Federal Battery Rebate Calculator
This battery rebate calculator works out your discount under the federal Cheaper Home Batteries Program. Pick the models we install, or add several if you are stacking units, and the calculator applies the current certificate rate to your total usable capacity.
Cheaper Home Batteries Program — discount by usable capacity.
Step 1 · Your battery
Why usable capacity, not the number on the box?
Batteries are often sold at nominal capacity, but most lithium systems cannot be discharged fully without shortening their life. Usable capacity is what the manufacturer warrants you can actually draw, and it is the figure the rebate is calculated on.
The gap varies by brand. FoxESS EQ4800 runs at 100% depth of discharge, so nominal and usable match. A Sofar PowerAll module rated 5.12 kWh gives 4.75 kWh usable. Using the wrong figure overstates the rebate by several hundred dollars.
Why would I add more than one battery?
Most of these systems are modular. Two FoxESS towers, or a Pylontech rack of six units, are treated as one system and the rebate is calculated on the combined usable capacity.
That matters because the rate tapers above 14 kWh. Stacking pushes some of your capacity into a lower band, so the second half of a large system earns considerably less than the first.
Some single units are too small to qualify
The program has a 5 kWh minimum on usable capacity. A single Pylontech US5000 at 4.56 kWh or a single Sofar module at 4.75 kWh falls below that on its own, so at least two units are needed before any certificates are created.
Step 2 · When it gets installed
Why the install date matters
The rebate is set by the certificate rate applying on the day your battery is installed, not the day you sign the contract. The rate stepped down on 1 May 2026 from 8.4 to 6.8 certificates per kWh, and it now steps down roughly every six months through to 2030.
An install that slips past a step-down date earns less. If you are ordering close to a change, ask for the installation date in writing.
How the battery rebate works
The Cheaper Home Batteries Program started in July 2025 and delivers roughly 30% off the upfront cost of an eligible battery. It runs through the same certificate system as solar — your installer creates small-scale technology certificates based on the battery's usable capacity, sells them, and passes the value on as a discount before you pay.
What changed on 1 May 2026 is how many certificates each kilowatt hour earns. The flat rate became a tapered one, and the underlying factor dropped from 8.4 to 6.8 certificates per kWh.
The first 14 kWh is where the money is
Under the tapered structure, capacity beyond 14 kWh earns 60% of the rate, and beyond 28 kWh only 15%. Oversizing a battery no longer buys you a proportionally bigger rebate. Size it to your evening usage instead — that is where the return actually comes from.
Worked examples from systems we install
Calculated at 6.8 certificates per kWh with a certificate value of $37, using manufacturer usable capacity figures.
What changes your number
Usable capacity
The rebate is based on usable capacity, not nominal. The gap varies by brand — some run 100% depth of discharge, others closer to 90%.
Install date
The rate on the day your battery is installed is the one that applies. It steps down again on 1 January 2027.
System size
Systems must be between 5 kWh and 100 kWh to qualify. Certificates are only created on the first 50 kWh.
Certificate price
Certificates trade on an open market. The value here uses $37, which is what installers typically net after fees.
Installer accreditation
The battery must be installed by a CEC-accredited installer using approved equipment, otherwise no certificates are created.
Solar pairing
The battery can be added to new or existing solar, so a retrofit onto panels you already own still qualifies.
Victorian households: federal only
Victoria has no active state battery rebate. The Solar Homes battery rebate and its interest-free loan both closed in late 2024, so Victorian households now access the federal program alone. Any quote or article still quoting Solar Homes battery figures is out of date.
The federal discount does stack with the solar STC rebate if you are installing panels and storage together, since the two are calculated separately.
Frequently asked questions
Eligibility, timing, tapering and how the discount reaches you.
How much is the federal battery rebate?
Around 30% off the upfront cost. In dollar terms it works out near $252 per kWh on the first 14 kWh of usable capacity, so a 13.98 kWh FoxESS EQ4800-L3 earns roughly $3,515. Capacity above 14 kWh earns less per kilowatt hour under the tapered structure introduced in May 2026.
Do I claim the battery rebate myself?
No. It is claimed at the point of sale. Your installer creates and lodges the certificates with the Clean Energy Regulator and deducts the value from your price. You pay the already-discounted figure and never chase a rebate afterwards.
What is the minimum battery size for the rebate?
Five kilowatt hours of usable capacity. Some single modules fall below that on their own — a Pylontech US5000 at 4.56 kWh usable, or a single Sofar PowerAll module at 4.75 kWh — so at least two units are needed before any certificates are created.
Can I add a battery to solar I already have?
Yes. The rebate covers a new eligible battery paired with new or existing solar, so a retrofit onto panels you already own qualifies. The battery needs to be between 5 kWh and 100 kWh and installed by a CEC-accredited team.
Is a bigger battery still worth it?
For the rebate alone, no. Capacity beyond 14 kWh earns 60% of the rate and beyond 28 kWh only 15%, so the discount does not scale proportionally. Size the battery to your evening usage rather than chasing capacity, which is what our battery sizing calculator helps with.
Is there a Victorian state battery rebate?
No. The Solar Homes battery rebate and its interest-free loan both closed in late 2024. Victorian households access the federal Cheaper Home Batteries Program only. Ignore any quote still citing Solar Homes battery figures.
When does the rate drop again?
The next step-down is 1 January 2027, and the factor is reviewed at least annually through to 2030. The rate applying on your installation date is the one you get, so an install that slips past a step-down date earns less.
We confirm usable capacity, check the rate applying on your install date, and deduct it from your fixed installed price.
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