Solar + battery savings calculator
Answer four questions and get an honest estimate — system size, cost after rebates, annual savings and payback. Every figure we use is listed below in Our assumptions.
Your estimate
Our assumptions
- State tariffs (2026–27 regulated benchmarks): NSW 34.0c/kWh, VIC 29.0c/kWh, QLD 28.5c/kWh, SA 41.9c/kWh, WA 33.3c/kWh. Conservative flat feed-in tariffs: NSW 4c, VIC 3c, QLD 4c, SA 3c, WA 2.5c, TAS 8c, ACT 6c, NT 8c.
- Solar installed cost: $1,000/kW — price already includes the STC discount ($38/STC, 5-year deeming in 2026).
- Battery installed cost: $1,100/kWh before the federal rebate of ~$245/kWh on the first 14 kWh usable (60% rate for 14–28 kWh, 15% for 28–50 kWh; Cheaper Home Batteries Program, May–Dec 2026).
- Average yield 3.9 kWh per kW per day (estimate; varies 3.4–4.3 by zone). Roof orientation factors are typical estimates: N 1.0, NE/NW 0.95, E/W 0.85, S 0.7.
- Self-consumption: 35% solar-only, 65% with battery — industry-typical estimates, not measured data.
- Electricity price rises and panel degradation assumed 0 (conservative baseline).
Enter your details above to see the assumptions tailored to your state.
General information only — not financial, investment or product advice. Figures are estimates based on published averages; get installer quotes for your situation.