Updated for 2026
Your complete guide to home batteries in WA
Understand rebates, sizing, costs, and returns for battery storage in the Synergy and Western Power network
The findings
$4,013 in rebates
Stack state ($1,300) and federal (~$2,713) rebates on a 10 kWh Synergy battery to significantly reduce upfront costs
Earn VPP rewards
Get paid $0.70/kWh during grid events through Synergy's Battery Rewards program
Energy independence
Store solar energy for evening use and protect against export curtailment
WA Residential Battery Scheme
State government rebate program launched August 21, 2025
Eligibility requirements
- Australian permanent resident, 18+ years old
- Synergy customer in Western Australia
- Primary residence or investment property (with landlord consent if renting)
- Battery with minimum 5kWh usable capacity
- Battery on Synergy's Supported Solution List (SSL)
- Ongoing internet connection for VPP participation
- Battery installed after July 1, 2025
Federal battery rebate
In addition to the state rebate, eligible households qualify for the federal Cheaper Home Batteries program, delivered as rebate certificates (STCs: Certificates whose value comes off the price of solar panels and batteries at install.) under the federal small-scale rebate scheme (SRES: The federal scheme behind the solar and battery rebate (STCs).). For a 10 kWh battery in Perth at the 6.8× factor in force today (it steps down to 5.7× on 1 January 2027):
- Approximately $2,713 federal rebate (varies with battery size)
- Capacity tapers above 14 kWh (60% rate) and 28 kWh (15% rate)
- Combined total at 10 kWh: about $4,013 (Synergy). Bigger batteries get a bigger federal rebate.
Synergy Battery Rewards (VPP)
Western Australia's first large-scale Virtual Power Plant
The Battery Rewards program connects home batteries into a virtual power plant, allowing Synergy to use stored energy during peak demand. In return, you earn credits and help stabilise the grid.
How you earn
Event credits
$0.70 per kWh exported during VPP events (up to 30 events/year, 2-4 hours each)
Offset credits
Credits for battery charging and holding capacity
Year-round savings
Reduce bills by storing cheap solar and avoiding peak rates
Program details
- Contract:
- 2-year term
- Events:
- Up to 30 per year, typically 2-4 hours
- Control:
- Synergy can charge/discharge battery during events (household load supplied first)
- Backup:
- Backup reserve not guaranteed during VPP events
How to size your battery
Choose the right capacity for your household needs. Still deciding whether a battery stacks up at all? Start with the honest worth-it arithmetic.
Step-by-step sizing
- 1
Calculate daily usage: Usage on your bill (kWh) ÷ days on the bill
Example: 1,200 kWh on a 60-day Synergy bill = 20 kWh/day
- 2
Determine evening usage: Typically 40-60% of daily usage occurs after solar production
Example: 20 kWh × 50% = 10 kWh evening usage
- 3
Apply efficiency factors: Account for Depth of Discharge (80%) and round-trip efficiency (80-90%)
Example: 10 kWh × 0.8 × 1.2 = 9.6 kWh minimum capacity
- 4
Add buffer: Consider backup needs and future usage growth
Recommended: 13.5 kWh battery for this household
Common battery sizes
5-7 kWh
Small households, 1-2 people, low evening usage
10-13.5 kWh
Most popularAverage households, 3-4 people, typical usage
15-20 kWh
Large households, 5+ people, high usage or backup needs
Key considerations
- Efficiency:
- Look for 90%+ round-trip efficiency
- Lifespan:
- Modern lithium-ion batteries last 10-15 years
- Warranty:
- Check cycles and throughput guarantees
- Compatibility:
- Ensure it works with your existing solar inverter
- Location:
- Install in cool, ventilated area (Perth heat considerations)
Why batteries matter: export limiting
Understanding Western Power's solar export restrictions
Since February 14, 2022, Western Power has implemented export limiting to manage grid stability. This affects how much solar energy you can send back to the grid.
Export limits
- Systems ≤5kW:
- Must be remotely controllable (can be turned down/off during emergencies)
- Systems >5kW:
- Limited to 1.5kW or 5% of inverter capacity (whichever is greater)
With export limiting becoming more common during peak solar production (10am-2pm), batteries ensure you capture and use all your solar generation rather than losing it to curtailment.
Return on investment
Understanding battery payback periods with WA rebates
Illustrative example: 13.5 kWh battery system
A modelled scenario, not a quote. Your numbers depend on your usage and the install price you are quoted, so run the calculator for your own figure.
- System cost (installed)
- $15,000
- WA state rebate
- -$1,300
- Federal rebate (if eligible)
- -$3,631
- Net cost
- $10,069
Illustrative annual savings
- Bill savings (avoiding peak rates)
- $800-1,200/year
- VPP event credits
- $40-80/year
- Export curtailment avoided
- $100-300/year
$940-1,580/year
Total annual benefit
For the full breakdown of what drives an installed price — the three cost layers, how to read a quote, and why two quotes for the same battery can differ by thousands — see what a solar battery actually costs.
Frequently asked questions
Related guides
How to size a home battery for Perth: matching capacity to your evening load
Too small a battery leaves you buying grid power at 33c/kWh. Too large and you're paying for storage you never use. Here's how to calculate the right battery size for your household.
Is a home battery worth it in Perth in 2026? The honest numbers
Battery prices have fallen significantly, but so have export rates. Here's a straightforward analysis of home battery ROI in Perth across different tariffs, system configurations, and usage scenarios.
WA Battery Scheme 2026: how to claim your $1,300 battery rebate
The WA Battery Scheme gives eligible Synergy customers up to $1,300 off a home battery. Here's exactly who qualifies, how the application works step by step, and what to do if your claim stalls.
Virtual power plants in Perth: what's available and is it worth it?
Virtual power plants (VPPs) let solar battery owners earn money by sharing stored energy with the grid. Here's the honest picture of what's available in Perth in 2026, what you actually earn, and whether WA is ready.
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