Sizing, Worked Examples and Quote Checklists
Paying for a home battery: cash, green loans, interest-free offers and state no-interest loans
The ways to pay for a home battery in Australia — cash, green and home loans, interest-free retail finance, WA and ACT loans — with the total cost of each worked out.
The cheapest way to pay for a home battery is usually cash or a low-rate loan you already have, because finance costs come straight off the battery's savings. Next come green loans offered by some banks and lenders for solar and batteries, and state loans where available — the WA Residential Battery Scheme offers no-interest loans of up to $10,000 for households with combined income under $210,000, and the ACT Sustainable Household Scheme offers low-interest loans. "Interest-free" retail finance offered by installers can cost more than it looks, because fees and a higher battery price may be built in. Before you sign, compare the total amount you will pay under each option, not the monthly repayment.
Rates and fees below are illustrative. For payback, see the payback worked example; for quotes, see comparing quotes.
The options compared
| Option | How it works | Good for | Watch out for |
|---|---|---|---|
| Cash | Pay from savings | Lowest total cost | Lost interest on savings |
| Redraw or home loan top-up | Borrow at your mortgage rate | Low rate | Repaid over many years, so total interest can be large if not paid down |
| Green loan (bank or lender) | Personal or secured loan for eligible energy products, sometimes at a discount rate | Fixed term, often lower than standard personal loans | Eligible product lists, establishment fees |
| State no-interest or low-interest loan | Government-backed loans in some states | No or low interest | Eligibility, product lists, VPP conditions in WA |
| Installer "interest-free" plan | Third-party finance arranged at the sale | Convenient | Higher battery price, account fees, late fees, credit checks |
| Buy now pay later | Short-term instalments | Small amounts | Fees, short terms, may not suit large purchases |
The federal Household Energy Upgrades Fund, run through the Clean Energy Finance Corporation (CEFC), has supported discounted green loans through participating lenders. The CEFC does not lend to individuals directly; check its website for current participating lenders.
Worked example: total cost of each option
A battery with a net price of $10,000 after the STC discount. All rates and fees are illustrative.
| Option | Assumptions | Total paid | Extra over cash |
|---|---|---|---|
| Cash | – | $10,000 | $0 |
| Green loan | 6% p.a., 5 years, $250 fee | about $11,850 | about $1,850 |
| Personal loan | 11% p.a., 5 years, $300 fee | about $13,350 | about $3,350 |
| "Interest-free", 5 years | Battery priced $1,200 higher, $3.50 monthly fee | $11,200 + $210 = $11,410 | $1,410 |
| WA no-interest loan | $10,000, 10 years, no interest (eligible WA households) | $10,000 | $0 (but VPP enrolment required) |
How the loans were calculated: a $10,000 loan at 6% over 60 months has a monthly repayment of about $193.33, so 60 × $193.33 = $11,600 plus the $250 fee ≈ $11,850. At 11%, the repayment is about $217.42, so 60 × $217.42 ≈ $13,045 plus the $300 fee ≈ $13,345. Check your own figures with a lender's calculator or Moneysmart's loan calculator.
What finance does to payback
In the payback worked example, the battery saves about $887 a year. The extra cost of finance is effectively added to the net price:
- Cash: $10,000 ÷ $887 ≈ 11.3 years
- Green loan: $11,850 ÷ $887 ≈ 13.4 years
- Personal loan: $13,345 ÷ $887 ≈ 15.0 years
If finance pushes payback well past the warranty term, the battery may not pay for itself.
"Interest-free" offers: what to check
Interest-free does not mean cost-free. The ACCC and state fair trading agencies warn consumers to read finance terms carefully. Check:
- Is the battery price the same with and without finance? Ask for a cash price in writing.
- Account and establishment fees. Monthly fees over five years add up.
- What happens after the interest-free period? Some plans revert to a high rate.
- Late fees and early payout rules.
- Who the credit provider is. It is usually a separate company with its own contract and complaint process.
Credit providers must hold an Australian credit licence. Complaints about a credit provider that you can't resolve directly can go to the Australian Financial Complaints Authority (AFCA).
State loans in detail
| Scheme | Detail (checked October 2026) |
|---|---|
| WA Residential Battery Scheme | No-interest loan up to $10,000, up to 10 years, combined income under $210,000; battery from the supported list; must join your retailer's VPP |
| ACT Sustainable Household Scheme | 3% loans over up to 10 years for eligible products including batteries; $2,000 to $20,000 for new applicants from 1 July 2026 (check current terms on the ACT Government site) |
| Victoria Solar Homes battery loans | Closed to new applications |
See state battery incentives for more.
Finance and door-to-door sales
If a salesperson arranges finance at your door, two contracts are involved: the installation contract (covered by unsolicited consumer agreement rules) and the credit contract. Under the Australian Consumer Law (s 83), if you terminate an unsolicited agreement within the termination period, related contracts and instruments, such as a guarantee or a mortgage or charge in favour of the seller, become void. Credit arranged through a lender linked to the seller (a "tied" loan or continuing credit contract) is excluded from s 83 and dealt with under the National Credit Code instead, so also tell the lender in writing that you have cancelled and ask your fair trading agency or a free financial counsellor if the lender keeps charging you. See door-to-door and phone sales.
FAQ
Is it worth borrowing for a battery?
Only if the saving after finance costs still pays back within a time you're comfortable with, ideally inside the warranty. Use the payback calculator with the total cost of finance as the battery price.
Does the STC discount still apply if I use finance?
Yes. The discount depends on the battery's eligibility, not on how you pay. Make sure the finance amount is calculated on the price after the discount.
Can I use the WA no-interest loan without joining a VPP?
No. The WA Government's scheme page says VPP participation is required for both the rebate and the no-interest loan.
Sources
- Clean Energy Finance Corporation — Household Energy Upgrades Fund and participating lenders
- WA Government — WA Residential Battery Scheme loans
- Moneysmart (ASIC) — loan calculators and credit guidance
- Australian Financial Complaints Authority — complaints about credit providers
- ACCC — consumer rights and unsolicited sales
