The solar rebate drops on 1 January 2027: should your business install now or wait?

The solar rebate isn’t a cheque. It’s a discount on the installer’s quote, worked out from certificates the system is entitled to create. Two things set the number of certificates: the size of the system and the year it’s installed. On 1 January 2027, that second input moves against you.

This guide is for owners who already have solar or a battery on the list for the next year and want to know whether the step-down is worth bringing the job forward.

What exactly changes on 1 January 2027?

Two separate discounts step down on the same day.

Rooftop solar. Under the Small-scale Renewable Energy Scheme, a system creates certificates up front for the electricity it’s expected to generate over a “deeming period”. The Clean Energy Regulator’s table puts that period at 5 years for systems installed in 2026 and 4 years for 2027, and it “decreases by one year each year until 2030 when the scheme ends”. (CER)

Going from five years to four means about 20% fewer certificates for an identical system.

Batteries. Since the Cheaper Home Batteries changes of 1 May 2026, the battery factor falls every six months instead of once a year:

Battery installed	Certificates per kWh
1 May – 31 December 2026	6.8
1 January – 30 June 2027	5.7
1 July – 31 December 2027	5.2
1 January – 30 June 2028	4.6

Source: CER

The battery discount also tapers with size. The first 14 kWh earns the full factor, each kWh from 14 to 28 earns 60%, and each kWh from 28 to 50 earns 15%. (CER)

Does my business qualify for the battery discount?

Probably, if the battery is the right size. business.gov.au lists the Cheaper Home Batteries Program as open to “Australian households, businesses and community organisations”. The battery must be 5 kWh to 100 kWh and connected to a new or existing solar system. (business.gov.au) Certificates are only created on the first 50 kWh of usable capacity, so a bigger bank gets no extra discount on the rest.

For solar, small-scale means no more than 100 kW of capacity and under 250 MWh of output a year. Above that, the CER treats the system as a power station under the large-scale scheme. (CER) If you’re designing a 150 kW system for a cold store, the January deadline isn’t really your problem.

Which date counts: the contract, the invoice or the install?

The install. That’s the trap. When the battery factor dropped in May, the Clean Energy Regulator said plainly that rebates depend on the installation date, “not the date the contract is signed”. It also told retailers to only promise installs before the change if they were certain they could finish on time. (CER) The solar deeming period works the same way, by installation year.

So a quote signed on 15 December means nothing if the crew can’t get on your roof until 8 January. The quote will be reissued at the lower discount, and it’s the installer’s right to do that if the contract says the price depends on the certificate value at installation. Read that clause before you sign.

How much time do I really have?

About ten weeks from today, and the last two disappear quickly. Work back from 31 December:

1. Mid to late December. Most installers wind down for Christmas. Assume nothing gets installed after about 19 December.
2. Late November to early December. Panels, inverter and battery need to be in stock. Ask for the brands that are on the shelf, not on a ship.
3. November. Grid connection approval from your network. Larger commercial systems can need longer, sometimes with export limits.
4. Now to early November. Quotes in, roof checked, the funding sorted and the contract signed.

If your installer can’t confirm a date with a straight face, plan on the 2027 rate and pick your timing on the other merits. Our supplier lead times page covers how to get deposits and order dates working for you.

Illustrative example: the bakery with a December window

Illustrative only. Invented business and figures.

A bakery runs ovens, coolrooms and display fridges from 4am. The owner has a quote for a 30 kW solar system and a 20 kWh battery. They’re choosing between a 10 December install and a late-February install after the Christmas rush.

To keep the maths simple, assume an illustrative zone rating of 1.382 (the multiplier for the business’s location), a certificate value of $38 and bill savings of $850 a month once the system is running.

	Installed December 2026	Installed February 2027
Solar certificates (30 × 1.382 × deeming years)	207	165
Battery certificates (14 kWh full, 6 kWh at 60%)	119	100
Total certificates	326	265
Discount at $38 each	$12,388	$10,070

The later install loses $2,318 of discount. It also gives up about three months of savings, around $2,550. The cost of waiting is roughly $4,870, and that’s before any price change on the hardware.

Now the other side of the ledger. The owner would borrow to cover the out-of-pocket cost either way, so bringing the install forward adds only about three months of finance cost. That’s a few hundred dollars, against nearly $4,900. On these numbers December wins comfortably.

Change one input, though. If the roof sheeting over the bakehouse is due for replacement in the next two years, putting panels up now means paying to take them down and reinstall them. That cost could wipe out the whole gain.

Want to see what a December install would look like for your numbers? Check your options here. It takes about a minute, and your credit file isn’t touched just for asking.

You can run your own version through the cost-of-waiting calculator, using the lost discount as a one-off loss and the monthly bill saving as lost profit.

What mistakes cost businesses the most?

• Signing in December and assuming you’re locked in. You’re not. The install date decides.
• Oversizing the battery to “get more rebate”. Anything over 14 kWh earns 60%, then only 15% for capacity above 28 kWh, and nothing beyond 50 kWh. Size the battery on your evening and early-morning load.
• Accepting a rushed install. The CER warned retailers against rushing jobs to beat the May change. A poorly installed system costs far more than one year of deeming.
• Forgetting the tax side. A system costing $20,000 or more doesn’t get the instant asset write-off; it goes into the small business pool instead. Eligible businesses can write off assets under $20,000 in the year they’re first used or installed ready for use. (ATO) Ask your accountant how the point-of-sale discount affects the cost you claim.

When is waiting the smarter call?

The step-down is real, but it isn’t big enough to override a bad fit. Wait if:

• The roof needs work. Fix it first. Removal and reinstallation will cost more than the lost certificates.
• Your lease is ending or under review. Panels on a building you might leave in 18 months are a gift to the landlord. Our guide to lease option deadlines helps you settle that question first.
• You’re above 100 kW anyway. The small-scale deadline doesn’t apply in the same way.
• The only available installer is booked out. A quality installer in February beats an unknown one squeezing you in before Christmas.
• Cash flow before your peak is tight. If December is your biggest month and the repayments would land before the takings do, protect the peak.
• Your power use is about to change. A new oven line, a second coolroom or moving to longer hours changes the right system size. Size it once, properly.

Our page on when waiting is smarter covers the broader signals, and buy equipment now or wait uses the same approach for other gear.

How do businesses fund a solar and battery install?

Most pay for it in one of three ways:

• Cash, if the business has a buffer it can afford to drop before the busy season.
• Unsecured or cash-flow finance, typically $5,000 to $500,000 for trading businesses and sized on turnover and bank statements. This suits most systems under 100 kW.
• A property-secured loan from $20,000 to $5,000,000, where solar is part of a bigger upgrade such as a new coolroom, kitchen or factory fit-out.

The useful test: if monthly repayments come in under the monthly bill saving, the system pays its way from the first bill. Past credit issues and ATO debt are looked at case by case.

Beat the January step-down, if the timing is right

Rebate deadlines are useful. They force a decision that’s easy to put off for years. If solar or a battery was already on your plan, the next ten weeks are worth more than the ten weeks after them, and the funding often decides whether the installer can lock in your date.

Tell us what you’re installing and roughly when. The enquiry takes about 60 seconds and doesn’t involve a credit check, so your score stays exactly where it is. We don’t send your details to a pile of lenders, so there’s no flood of calls. A real person reads your answers, looks at the quote and your trading pattern, and calls you, including to say “wait until after the roof’s done” if that’s the honest answer. Please fill the form in accurately, with the system cost and your target install date, so the first option we bring you fits the job.

Find out where you stand →