Guidance, not advice. General information only — STC prices and rebate amounts are time-sensitive and change. Confirm current values with the Clean Energy Regulator (CER), state program websites, or an accredited installer. Figures are as at May 2026.
Solar incentives come in two layers: the federal STC discount (which the installer usually handles and takes off the upfront price) and state rebates/loans on top. Here is how each works and how they stack.
The federal layer — STCs under the SRES
The Small-scale Renewable Energy Scheme (SRES) rewards eligible small systems (rooftop PV, small batteries, solar and heat-pump hot water) with Small-scale Technology Certificates (STCs). It is legislated to run until 31 December 2030.
- One STC = one megawatt-hour of eligible generation, storage or displacement. For PV: STCs = system size (kW) × your zone rating × the deeming period (years), rounded down.
- Most rooftop solar is "deemed" — the system's lifetime certificates (out to 2030, up to 15 years) are created upfront, so the value shows as an immediate discount.
- Because the deeming period is the years remaining to 2030, the STC count for an identical system drops every 1 January. A job slipping into a new year claims fewer STCs even at the same size — so manage the timing in your quoting.
How the discount actually reaches the customer
The customer legally owns the right to create STCs, but in practice they assign them to the installer (or a registered STC agent) in exchange for an upfront discount. Your workflow:
- Calculate the expected STCs and a dollar value using a negotiated or market STC price.
- Show it as a line-item discount on the quote.
- Get the owner to sign an assignment form.
- Register and trade the certificates after install (directly or via a broker) on the CER's REC Registry — within 12 months of installation.
STC price: STCs trade on a market, so the dollar value floats. The CER runs an STC Clearing House at a fixed $40 per certificate (excluding GST), but cashflow timing and whether you achieve that price depend on conditions — so the internal STC price you build into a quote is a commercial decision, not a legislated figure. Always date-stamp any worked dollar example.
Your compliance responsibilities
The customer is the legal owner, but the installer carries the admin and the risk:
- Only promise STC value once the products are on the approved list and the installer holds current accreditation (see Becoming a Solar PV Installer).
- Keep the evidence — signed assignment forms, proof of purchase, design data, commissioning records, photos, accreditation details.
- Register within the creation period and respond to CER queries. The CER audits and inspects, and can require false or non-compliant STCs to be surrendered, impose penalties, or suspend participants. Even if a broker lodges for you, you are responsible for the accuracy of the job data.
The state layer (framework only — these change with budgets)
States add their own rebates, interest-free loans, feed-in-tariff settings or battery incentives — and most are designed to stack with STCs (STC discount first, then the state rebate/loan on the remainder). They open, change and close with budgets, so treat them at a framework level and send people to the official site.
Solar Victoria is the most formalised: a solar PV rebate of up to $1,400 plus a matching interest-free loan for eligible owner-occupiers (and some rentals), with separate battery and hot-water streams. Eligibility includes a property value under $3 million, no PV rebate on that address in the last 10 years, and pre-approval. From 1 July 2026 the household income cap tightens to $150,000 a year (down from $210,000). Installers must register, follow the code of conduct, pre-approve customers and submit to the portal — non-compliance means removal from the approved list. Other states vary widely; Tasmania, for example, has no separate ongoing state solar rebate and relies on the federal STCs. (Solar Victoria sits in the Working in Victoria hub too.)
Common mistakes
- Quoting an STC dollar figure without date-stamping it (the price floats and the deeming year changes every January).
- Missing the 12-month STC creation window after install.
- Promising a state rebate that has closed or changed eligibility — always check it's actually open.
- Assuming the state rebate replaces the STC discount; they stack.
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