Estimate the dollar value of the federal battery discount from your battery's effective usable kWh, the STC factor for the installation period and a range of STC prices.
This estimator turns the Clean Energy Regulator's STC factor into an approximate dollar discount for a home battery under the Cheaper Home Batteries Program.
Formula. Certificates ≈ effective usable kWh × STC factor for the installation period. Discount ≈ certificates × STC price. The tool multiplies your effective kWh by a per-kWh range (factor × a lower and a higher STC price) and adds any state or VPP incentive you type in.
Effective kWh (the tier rule from 1 May 2026). Count the first 14 kWh of usable capacity in full, each kWh above 14 up to 28 kWh at 60%, and each kWh above 28 up to 50 kWh at 15%. Capacity above 50 kWh earns nothing. For example, a 20 kWh battery is 14 + 6 × 0.6 = 17.6 effective kWh; a 32 kWh battery is 14 + 14 × 0.6 + 4 × 0.15 = 23 effective kWh.
Worked example (illustrative). A 13.5 kWh usable battery installed in November 2026: 13.5 × 6.8 = about 91 certificates. At $33–$38 per certificate that is roughly $3,029–$3,488. The CER's rooftop solar page describes the usual certificate price as about $33–$38 but does not set it; your agent's price may differ and may be net of fees.
Limits. The installation date, not the contract date, decides the factor. Certificates are whole numbers and the CER's own STC calculator gives the exact count. The tool does not check eligibility (CEC-listed battery, VPP-capable, accredited installer, one battery per NMI). See how the STC factor works and the 2026 rebate overview.
Battery Costs, Rebates and 2026 Rules
How the battery STC factor works after 1 May 2026 — the six-monthly step-downs to 2030, the 14, 28 and 50 kWh tiers, worked examples and why the install date matters.
Battery Costs, Rebates and 2026 Rules
The 2026 home battery rebate explained — Cheaper Home Batteries Program STC factors after 1 May 2026, size tiers, eligibility, state incentives and how to check a quote.
Battery Costs, Rebates and 2026 Rules
Which state and territory battery incentives are open in October 2026 — the NSW VPP incentive, WA Residential Battery Scheme, Victorian loans, ACT loans — and how they stack with the federal discount.
