Solar Panel Savings Calculator (Australia)
Free solar panel savings calculator for Australian homes. Estimate 25-year lifetime savings using your annual generation, retail rate, state feed-in tariff, self-consumption, and price escalation.
Solar Panel Savings Calculator
Year 1 savings
$1,449
Avg monthly (year 1)
$121
10-year savings
$15,911
25-year lifetime savings
$47,459
Year-by-year savings
| Year | Savings | Cumulative |
|---|---|---|
| 1 | $1,449 | $1,449 |
| 2 | $1,478 | $2,927 |
| 3 | $1,508 | $4,435 |
| 4 | $1,539 | $5,974 |
| 5 | $1,571 | $7,544 |
| 6 | $1,603 | $9,147 |
| 7 | $1,637 | $10,785 |
| 8 | $1,672 | $12,457 |
| 9 | $1,708 | $14,166 |
| 10 | $1,746 | $15,911 |
| 11 | $1,784 | $17,695 |
| 12 | $1,824 | $19,519 |
| 13 | $1,865 | $21,384 |
| 14 | $1,907 | $23,291 |
| 15 | $1,950 | $25,241 |
| 16 | $1,995 | $27,236 |
| 17 | $2,042 | $29,278 |
| 18 | $2,089 | $31,367 |
| 19 | $2,138 | $33,505 |
| 20 | $2,189 | $35,694 |
| 21 | $2,242 | $37,936 |
| 22 | $2,295 | $40,231 |
| 23 | $2,351 | $42,583 |
| 24 | $2,408 | $44,991 |
| 25 | $2,468 | $47,459 |
How to use this calculator
Enter five numbers and the calculator returns year-1 savings, average monthly savings, 10-year savings, and the full 25-year lifetime savings:
- Annual generation (kWh) — output in year 1. CEC-approved retailer quotes include an estimate via the SunWiz or NREL methodology. A 6.6 kW system North-facing produces 9,000-10,500 kWh/year in Brisbane/Sydney, 8,500-9,800 in Melbourne/Adelaide, 7,500-8,800 in Hobart.
- Electricity rate (AUD/kWh) — your usage rate (peak rate for time-of-use customers, single rate otherwise). AER default offer 2026: NSW Endeavour AUD 0.34, VIC AusNet AUD 0.30, QLD Energex AUD 0.32, SA AUD 0.45 (highest in NEM), WA Synergy A1 AUD 0.32, TAS Aurora T31 AUD 0.30.
- Feed-in tariff (AUD/kWh) — what your retailer pays you for exports. See FAQ above for state defaults.
- Self-consumption (%) — share of generation used while it’s produced. Typical for daytime-empty homes: 25-35%. Stay-at-home retirees or work-from-home households: 40-50%. With battery: 65-80%.
- Annual rate escalation (%) — AEMC default-offer trend supports 3-3.5%. Use 4% for NSW/QLD if you’re stress-testing.
How the calculation works
Australian savings split between self-consumed (avoiding the import rate, which escalates) and exported (paid at FiT, typically flat-nominal):
year_n_self_kWh = annual_kWh × (1 - 0.005)^(n-1) × self_pct
year_n_export_kWh = annual_kWh × (1 - 0.005)^(n-1) × (1 - self_pct)
year_n_savings = year_n_self_kWh × import_rate × (1 + escalation)^(n-1)
+ year_n_export_kWh × fit_rate
lifetime_savings = sum of year_n_savings from y = 1 to y = 25Worked example for a Brisbane home with 6.6 kW North-facing on Energex Tariff 11:
- Generation: 9,500 kWh/year
- Import rate: AUD 0.32/kWh
- FiT: AUD 0.085 (Origin Solar Boost first 14 kWh/day)
- Self-consumption: 35%
- Escalation: 3.5%
- Year 1 savings: (9,500 × 0.35 × AUD 0.32) + (9,500 × 0.65 × AUD 0.085) = AUD 1,064 + AUD 525 = AUD 1,589
- Year 25 savings: roughly AUD 3,400
- Lifetime total: roughly AUD 56,000
Lifetime savings by Australian state (2026 reference)
Based on CEC and AER data, 25-year lifetime savings for a typical 6.6 kW North-facing system at 35% self-consumption:
| State / Capital | Annual generation | Year 1 savings | 25-yr lifetime |
|---|---|---|---|
| QLD (Brisbane, Energex + Origin Boost) | 9,500 kWh | AUD 1,589 | AUD 56,000 |
| NSW (Sydney, Endeavour + Solar Boost) | 9,200 kWh | AUD 1,610 | AUD 57,500 |
| VIC (Melbourne, AusNet + AGL) | 8,800 kWh | AUD 1,300 | AUD 47,000 |
| SA (Adelaide, AUD 0.45 retail + Tango FiT) | 9,000 kWh | AUD 1,945 | AUD 67,000 |
| WA (Perth, Synergy DEBS) | 9,800 kWh | AUD 1,520 | AUD 53,000 |
| TAS (Hobart, Aurora T31) | 7,800 kWh | AUD 1,135 | AUD 39,500 |
| NT (Darwin, Jacana) | 9,500 kWh | AUD 1,250 | AUD 43,000 |
| ACT (Canberra, ActewAGL) | 8,500 kWh | AUD 1,355 | AUD 47,500 |
What changes lifetime savings in Australia
Increases savings
- Battery storage — typical 10 kWh battery (Tesla Powerwall 3, Sungrow SBR, BYD HVM) adds AUD 250-AUD 450/year by lifting self-consumption from 35% to 75%. Federal Cheaper Home Batteries Program (effective 1 July 2025) cuts battery upfront cost by 30% via STC-style certificates.
- Premium retailer FiT — switching from a 4¢ default to a 8-10¢ FiT adds AUD 200-AUD 400/year on a 6.6 kW system.
- Time-of-use tariff alignment — match your import to off-peak overnight (AUD 0.18-AUD 0.22) and shift exports to peak window where applicable.
- Daytime electrification — heat-pump hot water (Sanden, Reclaim) and pool heating shift load to solar hours, lifting self-consumption to 50%+.
Decreases savings
- East/West-only roof — produces 10-15% less than North-facing; consider split-string or microinverters.
- Shading from gum trees, neighbouring buildings — partial shading on one panel under string-inverter setups can drop array output 20-25%.
- Demand charges — common on QLD T14 and TAS commercial tariffs — solar reduces kWh but not peak demand.
- Inverter replacement — typical 10-12 year service life means most owners replace once (AUD 1,500-AUD 2,500 for a 5-10 kW string inverter).
Savings vs. payback vs. ROI
- Lifetime savings answers “how much over 25 years?”
- Payback period answers “when do I break even on the AUD 5,000-AUD 9,000 install?”
- ROI / IRR answers “what annualised return versus AusSuper or NAB Term Deposit?”
See our Australian solar payback calculator and solar ROI calculator for the full picture.
Pair this with the payback calculator, ROI calculator, and system cost calculator
Run all four before signing a CEC-approved retailer quote and verify your FiT against your retailer’s energy price fact sheet.
Sources
- Clean Energy Council — approved retailer list, panel/inverter approvals, consumer guides.
- SunWiz Australian Solar Quarterly Reports — install volume and market data.
- AER Default Market Offer reviews — historical and current retail rate caps.
- Clean Energy Regulator (CER) — STC pricing and SRES program rules.
- AEMC Residential Price Trends — forward retail price forecast.
- Solar Choice Price Index — installed AUD/W benchmarks by state.
Frequently asked questions
What is the average 25-year solar saving for an Australian home in 2026?
Clean Energy Council and SunWiz data put 25-year lifetime savings for a typical 6.6 kW residential system at AUD 28,000-AUD 42,000 after the STC discount. A 6.6 kW system in Sydney generates roughly 9,000-10,000 kWh/year, of which 30-40% is self-consumed at the AER default offer (around AUD 0.33/kWh in 2026) and the rest exported at the state feed-in tariff (AUD 0.04-AUD 0.10 depending on retailer and state). Households with batteries, heat-pump hot water, ducted aircon, or daytime EV charging routinely exceed AUD 50,000 lifetime savings by lifting self-consumption to 60-75%.
What feed-in tariff applies in 2026?
Feed-in tariffs are set by retailers (not government, except in WA, NT, and QLD regional). As of mid-2026, leading rates are: NSW (Origin Solar Boost AUD 0.085 first 14 kWh/day), VIC (minimum AUD 0.04 set by Essential Services Commission, premium AUD 0.06-0.10 from AGL/Origin/Energy Locals), QLD (Solar Bonus Scheme closed; new connections AUD 0.04-0.10 retailer choice; Ergon Energy regional AUD 0.083 regulated), SA (AGL AUD 0.06, Tango Energy AUD 0.10), WA (Synergy DEBS AUD 0.10 peak / AUD 0.025 off-peak), TAS (Aurora Energy AUD 0.0888), NT (Jacana AUD 0.0825), ACT (ActewAGL AUD 0.10). Most retailers cap FiT exports at 8-14 kWh/day; check your contract.
How does the STC rebate fit in?
The Small-scale Renewable Energy Scheme (SRES) issues Small-scale Technology Certificates (STCs) at installation. STC value AUD 36-39 in mid-2026 (CER spot price), and a 6.6 kW system in Zone 3 (most of NSW, VIC, SA) earns roughly 80-90 STCs — about AUD 2,900-3,500 off the install price. STCs are one-off, paid up-front via your installer (point-of-sale discount), so they don't affect the year-over-year savings stream. The scheme is scheduled to phase out by 2030 (deeming period reduces 1 year each year).
What rate escalation should I assume in Australia?
AER and AEMC default offer reviews show retail electricity prices rose 4-7%/year average over the last 10 years on the NEM (NSW, VIC, QLD, SA, TAS, ACT). The 2026-2030 forward outlook from AEMC's Residential Price Trends report projects 2-4%/year nominal as transmission expansions (HumeLink, EnergyConnect, VNI West, Project EnergyConnect) come online. WA SWIS and NT have lower escalation due to gas-dominated supply. Use 3-3.5% as a realistic forecast, 4% if you're in NSW/QLD where coal closures are accelerating.
Are feed-in tariff payments taxable?
For households running solar non-commercially, no. The ATO's TR 2003/D8 and subsequent guidance treat FiT receipts to domestic premises as not constituting an enterprise — outside the scope of GST and Income Tax. Energy savings (offset of your bill) are also non-taxable. Larger commercial systems above 100 kW or with >$75,000 GST turnover trigger different treatment; consult your accountant.