TL;DR
- STC: ~$3,800-$4,200 off a 10 kW system in Mackay (Zone 3). Upfront, point-of-sale.
- Federal Battery Booster: up to 30% off installed battery cost.
- QLD Battery Booster: means-tested state top-up, stacks with federal.
- Combined, eligible households save 35-45% on battery capex.
STC — the rebate you never see
Small-scale Technology Certificates (STC) are the federal solar rebate. Retailers quote "after STC" pricing because the certificates are assigned to the installer in exchange for the upfront discount. Three things drive STC value:
- Zone: Mackay is Zone 3 (the second-best zone for STC generation).
- Deeming period: years between install and scheme end (2030). In 2026 it's 4 years. In 2027 it's 3, etc.
- Certificate price: market-driven, currently ~$38-$40 per STC.
Federal Battery Booster (launched 2025)
Up to 30% off installed battery cost, capped by usable capacity. Eligibility requires:
- CEC-accredited installer (we are).
- Battery on the CEC approved list.
- Battery size between 5 kWh and 50 kWh usable.
- Paired with new or existing solar.
QLD Battery Booster (state)
Means-tested rebate that stacks with the federal scheme. Current caps and income thresholds are published on the QLD Department of Energy and Public Works site. Typical outcome: an additional $1,000-$3,000 for eligible households.
What doesn't exist (anymore)
- QLD state solar panel rebate — discontinued years ago.
- Feed-in tariff subsidy — QLD's mandatory feed-in ended in 2017. Retailers now set voluntary rates (8-12c/kWh in Mackay).
- Interest-free state loans — some schemes closed in 2024. Green loans from accredited providers remain.
Stacking example — 10 kW + 10 kWh
| Component | Gross cost | Rebate | Net cost |
|---|---|---|---|
| 10 kW solar | $13,000 | -$4,100 STC | $8,900 |
| 10 kWh battery | $13,000 | -$3,900 Federal BB + $1,500 QLD BB | $7,600 |
| Combined | $26,000 | -$9,500 | $16,500 |
FAQs
Do I need to apply for the rebates myself?
No. We handle STC and Battery Booster paperwork. You sign the assignment form, we do the rest. Approvals generally take 2-6 weeks post-install.
Can I backdate a rebate on a recently installed system?
Not usually. Rebates are tied to install commissioning date and must be applied through the original retailer/installer. Always confirm eligibility before you sign a contract.
Want a rebate-adjusted quote?
Free design — we calculate your actual STC + Battery Booster eligibility.
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