Gridly
Battery Cost Savings Calculator
Calculate the annual dollar savings, payback period and 10-year net return for a home battery system in Australia - including state rebates and feed-in tariff impact.
Total supply + installation cost before rebate
VIC: up to $8,800 · SA: loan · ACT: up to $15,000 · QLD: $3,000
Use the Energy Savings Calculator to get this figure
Your peak/shoulder rate - check your electricity bill
Rate your retailer pays for exported solar (often 2–7¢)
Typical LFP: 1–3%/yr. Capacity reduces slightly each year.
Your Results
Annual saving (year 1)
$960
vs exporting to grid at FiT
Payback period
10.4 yrs
after rebate deducted
10-year net saving
-
after system cost
Net cost after rebate
$10,000
Arbitrage value / kWh
25¢
10-yr cumulative saving
-
Return on investment
-%
Calculator notes
- Annual saving = kWh avoided × (grid rate − FiT). This is the true arbitrage value: the difference between what you'd pay vs. what you'd earn by exporting.
- Payback = net cost ÷ year-1 saving. Actual payback may be faster if electricity prices rise.
- Degradation reduces kWh output each year. 10-year figures account for this compounding effect.
- Does not include VPP income, time-of-use arbitrage, or blackout protection value - all of which can improve returns.
- Get your "Annual grid energy avoided" from the Battery Energy Savings Calculator.