into the admin afterwards, rarely has a problem.
Duty 4: claim within 12 months
Certificates must be created in the REC Registry within 12 months of the installation date. Miss that and the entitlement lapses. The deadline sounds generous until you consider a stack of jobs awaiting a missing form from one customer, or a claim that has been rejected and needs rework. Track installation date, claim date and status for every job, and review anything older than six months.
Dates that change your numbers
| Date | What changes |
|---|---|
| Daily | Spot and trader rates move |
| 1 Jan each year | Deeming period falls by one year (5 in 2026, 4 in 2027) |
| 1 Jan 2027 | Battery STC factor falls from 6.8 to 5.7 per kWh |
| 31 Dec 2030 | Scheme ends |
A 6.6 kW zone 3 system earns 45 STCs in 2026 and 36 in 2027. That is a 20 per cent reduction in certificates on the same roof. See STC deeming period 2027: what changes in January.
Audits and clawback
The Clean Energy Regulator checks claims at registration and audits installations afterwards. If it finds a system was not eligible, or evidence is inadequate, it can cancel the certificates. If those have already been sold, the commercial consequence depends on your agreement with the buyer. Read the clause. The answers on STC clawback and who is responsible for a failed audit explain how it typically plays out, and our audit guide covers the process.
Who does the claiming
Installers can claim as the registered person themselves, or work through a registered agent that creates and trades on their behalf. Becoming a registered person in the REC Registry takes time because the regulator verifies identity, so many businesses use an agent and pass the work through a trader. Energy Merchants works as that partner; our compliance desk pre-checks each claim before lodgement. Either path is legitimate. What matters is that you know which entity is responsible for what.
Money, tax and paperwork
The sale of STCs is a taxable supply, and the buyer normally issues a recipient-created tax invoice on your behalf. Your ABN and GST registration must be in order. See RCTI, GST and ABN for STC payments. Keep invoices and settlement statements with the job file.
Common slips that cost installers money
Letting the accredited person’s role blur. In many small crews the accredited installer is also the owner, the estimator and the person chasing payments. The regulator wants to see that the accredited person did the work or properly supervised it. Document who attended the site and when.
Treating photos as admin. Photos taken at the end of the day from memory are the single biggest source of avoidable rejections. Our solar installation photo checklist breaks the shots down by stage so the crew captures them in the order they work.
Quoting off an old deeming year. A sales template written in December that still says five years in January is a pricing error on every job it touches.
Mixing installation types. A new system, an addition and a replacement follow different rules. Tag the job correctly at quote stage rather than guessing at the registry. See installation type: new, replacement or additional.
A weekly routine that keeps you inside the rules
- Monday: list every job installed in the last 14 days and its claim status.
- Midweek: chase missing assignment forms, certificates and photos by name.
- Friday: lodge everything complete, and note anything older than 60 days with a reason.
- Monthly: reconcile STC income against installs, and review anything outstanding from the 9-month mark.
It sounds like a lot until you see the cost of a missed deadline. A business doing 30 jobs a month with a typical $1,700 of certificate value per job has about $51,000 passing through the scheme monthly. A small routine protects a lot of cash.
What to do next
Read the STC trading pillar for the full installer overview, and the how it works page for the settlement path. Then run your own business against the STC compliance checklist. If you want a named account manager and a rate locked at lodgement, the Partner Program sets out the tiers.