STC Calculator 2026
Calculate your solar rebate instantly. See how many STCs (Small-scale Technology Certificates) your system will generate and your estimated savings.
Solar rebate calculator
Enter your details to calculate your STC rebate.
Your estimated solar rebate
- System size
- 6.6 kW
- STCs generated
- 45
- Based on Zone 3 × 5 year deeming period (2026)
- Your solar rebate
- $1,710
- At $38/STC (current market rate)
Estimate only. STC prices fluctuate daily. Final rebate confirmed at installation.
Claim your $1,710 rebate
Get an accurate quote with all available rebates included.
How the solar rebate (STCs) works
System installed
You install a SAA-approved solar system with an accredited installer.
STCs created
Based on system size and location, STCs are created for your system.
Assigned to installer
You assign STCs to your installer in exchange for an upfront discount.
Rebate applied
The STC value is deducted from your quote as a point-of-sale discount.
What are STCs?
Small-scale Technology Certificates (STCs) are the mechanism behind the solar rebate in Australia. They're created when you install an eligible renewable energy system and represent the amount of electricity your system is expected to generate until 2030.
Energy retailers are required to purchase STCs, creating demand that gives them value. When you install solar, you can assign your STCs to your installer in exchange for an upfront discount on your system price.
Why the rebate is decreasing
The solar rebate decreases each year based on a scheduled deeming period. The formula is:
STCs = System kW × Zone Rating × Deeming Period
2026 deeming period: 5 years (down from 6 in 2025). This reduces rebates by approximately 15 to 20% compared to 2025.
The deeming period decreases annually: 4 years in 2027, 3 in 2028, 2 in 2029, and 1 in 2030. By 2029, the rebate will be about 60% less than 2026, so installing sooner keeps more of it.
STC zones in Australia
| Zone | Multiplier | Where |
|---|---|---|
| Zone 1 | 1.622 | Highest solar irradiance (Alice Springs, Karratha, Port Hedland, Coober Pedy) |
| Zone 2 | 1.536 | High solar irradiance (Darwin, Mount Isa, Broome, Geraldton) |
| Zone 3 | 1.382 | Moderate solar irradiance (Sydney, Brisbane, Perth, Adelaide, Canberra, Cairns, Townsville) |
| Zone 4 | 1.185 | Lower solar irradiance (Melbourne, Hobart, Albany, Cooma) |
A sunnier zone means more STCs and a bigger rebate
Zones with more sunshine (like Zone 1 in Alice Springs) generate more STCs per kW of solar installed. This means homes in Zones 1 and 2 receive a larger solar rebate than homes in Zones 3 and 4, though the rebate is still significant everywhere.
STC calculator FAQ
How accurate is this STC calculator?
This calculator provides a close estimate based on standard STC formulas. The actual rebate may vary slightly based on exact installation date, current STC market prices, and system specifications. Your installer will confirm the exact amount.
What is the current STC price?
STC prices fluctuate based on market supply and demand. Currently, STCs are trading around $38 each. The government sets a ceiling price of $40 but the market rate is typically $35 to $40.
When does the solar rebate end?
The STC scheme runs until 2030, but the rebate value decreases each year. By 2029, the rebate will be approximately 75% lower than in 2026. Installing sooner means a larger rebate.
Can I claim STCs myself instead of assigning them?
Technically yes, but it's complicated. You'd need to create an account with the Clean Energy Regulator, create the certificates yourself, and find a buyer. Most people assign STCs to their installer for an immediate discount.
Do STCs apply to battery installations?
STCs only apply to solar panels, not batteries. However, the separate federal battery rebate (Cheaper Home Batteries) provides approximately 30% off eligible battery systems.
The rebate drops every 1 January
Get a free quote now and see exactly how much you can save with all available rebates.
How this STC calculator works
Enter your postcode and planned system size. The calculator determines your STC zone, multiplies by the current deeming period (years remaining until 2031), and applies the current STC market price to show your rebate value in dollars.
Your installer typically claims the STCs on your behalf and applies the discount to your invoice. This means you see the rebate as a lower upfront system price rather than a separate payment.
Common questions
What are Small-scale Technology Certificates (STCs)?
STCs are a form of government incentive for installing renewable energy systems in Australia. When you install solar panels, your system generates a set number of certificates based on its expected output over the deeming period. These certificates have a market value (roughly $38 to $40 each in 2026) and are typically traded by your installer to give you an upfront discount on your system price.
How much is the STC rebate worth in 2026?
For a typical 6.6kW system in zone 3 (most of Australia), the STC rebate is worth about $1,710 in 2026 (45 certificates at $38). Larger systems receive more STCs. The value decreases each year as the deeming period shortens, reaching zero in 2031.
What are STC zones and how do they affect my rebate?
Australia is divided into four STC zones based on solar irradiance. Zone 1 (Alice Springs and Karratha) receives the most sunshine and generates the most STCs per kilowatt. Zone 4 (Melbourne and Hobart) receives the least. Most of mainland Australia, including Sydney, Brisbane, Perth and Adelaide, falls in zone 3. Your postcode determines your zone, which this calculator looks up automatically from the Clean Energy Regulator's zone table.