Solar Panel Savings Estimator
Estimate your solar panel savings, payback period, and feed-in tariff earnings based on your location and usage in Australia.
6.6kW is the most popular size in Australia
Net cost after STC rebate (typically $3,000–$4,000 off)
Check your electricity bill (kWh per day)
Cost per kWh from your electricity bill
What your retailer pays for exported solar
Portion of solar you use directly (vs. export). 30–50% typical.
How to Use
1. Select your state — solar irradiance varies significantly across Australia 2. Enter system size — 6.6kW is the sweet spot for most homes 3. Enter the net cost after the STC federal rebate (currently ~$3,000–$4,500 for 6.6kW) 4. Enter your daily electricity usage from your bill 5. Enter your tariff and feed-in tariff — check your latest bill 6. Estimate self-consumption — higher if you're home during the day or have a battery2024 Incentives: The STC federal rebate still applies. Some states have additional rebates — check your state government website.
Formula
Daily Generation = Size × Peak Sun Hours × 0.80 | Annual Savings = Self-Consumed × Tariff + Exported × FiTFrequently Asked Questions
What size solar system do I need?
A 6.6kW system is Australia's most popular — it fits on a standard roof and maximises the 5kW inverter (most common grid connection limit). For high users (>25kWh/day), consider 10kW+.
Is a battery worth it?
Currently marginal for most Australians. Batteries add $8,000–$15,000 but the feed-in tariff is low (5–10¢/kWh vs. 25–30¢/kWh you'd otherwise pay). Best suited if you have time-of-use tariffs or go off-grid.
What is the STC rebate?
Small-scale Technology Certificates (STCs) are the federal government rebate applied at point of sale. The value varies by location and system size — a 6.6kW in Sydney typically receives a ~$3,500 discount.
How long do solar panels last?
Quality panels carry 25-year performance warranties. Most degrade at 0.5–0.7% per year, so still produce 85%+ after 25 years. Inverters typically last 10–15 years.
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