Small-scale Technology Certificates (STCs) are the tradeable certificates behind Australia's federal rooftop solar discount under the Small-scale Renewable Energy Scheme (SRES). For systems up to 100kW, your installer usually assigns the certificates at sale and reduces your invoice by their market value. In 2026 the deeming period is short — only four years remain until the scheme ends in 2030 — so the upfront discount is smaller than early-2020s quotes, but still material.
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Indicative 2026 pricing: a typical 6.6kW system often quotes around $5,000–$8,000 after the STC discount (metro installs often $5,000–$7,500; premium/regional can run higher). See our solar cost guide.
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Certificates scale with system size (kW), your postcode's STC zone rating, and the remaining deeming years for the installation year. Using MrSolar's 2026 reference maths (spot about $39.85 as of 5 August 2026), a typical 6.6kW system is worth roughly $1,435 in Zone 3 capitals (Sydney, Brisbane, Perth, Adelaide, Canberra), about $1,235 in Zone 4 (Melbourne, Hobart), and more in higher-sun northern zones. Exact certificate counts are rounded per Clean Energy Regulator rules — treat brochure figures as estimates until the assignment form is issued.
Most homeowners assign STCs to the retailer/installer for an immediate discount. You can create and sell certificates yourself via the REC Registry, but you carry price risk, timing risk and admin. Unless you already trade environmental certificates, assignment is usually cleaner. Demand the STC dollar line as a separate item on the quote so you can compare installers fairly.
The SRES deems a block of future generation upfront. That block falls each 1 January and reaches zero in 2030. Waiting a year permanently reduces the federal discount for the same array size and zone. Battery support under the Cheaper Home Batteries Program (~$372/kWh usable since 1 July 2025) is separate — it does not restore lost solar deeming years.
Eligible CEC-listed panels and inverters, CEC-accredited practitioners, correct paperwork and a system at or under 100kW are non-negotiable for STC creation. DIY electrical work or unaccredited labour voids the pathway. Your DNSP connection approval is separate but must still happen before energisation.
STCs are federal and usually stack with Victoria's Solar Homes solar rebate context, Queensland Battery Booster, SA Home Battery Scheme support and the federal battery discount — subject to each scheme's rules. Income tests and property rules on state programs do not apply to STCs themselves. Have installers show a stacking table: STC solar + state solar (if any) + battery federal/state lines.
A competitive metro 6.6kW price after STC often lands near $5,000–$8,000 depending on roof complexity and hardware. If two quotes show wildly different STC lines for the same size and postcode, one party is mis-estimating zone, deeming year or spot pass-through. Compare three CEC-accredited quotes through MrSolar with identical kW and product tiers.
See STC discounts applied correctly — compare CEC-accredited solar quotes for your postcode on MrSolar.
Written and reviewed by Daniel (Marketplace lead, Epic Unicorn Pty Ltd). We build pages from Australian solar datasets and regulatory references, then map you to CEC-accredited installers only.
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