Several searches ask versions of the same worry: will the money run out, is the rebate capped, will it end early? The answers differ depending on what you mean by the rebate.
The budget
The program launched on 1 July 2025 with a $2.3 billion budget. Demand ran far above forecast, and the budget was expanded to $7.2 billion, as reported. That figure is the government’s estimate of the cost of STCs created under the program, which is why a budget increase was needed rather than a change in the rules. Reports in late 2025 raised concerns about oversized batteries and rising costs, and the May 2026 changes responded to that.
How the rebate is capped
The rebate is capped in three ways:
| Control | How it works |
|---|---|
| Per property | One battery per property, 5 to 100 kWh usable |
| Per battery | Up to 50 kWh usable counts toward STCs |
| Tiering since 1 May 2026 | First 14 kWh at 100 percent, 14 to 28 kWh at 60 percent, 28 to 50 kWh at 15 percent |
Together these make a very large battery earn far less per kWh than a small one. See the tiers explained.
It tapers by design
The factor steps down every six months: 6.8 for May to December 2026, 5.7 from 1 January 2027, 5.2 from 1 July 2027, continuing down to 2030. So every month of delay has a known cost even if the program is unchanged. That is the most reliable thing to plan around.
Could it end early?
STCs are created on demand under the Renewable Energy (Electricity) Act rather than drawn from a fixed pot of grants, so the program does not simply run dry on a given day. But the government has shown it will adjust settings when cost overshoots, as it did on 1 May 2026. A further cut, a tighter cap or an earlier end are possible policy choices. Nothing in the published schedule says so, and we would not forecast one. For the end-date question, see cheaper home batteries program end date and what happens after 2030.
What this means for you
Homeowners who are ready to buy gain nothing from waiting, because the next scheduled step is lower. Installers should sign customers on a quote that states the installation date, since the factor applies by installation date. And installers should keep their STC buyer rate-locked: if policy changes cause a price swing, a locked rate protects your margin.
From the desk: treat “act now before it ends” sales pitches with care. The honest version is that the factor drops on a known date; the rebate itself is not ending next month.
Our battery STCs page has the schedule, the battery STC calculator has the sums, and pricing shows what STCs are worth to installers today.