Can I get a battery without solar panels?

Yes, you can install a battery without solar panels. However, the economics are less favourable since you'll be charging from grid electricity rather than free solar. Batteries work best when paired with solar to store excess daytime generation for evening use.

What happens during a blackout?

Most batteries can provide backup power during outages if configured with a backup gateway or similar device. However, during VPP events, Synergy may use your battery capacity, so backup reserve is not guaranteed. Discuss backup requirements with your installer.

How long does installation take?

Due to high demand from the rebate program, current wait times for battery installations can be 3-6 months from order to installation. It's recommended to get quotes and book early. The actual installation typically takes 1-2 days.

Which batteries are approved for the WA rebate?

Only batteries on Synergy's Supported Solution List (SSL) are eligible. The SSL covers many popular battery brands and is updated regularly — check Synergy's website for the current approved list before you buy.

Can I opt out of the VPP program?

VPP participation is mandatory for rebate recipients for the 2-year contract period. After the contract expires, you may have the option to continue (and keep earning credits) or opt out. However, opting out means losing the ongoing VPP income.

Do batteries work in Perth's hot climate?

Yes, modern lithium-ion batteries are designed for Australian conditions. Installation location matters — batteries should be installed in a cool, well-ventilated area away from direct sunlight. Garages are common; avoid hot sheds. Proper installation ensures optimal performance and longevity.

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

Up to $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

Rebate amount: $130/kWh up to $1,300 for Synergy network customers (10 kWh cap). VPP + Battery Rewards opt-in is a precondition.

Eligibility requirements

Australian permanent resident, 18+ years old
Synergy customer in Western Australia
Primary residence or investment property (with landlord consent if renting)

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, 2-6 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

How to size your battery

Choose the right capacity for your household needs

Sizing formula: daily usage (kWh) × 0.8 (DoD) × 1.2 (inefficiency) = required capacity

Step-by-step sizing

Calculate daily usage: Monthly bill usage ÷ 30 days
Example: 600 kWh/month = 20 kWh/day
Determine evening usage: Typically 40-60% of daily usage occurs after solar production
Example: 20 kWh × 50% = 10 kWh evening usage
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
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

Average households, 3-4 people, typical usage

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)

How batteries help: instead of exporting excess solar (which may be curtailed), store it in your battery for evening use. This maximises your solar investment and provides energy independence.

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 — run the calculator for your own figure.

System cost (installed)$15,000

WA state rebate-$1,300

Federal rebate (if eligible)-$4,500

Net cost$9,200

Illustrative annual savings

Modelled for 6.6kW solar + 13.5kWh battery, Synergy A1/Midday Saver, evening-peak usage pattern. VPP credits require ongoing VPP participation. Your results depend on usage and system sizing.

Bill savings (avoiding peak rates)$800-1,200/year

VPP event credits$200-400/year

Export curtailment avoided$100-300/year

Total annual benefit$1,100-1,900/year

Frequently asked questions

Ready to explore battery options?

Get personalised battery sizing recommendations and compare quotes from trusted SAA-accredited installers in Perth

Get battery assessment Compare installer quotes

Get quotes from SAA-accredited installers