Most households that buy a home battery in 2026 do not pay for it from savings. They borrow part of it, or all of it, and the quote they signed does not always make clear what that borrowing costs. The federal Cheaper Home Batteries Program has taken a large slice off the price, which makes the loan smaller than it would have been a year ago. It does not make the loan free.
This guide sets out the finance options in plain terms, shows the repayment arithmetic on a realistic rebate-reduced price, and flags the points where the quote and the loan contract are most likely to disagree. It is general information, not financial advice, and the interest rates below are illustrations, not offers.
Start with the net price
Before comparing finance, work out how much you actually need to borrow. The program creates small-scale technology certificates (STCs) for batteries between 5 kWh and 100 kWh usable, with up to 50 kWh counted. The count is usable kWh multiplied by the program factor, which is 6.8 at the time of writing, stepping down to 5.7 on 1 January 2027 and 5.2 on 1 July 2027. Since 1 May 2026 the first 14 kWh earn at 100% of the factor, 14 to 28 kWh at 60% and 28 to 50 kWh at 15%.
Take a 13.8 kWh usable battery. That is 13.8 x 6.8 = 93.8, rounded down to 93 STCs. At the STC spot range of roughly $38 to $40 that is about $3,534 to $3,720. Your installer normally takes the certificates and shows the value as a discount on the invoice, so you borrow against the net figure. Use the battery STC calculator to run your own battery size, and read how the rebate is calculated for the tier arithmetic.
If you delay until the January 2027 step, the same battery earns 13.8 x 5.7 = 78 STCs, roughly $570 less at $38. That is a reason to settle your finance early, not a reason to rush a loan you have not compared.
The main finance options
Green or secured loans
Several banks and lenders offer reduced-rate loans for solar and battery purchases, often secured against a car or the property. Secured loans usually carry the lowest interest rates because the lender has recourse to the asset. The trade-off is that you are putting a car or home behind a battery. Ask for the comparison rate, which includes fees, rather than the headline rate.
Unsecured personal loans
An unsecured personal loan is simple and quick, with a fixed term and fixed repayments. Rates are higher than secured loans, and a lender may charge an establishment fee and an early-repayment fee. It suits a borrower who wants no link between the loan and the property.
Installer-arranged finance
Many installers partner with a finance provider and offer a one-page application at the quote stage. It is convenient, and sometimes the rate is competitive. The risks are fees buried in the contract, a rate that depends on the installer’s commission arrangement, and a loan that is signed before the install is complete. Take the contract home and compare it against one outside offer.
Mortgage top-up, redraw or offset
If you have a home loan with available redraw, using it costs the mortgage rate, usually the cheapest money available. The risk is the term: a battery paid off over 25 years costs far more in interest than one paid off over five. If you use redraw, set a personal target repayment so the battery does not quietly become a 25-year debt.
Interest-free and buy-now-pay-later offers
Some retailers advertise interest-free periods. They can work if you will certainly clear the balance inside the window. If you miss it, deferred interest and fees can apply from day one. Read the contract, not the banner.
Government loans
Several state schemes have closed: the Victoria Solar Battery Loan, the Tasmanian Energy Saver Loan, the Queensland Battery Booster and the Northern Territory battery scheme. The WA battery scheme is active and requires VPP participation. Check your state energy department’s page, because availability changes and an old article may still show a scheme as open.
What the repayments look like
Suppose the net price after STCs is $9,000 and you borrow all of it. These are illustrative repayments, not quotes.
| Loan | Monthly repayment | Total interest |
|---|---|---|
| $9,000, 5 years at 8% | about $182 | about $1,949 |
| $9,000, 5 years at 12% | about $200 | about $3,012 |
| $9,000, 7 years at 8% | about $140 | about $2,781 |
Two lessons come out of the table. A four-point rate difference costs about $1,060 over five years, so shopping around is worth an hour. And stretching to seven years drops the monthly figure by $42 but adds more than $800 of interest compared with five years at the same rate.
Does the battery pay its own repayments?
Compare the repayment with the saving. Assume the battery shifts 9 kWh a day from the evening peak. If your import rate is 35 cents and your solar export is paid 5 cents, each shifted kWh is worth about 30 cents. That is $2.70 a day, or about $985 a year. The 5-year repayment at 8% is about $2,190 a year.
On those numbers the battery does not pay its own loan from bill savings alone, and that is before you consider its life, which is typically longer than a five-year loan. Savings from a VPP sign-up, backup power value and protection against future tariff rises are real, but they are personal. Do the sum with your own tariff and your own usage, and treat the result as the true test of whether a loan is sensible.
From the desk: the most common finance mistake we see is a loan written on the gross price, with the STC discount “applied later”. If the certificate claim is delayed or rejected, the borrower is left carrying the gap. Ask the installer in writing: is the STC discount already on the invoice, and what happens to my price if the claim fails?
Questions to ask before you sign
- What is the comparison rate, and is it fixed or variable?
- Are there establishment, monthly or early-repayment fees?
- Is the loan amount the net price after the STC discount?
- Does the loan contract link to the installer, so a dispute with the installer affects my repayments?
- Does the battery model qualify for the program, with a CEC-approved battery, VPP capability and an accredited installer? The eligibility answer explains the list.
A note for installers offering finance
If you put finance in front of customers, quote the net price and the finance line separately, and keep your certificate cash flow independent of the customer’s loan approval. The slowest part of a battery job is usually waiting on the claim, not the customer. We cover the paperwork side in the installer guide to the program and the claim steps on the battery STCs page, and the how it works page shows when a rate is locked and when you are paid.
What to do next
- Work out your battery’s STC count and net price with the battery STC calculator.
- Get at least one finance offer from outside your installer and compare comparison rates.
- Run the savings sum with your own tariff before choosing a term.
- Read how much a battery costs after the rebate for the cost side.
- If you sell batteries, see our pricing page for the published certificate rate.