How to check a home battery quote: 10 red flags (Australia, 2026)

Updated 17 October 2026 · General information only, not personal financial or electrical advice.

About 276,000 home batteries went in across Australia in the first half of 2026 (Clean Energy Council). The rebate rules changed partly to curb the over-selling of large batteries (ABC News). Here's what to check before you sign.

Ten red flags

Only nominal kWh is shown. Rebates and real-world performance depend on usable kWh (CER).
The battery is far bigger than your evening use. Above 28 kWh, each extra kWh earns only 15% of the rebate rate.
Your solar can't fill it. If your spare daytime solar is well below the battery size, it will rarely charge fully.
The rebate isn't itemised. Ask for the STC count, the price per STC, and the factor used for your install date.
"Rebate ends tomorrow" pressure. Step-downs are published well in advance. The next one is 1 January 2027 (6.8 → 5.7 STCs/kWh).
Savings claims with no assumptions. Ask which tariff, feed-in rate and usage figures were used.
No look at your actual usage. A good designer asks for your interval data or at least a year of bills.
Vague backup claims. Is it whole-home or essential circuits only? Is the backup gateway included in the price?
Warranty with no throughput limit. Check the years, the MWh cap and the capacity retained at the end of the warranty.
No accreditation or licence details. Ask for the installer's accreditation, the retailer's approved-seller status and the electrician's licence number, then verify them.

Your consumer rights

Door-to-door and phone sales: if the deal was unsolicited, you generally get a 10-business-day cooling-off period (ACCC; Amir to confirm the cooling-off detail).
Consumer guarantees: these apply whatever the contract says (ACCC).

Compare quotes like for like

Work out the net price per usable kWh for each quote: price after rebate ÷ usable kWh. Then compare the warranty and installation scope side by side.

Get the full checklist. SortedDIY Mid (A$99) includes your automated report plus the Kit: the 25-point "Check Your Quote" PDF and the calculator. Want a licensed electrician to read your quotes? Choose SortedDIY Pro (A$349).

General information only. This is not personal financial or electrical advice. Get advice from a licensed, accredited installer.