What changed in the battery rebate on 1 May 2026

On 1 May 2026 Australia’s Cheaper Home Batteries Program stopped paying a single flat STC factor on every usable kilowatt-hour and switched to a three-tier structure. The current tier-1 rate works out to about $252 per usable kWh at our assumed net STC price of $37 (verified 12 July 2026). If you are comparing an old quote with a new one, the gap is almost always this redesign — not a typo.

What happened on 1 May 2026?

From program launch on 1 Jul 2025 through 30 Apr 2026, the federal discount was a flat STC factor applied to eligible usable capacity. The factor itself stepped down once already — from 9.3 (July 2025) to 8.4 (January 2026) — but the maths stayed simple: usable kWh × factor × STC price.

From 1 May 2026 the factor is 6.8, and that factor is only fully applied to the first 14 kWh of usable capacity. Capacity from 14–28 kWh earns 60% of the factor. Capacity from 28–50 kWh earns 15%. Nothing above 50 kWh of usable capacity is counted for the federal rebate.

Before and after dollars

The table below uses the January–April 2026 flat factor of 8.4 versus today’s tiered 6.8, both at the same net STC assumption of $37. Figures are floored to whole STCs the same way the calculator does.

A household-sized 10 kWh pack lost a few hundred dollars. A 13.5 kWh Powerwall-class unit lost more, but still sits mostly inside the full-rate band. A 30 or 48 kWh system — the sizes that benefited most from the old flat maths — saw the steepest cuts because so much of their capacity now sits in the 60% and 15% bands.

Why did the rules change?

Public commentary from government and industry through late 2025 and early 2026 pointed to three linked problems. First, daily uptake rose far faster than the original budget assumed — from roughly a couple of hundred installs a day toward well over a thousand once awareness and installer capacity caught up. Second, the fiscal envelope for the program was revised upward (public figures moved from about $2.3 billion toward a $7.2 billion order of magnitude as the scheme was recalibrated). Third, the flat-rate design created an oversized-battery loophole: every extra usable kWh paid the same, so some quotes chased capacity for rebate dollars rather than for household load.

Tiers keep a strong incentive on the first ~14 kWh — the band where most Australian homes actually shift evening load — while sharply reducing the public subsidy on very large packs. That is a policy choice, not a quirk of STC market pricing.

What it means at each size

Around 10 kWh

You are entirely inside the 100% band. The hit is almost entirely the factor drop from 8.4 to 6.8, not the tiering. For many homes this remains the simplest “evening shift” size if daytime solar already covers the day.

Around 13.5 kWh (Powerwall 3 class)

Still almost fully inside the top tier (the band ends at 14 kWh). Federal support after May is about $3,367 at our STC assumption — down from the flat-rate figure, but still material when stacked with a state scheme.

Around 30 kWh

You cross both step-downs. Roughly the first 14 kWh are paid in full, the next 14 at 60%, and a couple of kWh at 15%. The federal cheque is still thousands of dollars, but it is no longer linear with size. Size the battery to your evening load and any VPP rules — not to “max the rebate”.

Around 48 kWh and above

Most of the pack sits in the discounted bands, and capacity above 50 kWh usable earns nothing federally. Large systems can still make sense for multi-occupancy, workshops, or high evening loads — just run the numbers without assuming flat-rate dollars.

What happens next on the schedule?

From 2027 the program continues with announced step-down dates every January and July through 2030. Exact future STC factors are filled in as the Clean Energy Regulator publishes them; until then our schedule table marks those rows as announced dates without a locked factor. This page’s slug stays evergreen — when the next factor lands, we update the data file, rebuild, and note the revision on What changed.

Calculate my rebate at current rates

Sources

• Cheaper Home Batteries Program — Clean Energy Regulator
• Federal battery rebate hub — current rates and eligibility
• Site changelog — every data-file update we publish