How the Cheaper Home Batteries Program works

The Cheaper Home Batteries Program does not send you a cheque. It knocks money off the price of an eligible battery by creating small-scale technology certificates (STCs) for that battery. Your installer, or the trader they sell to, collects the certificates and sells them, and the value shows up as a lower invoice. At launch on 1 July 2025 that discount was roughly 30 per cent of the cost of a typical system.

That one sentence explains most of what confuses people. The discount is a number of certificates multiplied by a price, both of which can move. Here is how the pieces fit, with a worked example.

The four steps

1. You buy an eligible battery. It must be on the approved list, between 5 and 100 kWh usable, and able to connect to a virtual power plant (VPP). See who and what qualifies.
2. An accredited installer fits it. The installer records the model, serial numbers, usable capacity, photos and compliance paperwork.
3. The battery creates STCs. The number depends on usable kWh, the STC factor for the installation date, and the size bands that have applied since 1 May 2026.
4. The certificates are assigned and sold. You sign an assignment form handing the STCs to the installer or their trader. The value has already come off your invoice.

You never deal with the certificates yourself unless you choose to. The assignment form is what transfers ownership, and it is the document that makes the upfront discount possible.

Where the discount number comes from

For each battery the program calculates certificates like this:

• Take the usable capacity in kWh, up to 50 kWh.
• Apply the STC factor for the installation year. At the time of writing it is 6.8 for installs from 1 May 2026, stepping down to 5.7 on 1 January 2027 and 5.2 on 1 July 2027 (the factor now steps every six months to 2030), and it keeps stepping down to 2030.
• Apply the size bands: the first 14 kWh at the full factor, 14 to 28 kWh at 60 per cent, and 28 to 50 kWh at 15 per cent.
• Multiply the resulting certificates by the going price of an STC. The spot market has been roughly $38 to $40, with the clearing house ceiling at $40.

Worked example: a 10 kWh battery

Ten kWh is under the 14 kWh band, so the full factor applies.

Same battery, same house, and roughly $400 difference purely because of the date. That gap is why the timing question comes up so often; we look at it in should you buy a battery before 2027.

A bigger battery

A 20 kWh battery gets the full factor on the first 14 kWh and 60 per cent on the next 6. At a factor of 6.8 that is 95.2 certificates plus 24.5, or about 119.7. The extra 6 kWh adds only about a quarter of what the first 6 kWh did. Larger batteries still make sense for some households, but the discount per extra kWh drops quickly.

What it looks like on your quote

A clear quote lists the battery price, then a separate line for the STC discount, then the amount you pay. If a quote just gives you a single price and says “rebate included”, ask for the breakdown. You want to see:

• the usable capacity used in the calculation
• the number of STCs
• the dollar value assigned to each
• the planned installation date

Installers carry the certificate value on their books until the trader pays, so a quote that is oddly generous may be built on a certificate price the installer cannot actually get. Sensible installers use a conservative price.

What the program does not do

• It does not require you to join a VPP, though it requires the battery to be capable of it.
• It is not means-tested.
• It does not cover more than one battery per property.
• It does not guarantee a fixed dollar discount. The market price of STCs sets the final figure.

Whether you can also claim a state incentive is a separate question, which depends on where you live. We cover it in can you stack battery rebates.

What happens behind the scenes

After installation, the installer prepares the claim: photos, serial numbers, the signed assignment form, and the compliance documents. The claim is lodged with the Clean Energy Regulator (CER), validated, and the certificates are created and sold. A good trader reviews the claim before lodgement so errors are fixed early. If you want to see what that paperwork looks like, the battery submission guide goes through it.

A second worked example: why the date matters

Take a household that signs on 20 November for a 14 kWh battery with usable capacity of 13.1 kWh. If it is installed on 10 December, the factor is 6.8, so 13.1 x 6.8 = 89.08, about 89 STCs, or roughly $3,382 at $38. If supply delays push the install to 12 January, the factor is 5.7 and the result is 74.67, about 74 STCs, roughly $2,812. The difference is about $570 for the same battery and the same contract. Nothing about the household changed. Only the calendar did.

That is why we suggest two things. Ask for the installation date in writing, and ask the installer how the price changes if the date moves across a step. A fair contract either fixes the price or says plainly how it adjusts.

What happens if you change your mind

Because the discount is applied through certificates assigned at installation, it is hard to unwind later. Decide on size and product before you sign the assignment form. If your needs change before installation, tell the installer immediately, as the certificate count depends on the final usable capacity actually installed, not the figure on the original quote.

What to do next

• Get two or three quotes that show usable kWh, STC count and the dollar value separately.
• Check the installer’s accreditation and the battery’s place on the approved list.
• Confirm the installation date and what happens if it moves.
• Read the battery STC overview for the full picture, or the installer guide if you want the detail from the other side of the quote.

If you are an installer wondering how quickly the discount you carry comes back to you, see how long STC payment should take or check today’s rates on the pricing page.