The Small-scale Renewable Energy Scheme (SRES) pays installers and owners for renewable energy by creating Small-scale Technology Certificates (STCs). One STC represents one megawatt-hour of renewable electricity a system is expected to produce, or one megawatt-hour of electricity displaced. The certificates are created when the system is installed, assigned by the owner to the installer, and sold, normally to a trader, who passes the money back as cash or as a discount on the job.
This is the whole-of-scheme guide for crews and office staff. Other pages go deeper on each part, and we link them as we go. Everything here reflects the position at the time of writing, 2 October 2026, and the scheme’s official reference is the Clean Energy Regulator (CER).
What the scheme covers
| Technology | Created when | Basis of the count |
|---|---|---|
| Rooftop solar up to 100 kW | Installation | kW, zone rating, deeming period |
| Mid-scale solar above 100 kW up to 1 MW (installed from 1 October 2026) | Installation | kW, zone rating, fixed five-year deeming |
| Solar water heaters and air-source heat pumps | Installation | Model, zone, deeming period |
| Home batteries 5 to 100 kWh usable (up to 50 kWh counted) | Installation | Usable kWh, tiers, factor |
Small solar is still the volume. Batteries joined on 1 July 2025 through the Cheaper Home Batteries Program, and mid-scale solar joins for systems installed from 1 October 2026. Above 1 MW, systems remain in the large-scale scheme and create LGCs.
The maths for rooftop solar
STCs for solar = system kW x zone rating x deeming years, rounded down.
Zone ratings for the four zones are 1.622 (zone 1), 1.536 (zone 2), 1.382 (zone 3) and 1.185 (zone 4). Sydney, Brisbane, Perth, Adelaide, Canberra, the Gold Coast, Newcastle, Wollongong, Cairns and Townsville sit in zone 3. Melbourne, Geelong, Hobart and Launceston are zone 4. Darwin is zone 2 and Alice Springs zone 1. The CER postcode table is the authority, and the zone ratings explainer shows how to look it up.
The deeming period is five years for 2026 installs, four for 2027, and falls by one a year to a single year in 2030. For a 6.6 kW system installed in 2026:
| Zone | Rating | STCs (6.6 x rating x 5) | Value at $38 |
|---|---|---|---|
| 1 | 1.622 | 53 | $2,014 |
| 2 | 1.536 | 50 | $1,900 |
| 3 | 1.382 | 45 | $1,710 |
| 4 | 1.185 | 39 | $1,482 |
In 2027 the same system in zone 3 creates 36 STCs (6.6 x 1.382 x 4 = 36.5), a loss of about $340 per job at $38. See what changes in January and the full deeming schedule.
Batteries, hot water and mid-scale
Batteries. The count is usable kWh through three tiers (first 14 kWh at 100%, 14 to 28 at 60%, 28 to 50 at 15%) multiplied by a factor: 6.8 at the time of writing, 5.7 from 1 January 2027, 5.2 from 1 July 2027. A 13.5 kWh battery creates 91 STCs. The battery must be CEC-approved and VPP-capable, installed by an accredited installer, one per property. See the tier explainer.
Hot water. Air-source heat pumps and solar water heaters create STCs by registered model and zone. In Victoria the same job may also create VEECs. See heat pump STCs explained and the hot water STCs page.
Mid-scale. Solar above 100 kW and up to 1 MW installed from 1 October 2026 creates STCs with a fixed five-year deeming period. CER says applications open mid to late November 2026. A 250 kW system in zone 3 would create 250 x 1.382 x 5 = 1,727 STCs, roughly $65,600 at $38. The pillar page is mid-scale solar STCs.
Who does what
- The owner is the person who owns the system and holds the right to the certificates. Most owners assign that right to the installer on a signed form so the installer can discount the quote.
- The installer must be accredited (for solar, through Solar Accreditation Australia), install to the standards, and keep the evidence.
- The registered agent or trader lodges the claim in the REC Registry and buys the certificates.
- The CER validates, audits and can claw back certificates created in error.
Ownership questions come up often, so we cover them in who owns the STCs.
From job to cash: the short version
- Quote with the STC discount shown.
- Collect the assignment form and photos on site.
- Create the certificates in the REC Registry, or give the file to your trader to do it.
- The CER validates, and the trader pays.
The step-by-step detail is in how to claim STCs. Our how it works page shows the same flow from a trader’s side.
The money: clearing house and spot
The CER’s STC Clearing House sells certificates at a fixed $40 (ex GST), which acts as a ceiling. The spot market has been roughly $38 to $40 in 2026. Traders pay below spot to cover their risk, and the gap is where the competition is. We never publish rates in articles; the current rate is on the pricing page. A longer view of the market is in STC price history.
Where jobs go wrong
- Wrong zone, wrong deeming year or capacity entered in the claim.
- Missing or unsigned assignment form.
- Photos without geotag or serial detail.
- Installing after a product has been removed from the approved list.
- Duplicate claims for the same system.
The top rejection reasons and compliance guide cover each in depth.
The end date
The scheme ends on 31 December 2030. That does not mean the work dries up, because batteries, hot water and mid-scale solar all sit inside it. It does mean the value per job shrinks each year on solar, and cash flow discipline matters more. See what happens when the scheme ends.
Terms you will hear
A few words come up in every conversation with a trader or the CER.
- Deeming period. The years of output counted when certificates are created. See deeming period.
- Zone rating. The multiplier for your postcode’s sunshine. See zone rating and how to find your postcode’s zone.
- Liable entity. The electricity retailer that must surrender STCs each year. See liable entity.
- REC Registry. The CER’s online system where certificates are created, held and transferred. See REC Registry.
- Registered agent. A person or business registered to act in the registry on an owner’s behalf. See registered agent.
- STP. The Small-scale Technology Percentage, set annually, which fixes how many STCs retailers must surrender per MWh sold. A 2026 figure of about 11.67% has been reported.
If a term is missing, the certificate trading glossary and the glossary cover the rest. Knowing the vocabulary helps you read a contract and ask better questions of a trader.
What to do next
- Check the zone, deeming year and capacity on your next quote.
- Add a “claim ready” checklist to every job pack.
- Compare traders on settlement time, fees and contract terms with the checklist for choosing a trader.
- Look up unfamiliar terms in the glossary.
- When you want a desk that pre-checks and settles claims, start trading.