Battery Storage Calculator Australia
Determine if adding battery storage to your solar system makes financial sense. Includes current federal Cheaper Home Battery Program assumptions and state eligibility prompts.
Federal Cheaper Home Battery Program
The Australian Government battery discount is delivered through small-scale technology certificates (STCs) for eligible battery systems from 5-100 kWh nominal capacity. It applies to the first 50 kWh of usable capacity and may be combined with separate state, retailer, or VPP offers where those programs are open.
Current rate: May-Dec 2026 STC factor of 6.8, valued at $40 per STC before retailer fees
Capacity tiers: First 14 kWh at 100%, next 14 kWh at 60%, then up to 50 kWh at 15%
Stacking: Check current program rules before assuming another offer can be combined
Declining value: Rebate decreases annually from 2026-2030
When Does Battery Storage Make Sense?
Battery storage is most beneficial if you have time-of-use electricity tariffs, high evening usage, or want backup power during outages. Current federal support can reduce eligible battery costs, but payback still depends on usage and tariff details.
Finding Your Electricity Rates
Check your electricity bill or provider's website for your exact rates. Rates vary significantly between providers. If you have a time-of-use tariff, enable it below and enter your peak/off-peak rates for more accurate savings calculations.
Battery System Details
Enter your current setup and battery requirements
Common sizes: 6.6kW (standard), 10kW (large home), 13.2kW (very large). Use slider for custom sizes.
Common: 10kWh (small), 13.5kWh (Powerwall), 20-30kWh (large). Federal rebate capped at 50kWh usable.
Average Australian home: 15-25 kWh/day. Large homes with pool/AC: 40-100 kWh/day
Percentage of daily usage between 4pm-10pm
Average Australian rates: $0.25-$0.35/kWh. Check your electricity bill for your exact rate.
What you earn for excess solar sent to the grid. Typical range: $0.05-$0.15/kWh. Premium plans may offer up to $0.20/kWh.
Select Your Location
Choose your location to see battery storage analysis
About the Cheaper Home Battery Program
Federal government initiative to make home batteries more affordable (2025-2030)
Program Details
- ✓Rebate Amount: STC-based discount using the current program factor and STC value
- ✓Maximum Eligible Capacity: STCs apply to the first 50 kWh of usable capacity
- ✓Eligible Batteries: 5-100 kWh nominal capacity
- ✓Who Can Apply: All Australian households, businesses, and community organisations
- ✓Other offers: May be combined with eligible state, retailer, or VPP incentives where available
Requirements & Timeline
- •Battery must be new (no second-hand systems)
- •Must be installed with new or existing solar PV system
- •Battery, equipment, and installer must meet current program accreditation requirements
- •Discount applied automatically by retailer/installer
- ⚠Important: Rebate decreases annually until 2030
How it works: The rebate is delivered through Small-scale Technology Certificates (STCs) under the Small-scale Renewable Energy Scheme. Your installer will typically arrange the rebate and apply it as an upfront discount on your battery purchase. From May 2026, the calculation tapers support above 14 kWh of usable capacity.
State incentives: WA has an open residential battery rebate for eligible customers. NSW VPP incentives, ACT finance, and other state, retailer, council, and VPP offers change often, so confirm current eligibility before treating them as savings.
Important Considerations
Battery degradation: Battery capacity reduces over time. Most warranties guarantee 70% capacity after 10 years.
Backup power: Backup duration depends on what appliances you run during an outage. Essential loads only (lights, fridge) last longer.
Installation requirements: Some homes may need electrical upgrades to install battery systems safely.
Program changes: The federal battery rebate steps down through 2030, so installation timing affects the available support.
Understanding Battery Storage Value
Current Federal Rebate
The Cheaper Home Battery Program provides STC-based support for eligible systems. From May 2026, the calculation tapers support above 14 kWh of usable capacity.
Time-of-Use Savings
Batteries let you use stored solar during expensive peak periods (often 40-55c/kWh) instead of cheap off-peak rates.
Backup Power
Keep essential appliances running during blackouts. A 13.5kWh battery can power lights and fridge for 6+ hours.
Self-Consumption
Increase solar self-consumption from 30% to 60-80%. Use more of your own solar instead of exporting at low feed-in rates.
Energy Security
Reduce dependence on the grid and protect against future electricity price rises. Lock in energy costs with your own storage.
Long Warranties
Most quality batteries come with 10-year warranties guaranteeing 70% capacity. Expected lifespan is 15-20 years.
Battery Rebates by State
Federal - All States
The Cheaper Home Battery Program provides STC-based support for batteries between 5-100kWh. STCs apply to the first 50 kWh of usable capacity, with tapered support above 14 kWh.
Available nationwide for eligible systems
Victoria
Solar Victoria battery loans are not treated as currently open support here. Victorian households should model batteries against evening usage, tariffs, and federal battery support.
No current state battery deduction included
South Australia
Check current state, retailer, and VPP offers before assuming a separate statewide battery subsidy. Most households should start with the federal program and compare installer quotes.
Confirm current offers before relying on savings
Western Australia
WA has a residential battery rebate for eligible Synergy and Horizon Power customers, plus possible no-interest battery finance. Confirm provider eligibility before treating it as a saving.
Up to $1,300 or $3,800 if eligible
Other States
NSW VPP offers, ACT finance, WA battery support, and local retailer programs can apply differently. Treat loans and VPP offers separately from guaranteed rebates.
Federal support available nationwide for eligible systems
Battery ROI by State
| State / region | Where batteries tend to work best | Check before you buy |
|---|---|---|
| NSW / ACT | Strong for homes with time-of-use pricing and evening usage | Compare feed-in tariff loss against peak-rate savings |
| VIC | Often strongest with high peak rates and evening usage | Solar Victoria battery loans are not counted as open support here |
| QLD | Useful for high air-conditioning loads and backup needs | Regional tariffs and export limits vary by network area |
| SA | Can perform well where exports are constrained or wholesale swings are high | Confirm any state or retailer battery program is still open |
| WA / TAS / NT | Most case-by-case; backup power and self-consumption usually matter most | WA has a battery scheme; retail choice and export rules differ elsewhere |
Battery Storage FAQ
Is battery storage worth it in Australia?
With the federal battery discount reducing upfront costs, batteries are worth modelling for more homes. They work best for homes with high evening usage, time-of-use tariffs, or those wanting backup power. Our calculator helps you determine if it makes sense for your situation.
What size battery do I need?
Most Australian homes benefit from 10-15kWh batteries. This covers typical evening usage of 8-12kWh. Larger homes with pools, air conditioning, or EVs may need 20-30kWh. Our calculator factors in your usage patterns to recommend the right size.
How long do home batteries last?
Quality lithium batteries like Tesla Powerwall, BYD, and Sungrow typically last 15-20 years. Most manufacturers warrant 70% capacity after 10 years. Our calculations use conservative 2% annual degradation to give realistic long-term projections.
Can I add a battery to my existing solar system?
Yes, batteries can be added to most existing solar systems. Some older inverters may need upgrading, or you can install an AC-coupled battery that works with any inverter. The federal rebate applies to both new installations and retrofits.
Compare battery support before asking for quotes
Battery pricing should be separated from solar pricing. Check federal battery support, state programs, warranty terms, backup hardware, and usable capacity before comparing payback.
Last reviewed May 2026
Figures and policy settings change. Use this as a planning guide and confirm details before signing a quote.