For a 100 sqm home with a battery system to store maximum power at home, a 6.6 kW to 10 kW solar system is generally recommended, requiring approximately 16 to 26 solar panels. The total cost for such a system including a battery typically ranges from $11,000 to $27,000 AUD, depending on system size and component quality.

Solar System Size and Panel Count

The size of the system, measured in kilowatts (kW), is more crucial than the number of panels, and is primarily determined by your daily energy consumption and desire for maximum self-sufficiency, rather than house size alone. Most modern residential solar panels have a power output of 390 to 440 watts (W) and measure around 1.7 square metres. A 100 sqm home with a battery plan generally fits within the medium to high energy usage category, especially if aiming to store the maximum amount of power.

• System Size: A 6.6 kW system is a common size, but many Australian homes are moving towards larger systems of 9 kW to 10 kW to meet all energy needs and charge a battery effectively.

• Number of Panels: Based on typical 400W panels, a 6.6 kW system requires about 16-17 panels, while a 10 kW system needs around 25 panels.

• Battery Sizing: A common battery size for an average home is 10 kWh to 13 kWh for overnight use. A properly sized solar array ensures enough energy is generated during the day to fully charge the battery and power the home.

Estimated Costs (Installed with Battery)

The cost varies based on the size of both the solar array and the battery, the quality of components, and government rebates (STCs - Small-scale Technology Certificates) which can significantly reduce the upfront price.

System Size Battery SizeCost Range (Installed, after rebates)
6.6 kW - 10 kWh $14,780 – $18,780 AUD
5 kW - 10 kWh $12,000 – $17,000 AUD
10 kW - 15 kWh $21,940 – $26,940 AUD

Note that these are average costs, and prices for specific brands and systems can vary. For example, a 5kW inverter with a large 20kWh battery system from SAJ can be found for around $11,799 AUD (on sale at Solar Superstore as of February 2026).

Government Rebate
In Australia, there are two primary federal government rebate mechanisms designed to reduce the cost of solar and battery installations: the Small-scale Renewable Energy Scheme (SRES) for solar panels and the newly expanded Cheaper Home Batteries Program.

1. Solar Panel Rebate (SRES)

Commonly called the "solar rebate," this program works by creating Small-scale Technology Certificates (STCs) based on your system's expected energy generation until 2030.

• How it works: Installers typically apply the value of these certificates as an upfront discount on your quote.

• Value in 2026: For a 10 kW system, the rebate is worth approximately $2,160 to $2,760. For a 6.6 kW system, it is roughly $1,500 to $1,800.

• Phase-out: The value of this rebate decreases every January 1st until the program ends in 2030.

2. Cheaper Home Batteries Program

Launched in mid-2025, this program provides a substantial discount for home batteries, effectively acting as an extension of the STC system.

• Value for a 100sqm home: For a standard 10 kWh battery, you can receive a discount of approximately $3,020 to $3,300.

• Key 2026 Changes:

  • January – April 2026: High rebate value of approximately $302 - $336 per kWh of usable capacity.

  • From 1 May 2026: The rebate amount will drop (to roughly $244 - $272 per kWh) and a tiered system will be introduced, giving smaller rebates for capacity above 14 kWh.

• Eligibility: Batteries must be between 5 kWh and 100 kWh, installed by accredited professionals, and be "VPP-capable" (able to join a Virtual Power Plant).

3. State-Specific Incentives

Depending on where you live, you may be able to "stack" additional state-level support:

• NSW: Provides a VPP incentive of up to $1,500 for connecting your battery to a Virtual Power Plant.

• WA: The Residential Battery Scheme offers rebates up to $1,300 (Synergy customers) or $3,800 (Horizon Power).

• VIC: While state battery rebates have ended, the Solar Homes Program still offers a $1,400 solar panel rebate and interest-free loans.

• ACT: Residents can access zero-interest loans up to $15,000 through the Sustainable Household Scheme.

Would you like to know which battery brands currently meet the government's VPP-capable requirement to ensure you qualify for these rebates?