Waiting 2 months could cost you up to 19% more in rebate value, Here’s why.
If you have been thinking about adding a solar battery to your home, now is the time to pay attention. Across Australia, battery rebates are changing from 1 May 2026, and the new rules will make the rebate less generous for many system sizes. The government says the discount will still sit around 30% across a range of battery sizes, but the way it is calculated is changing, and that will affect the value you receive depending on when you install and how large your battery is.
At Revolusun Power, we know many homeowners are not trying to “beat the system” they simply want the honest answer: should you install now, or wait? This guide breaks it down in plain English so you can make the best decision for your situation.
What is changing in May?
Right now, the rebate is still based on the current STC factor. From January to April 2026, the official STC factor is 8.4. From May to December 2026, that factor drops to 6.8. That is a reduction of about 19% in the overall factor used to calculate the rebate.
The bigger change is that the rebate becomes tiered by battery size from 1 May 2026. Under the new rules, the STC factor applies at:
- 100% for battery capacity from 0 to 14 kWh
- 60% for the portion above 14 kWh up to 28 kWh
- 15% for the portion above 28 kWh up to 50 kWh
In simple terms, the first part of a battery still receives strong support, but the larger the battery gets, the less support the extra capacity receives. That means bigger systems are affected more than smaller ones.
Before May vs after May: what is the real difference?
Here is the easiest way to understand it.
Before May 2026:
The rebate is calculated using the higher STC factor of 8.4, and the program remains broadly around the 30% discount range for many battery sizes.
After May 2026:
The STC factor falls to 6.8, which is about 19% lower overall. On top of that, battery capacity is treated in bands, with the middle band receiving only 60% of the support level and the upper band receiving only 15%. That means the rebate reduction is not equal across all battery sizes, it becomes much sharper as the battery gets larger.
So, the practical takeaway is this:
- If your battery is mostly within the first 14 kWh, the drop is smaller.
- If your battery relies on capacity above 14 kWh, the rebate becomes much less attractive after May.
- If you are planning a larger battery, the rebate loss on the higher-capacity portion is much more significant
Why This Matters for Your Savings:
A solar battery isn’t just about backup power, it’s about:
- Using your own solar energy at night
- Reducing reliance on the grid
- Protecting against rising electricity prices
But here’s the key:
Your return on investment depends heavily on the rebate:
If the rebate drops:
- Payback period increases
- Total savings reduce
- System value becomes less attractive
And if you delay:
- You lose rebate value
- You delay energy savings at the same time
1. Are battery rebates ending in Australia in 2026?
No, rebates are not ending, but they are reducing and becoming tiered from May 2026, which lowers their overall value.
2. How much will the rebate drop after May 2026?
The overall rebate calculation drops by around 19%, with additional reductions for larger battery sizes due to tiered eligibility.
3. Is it better to install a solar battery before May 2026?
For most homeowners, yes, especially if you want maximum savings and are planning a medium or large battery system.
4. Will solar batteries still be worth it after May?
Yes, but the financial advantage will be lower, meaning longer payback periods compared to installing before May.
5. What size battery is most affected by the rebate change?
Batteries above 14 kWh are most affected, with significantly reduced rebate support for larger capacities.
Battery rebates are not disappearing but they are becoming less generous.
From May 2026:
- Overall rebate drops by ~19%
- Larger batteries lose even more value due to tiering
Waiting could mean paying more for the same system and getting less support
Not sure if you should install now or wait?
At Revolusun Power, we help you make the right decision, not just the fast one.
✔ Compare before vs after May scenarios
✔ Understand your real savings
✔ Get expert guidance tailored to your home
