floor(6.8 × tiered usable kWh) × $39.90
- 100% of the first 14 usable kWh counts
- 60% of capacity from 14 to 28 kWh
- 15% of capacity from 28 to 50 kWh, nothing above
13.5 kWh usable → 91 STCs
$3,631
Verified against DCCEEW + all 8 states · 13 July 2026
Battery rebate calculator
Every federal and state rebate for your postcode, stacked and sourced. The answer is free and instant, no email needed.
Rebates are set by state + network
$500/quarter
≈ $2,000 a year
Your place
Type your postcode and your number appears here. Federal battery discount, solar STCs, state extras, all stacked, all sourced. Nothing gated.
Federal battery discount · Solar STCs · State programs · Every figure sourced and dated
01 · The formulas
How this calculator works
No black box. These are the two federal formulas the calculator runs, straight from the legislation, plus the state programs it stacks on top.
floor(kW × zone rating × 5) × $39.90
- 5 deeming years for a 2026 install, drops by one every 1 January
- Zone rating set by your postcode, see the table below
- Scheme ends 31 December 2030
6.6 kW in Sydney → 45 STCs $1,796
The four STC zones (solar)
| Zone | Rating | Example cities | 6.6 kW rebate |
|---|---|---|---|
| Zone 1 | 1.622 | Darwin, far north WA + QLD | $2,115 |
| Zone 2 | 1.536 | Alice Springs, outback QLD | $1,995 |
| Zone 3 | 1.382 | Sydney, Brisbane, Adelaide, Perth | $1,796 |
| Zone 4 | 1.185 | Melbourne, Canberra | $1,556 |
Hobart uses a 1.092 rating. Full zone detail on the STC rebate explainer.
What stacks on top, by state
- NSW VPP connection incentive (PDRS) up to $1,500
- VIC Solar Homes panel rebate (solar only) $1,400
- WA Residential Battery Scheme, $130/kWh (Synergy) capped at $1,300
- SA REPS VPP incentive priority group only in 2026
Everywhere else the federal programs still apply in full. State detail lives on the rebates hub.
02 · Quote check
Check your quote against the current rates
Every row computed from the current 6.8 STCs/kWh factor and the $39.90 spot price. If your quote's battery discount is far off these numbers, ask why.
| Battery (usable) | STCs | Gross at the $40 cap | Typical net on invoice |
|---|---|---|---|
| 10 kWh | 68 | $2,720 | $2,440–$2,520 |
| 13.5 kWh | 91 | $3,640 | $3,294–$3,402 |
| 16 kWh | 103 | $4,120 | $3,709–$3,830 |
| 20 kWh | 119 | $4,760 | $4,294–$4,435 |
| 27 kWh | 148 | $5,920 | $5,319–$5,494 |
Net assumes the typical installer pass-through of $244–$252 per counted kWh after admin fees. Program detail on the Cheaper Home Batteries explainer.
03 · The step-down schedule
The battery factor is on a legislated clock
Locked in law, not a sales tactic. Here is every scheduled step-down and what each one does to the rebate on a 13.5 kWh battery.
| Certification period | Factor (STCs/kWh) | Rebate on 13.5 kWh |
|---|---|---|
| 1 Jan 2026 to 30 Apr 2026 | 8.4 | $4,509 |
| 1 May 2026 to 31 Dec 2026 now | 6.8 | $3,631 |
| 1 Jan 2027 to 30 Jun 2027 | 5.7 | $3,032 |
| 1 Jul 2027 to 31 Dec 2027 | 5.2 | $2,793 |
| 1 Jan 2028 to 30 Jun 2028 | 4.6 | $2,474 |
| 1 Jul 2028 to 31 Dec 2028 | 4.1 | $2,195 |
| 1 Jan 2029 to 30 Jun 2029 | 3.6 | $1,915 |
| 1 Jul 2029 to 31 Dec 2029 | 3.1 | $1,636 |
| 1 Jan 2030 to 30 Jun 2030 | 2.6 | $1,397 |
| 1 Jul 2030 to 31 Dec 2030 | 2.1 | $1,117 |
Source: DCCEEW, Cheaper Home Batteries Program. Verified 13 July 2026.
04 · Common questions
Battery rebate questions, answered with the formula
How is the battery rebate calculated in 2026?
STCs earned × the STC price. A battery earns 6.8 STCs per usable kWh, with capacity counted at 100% for the first 14 kWh, 60% from 14 to 28 kWh and 15% from 28 to 50 kWh, then rounded down to a whole certificate. At the current $39.90 spot price, a 13.5 kWh battery earns 91 STCs, about $3,631 gross before installer admin fees.
What is the rebate for a 10 kWh battery?
A 10 kWh (usable) battery earns 68 STCs: 6.8 × 10, rounded down. At the current $39.90 spot price that is about $2,713 gross. After typical installer admin fees, expect a net discount of roughly $2,440 to $2,520 on the invoice, plus any state incentive that stacks on top.
Does the calculator include state rebates?
Yes. It stacks the federal battery discount and solar STCs with the live state programs for your postcode: the NSW VPP connection incentive (up to $1,500), the WA Residential Battery Scheme ($130 per usable kWh, capped at $1,300 for Synergy customers), and Victoria's $1,400 Solar Homes panel rebate. It also flags SA's REPS incentive as priority-group-only for the rest of 2026. Closed programs are excluded, so the total is what you can actually claim today.
Why is my installer's number different?
Usually one of three reasons. Gross versus net: we show the gross STC value at the $39.90 spot price, while installers pass through a net figure after admin fees, typically $244 to $252 per kWh on the first 14 kWh. Usable versus nominal capacity: a "13.5 kWh" battery is rebated on its usable capacity, which can be lower than the nameplate number. Or the quote was priced on an old factor or a stale STC price. If the gap is more than about 10%, ask the installer to show the STC line item and the date it was calculated.
When do the rates drop next?
On 1 January 2027, when the battery factor steps down from 6.8 to 5.7 STCs per kWh. On a 13.5 kWh battery that is $599 less rebate for exactly the same install. The schedule is legislated and keeps stepping down every 1 January and 1 July until the program ends in December 2030. The solar STC deeming period also drops by one year every 1 January.