The main commercial solar rebate in Australia is the STC discount under the Small-scale Renewable Energy Scheme, and in 2026 it got much bigger in reach. From 1 October 2026, solar PV above 100 kW and up to 1 MW installed from that date can create STCs, with a fixed five-year deeming period. Before that, anything above 100 kW sat in the large-scale scheme and earned LGCs slowly over years at a fraction of the value.
This page sets out what the rebate is, what it is worth by system size, who qualifies and what else to look for. It reflects the position at the time of writing, 2 October 2026. Always check the Clean Energy Regulator (CER) for the final rules, which the CER says it will publish ahead of applications opening in mid to late November 2026.
What qualifies
- Solar PV installed from 1 October 2026 for the 100 kW to 1 MW range. Up to 100 kW has qualified for years.
- Accredited design and installation, through Solar Accreditation Australia (SAA), with Clean Energy Council approved panels and inverters.
- Compliance with state electrical safety rules, network connection agreements and planning approvals before the installation date counts.
- Above 1 MW, the system remains a power station creating LGCs.
The pillar page is mid-scale solar STCs, and the SRES expansion explainer and 1 MW guide have more.
What it is worth
The calculation: kW x zone rating x deeming years, rounded down. Zone ratings are 1.622 (zone 1), 1.536 (zone 2), 1.382 (zone 3) and 1.185 (zone 4). Zone 3 includes Sydney, Brisbane, Perth, Adelaide, Canberra and the Gold Coast. Zone 4 includes Melbourne, Geelong and Hobart. Darwin is zone 2.
| System | Zone | Deeming | STCs | Value at $38 |
|---|---|---|---|---|
| 30 kW | 3 | 5 (2026, small-scale) | 207 | $7,866 |
| 99 kW | 3 | 5 (2026, small-scale) | 684 | $25,992 |
| 99 kW | 3 | 4 (2027, small-scale) | 547 | $20,786 |
| 250 kW | 3 | 5 (mid-scale, fixed) | 1,727 | $65,626 |
| 500 kW | 3 | 5 (mid-scale, fixed) | 3,455 | $131,290 |
| 500 kW | 4 | 5 (mid-scale, fixed) | 2,962 | $112,556 |
| 1 MW | 3 | 5 (mid-scale, fixed) | 6,910 | $262,580 |
Two features stand out. First, the deeming period for mid-scale systems is fixed at five years under the 2026 changes, so unlike the small-scale deeming it does not step down each January. Second, the step from 99 kW to 250 kW more than doubles the STC value, so the old reason to design to 99 kW has gone.
STCs have traded around $38 to $40 recently, with a clearing house ceiling of $40, so a 250 kW zone 3 system is worth roughly $65,600 to $69,000. Reports of the policy cite about $68,000 for a 250 kW system and $136,000 for 500 kW, which fits those figures. The discount is paid when certificates are created and sold, so the installer or owner carries it until then. Use the STC calculator for your postcode.
What it does to payback
On an illustrative cost of $1.00 per watt, a 250 kW system costs $250,000. After about $65,600 of STCs the net cost is about $184,400, roughly a quarter off. If the system saves about $63,750 a year, payback falls from about 3.9 years to about 2.9 years. Real figures depend on your load, tariff, export and quote. See commercial solar PPAs explained for the full worked comparison.
Above 1 MW: LGCs
A system above 1 MW is accredited as a power station and creates one LGC per MWh generated. LGC spot has been roughly $6 to $9 in September 2026, after a low near $4 in February. A 1.5 MW system generating about 2,250 MWh creates 2,250 LGCs a year, about $18,000 at $8. See LGC vs STC and how to sell LGCs.
State and local support
Some states and territories run grants, loans or incentives for business, agricultural and community solar. They change often and some are short-lived, so confirm the current position on your state government’s energy or business pages. In Victoria, the Victorian Energy Upgrades program is run by the Essential Services Commission and covers specific energy efficiency activities. In NSW, a commercial battery incentive has been reported from 1 September 2026. We do not quote dollar amounts for state schemes.
Tax
Treatment of solar equipment, STC income and depreciation depends on the business structure. A rebate delivered as a discount is generally part of the price. Ask your accountant about depreciation, GST on the sale of certificates and any instant asset write-off that applies to your turnover in the relevant year. Do not rely on a solar salesperson for tax advice.
Common mistakes
- Sizing to 99 kW out of habit. The expansion removes the reason.
- Counting the discount before eligibility is clear. Confirm the installation date and the claim route.
- Ignoring site constraints. Network connection limits, export caps and roof structure matter more than the certificate maths.
- Forgetting the installer’s accreditation. Mid-scale needs SAA accreditation and approved products.
- Treating a PPA price as free of certificates. The provider owns them.
For installers and EPCs
If you quote commercial roofs, you can now put a larger discount on a larger system, which helps close deals. Plan for claims of tens of thousands of dollars, and check your trader’s capacity and pre-checks. The cash flow guide shows the effect of settlement terms. See commercial solar rebate in Australia for a shorter answer.
Rebate versus finance
Many businesses pay for solar through an equipment loan or lease, not cash. The rebate fits finance well because it lands at the front. If a lender funds $250,000 and the STC claim returns about $65,600 within weeks of the claim opening, the business can use that to pay down the loan or fund the next phase. Ask the lender or lessor whether it will accept an assignment of the certificates, and whether the repayments are set on the gross or the net cost.
Be careful with timing. Systems installed in October cannot have certificates created until applications open in mid to late November, so the finance must carry the full price until then. Ask the installer for a written timeline: installation date, expected lodgement date, who pays whom and when. If the arrangement relies on the STC payment to meet the first repayment, build in a buffer.
For the owner’s view of what changed on 1 October, see what the expansion means, and for the earlier rules on large systems, LGC vs STC.
What to do next
- Run your site through the STC calculator at several system sizes.
- Ask installers for the STC discount as a line, with the installation date and who lodges.
- Check the CER’s mid-scale page for the application opening.
- If you install commercial solar, see pricing and how it works, then start trading.