Buying Guide

How to Buy Home Batteries

Everything you need to know before buying a home battery. Size it right, choose wisely, and avoid common mistakes.

Check your battery rebate eligibility

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Current battery rates end May 1, 2026 · 18 days remaining

Headshot of Jos Aguiar, Solar Evangelist at Why Solar
Written by Jos Aguiar
·January 2026·10 min
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What Size Battery Do You Need?

Your Evening UsageRecommended SizeBackup DurationTypical Home
Low evening usage (5-8 kWh)5-6 kWh4-6 hours essentialsSmall household, mostly daytime use
Average evening usage (10-15 kWh)10 kWh8-10 hours essentialsAverage family, some evening appliances
High evening usage (15-20 kWh)13-15 kWh12+ hours essentialsLarge family, AC, pool pump
Very high / whole home backup20+ kWh24+ hours whole homeLarge home, EV, complete independence
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Pro Tip: Match to Solar Export

Your ideal battery size is roughly equal to your daily solar export. Check your inverter app or ask your retailer for your average daily export figure.

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Check Your Battery Rebate

Enter your postcode to check rebate eligibility in your area.

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Current battery rates end May 1, 2026 · 18 days remaining

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Over 3.6 million homes already claiming rebates

Buying Checklist

checkCheck usable capacity (not just total capacity)
Critical
checkCompare continuous power output (kW)
High
checkVerify warranty terms and what it covers
Critical
checkConfirm backup capability if needed
High
checkCheck compatibility with your inverter
High
checkAsk about monitoring and app features
Medium
checkConfirm VPP compatibility if interested
Medium
checkGet installation quote separately itemised
High

Common Mistakes to Avoid

warningBuying too large a battery

Problem: Spending extra money on capacity you wont use daily. Payback takes longer.

Solution:Match battery size to your evening usage and solar export, not maximum capacity available.

warningIgnoring power output (kW)

Problem: A large battery with low power output cant run high-draw appliances like air conditioning.

Solution:Check both capacity (kWh) AND power output (kW). Match power to your peak demand.

warningAssuming all batteries do backup

Problem: Many batteries require additional hardware for blackout backup, adding $500-$2,000.

Solution:If backup is important, confirm it is included and which circuits will be backed up.

warningNot checking inverter compatibility

Problem: Some batteries only work with specific inverters. May need expensive upgrades.

Solution:If adding to existing solar, confirm the battery works with your current inverter.

Battery installations are a bigger investment than panels alone, so installer stability matters even more. Over 200 solar companies have collapsed in Australia since 2010, and 1 in 6 solar homes now have no workmanship warranty. Before committing, check our collapsed solar companies tracker and make sure your installer has been trading for at least 5 years.

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See Your Battery Rebate Amount

Enter your postcode to see your estimated rebate amount.

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Current battery rates end May 1, 2026 · 18 days remaining

verifiedVerified Local Installersthumb_up100% Free ServiceshieldNo Obligation

Over 3.6 million homes already claiming rebates

Questions to Ask Installers

1What is the usable capacity vs total capacity?
2What is the continuous and peak power output?
3What warranty comes with the battery? What does it cover?
4How many cycles is the battery rated for?
5Does this battery support backup during blackouts?
6Is the battery compatible with my existing solar inverter?
7What monitoring/app is included?
8Is this battery compatible with VPP programs?
9What is the installation timeline?
10Are there any ongoing costs or subscriptions?

Helpful Resources

The next step

If you have any questions about the information in this guide, feel free to get in touch:

If you're considering a home battery system, Jos and the team can help you get quotes from trusted, pre-vetted local installers:

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Headshot of Jos Aguiar, Solar Evangelist at Why Solar

Written by

Jos Aguiar

Solar Evangelist

Passionate about making solar simple and accessible for every Australian household. Jos breaks down complex energy topics into practical advice so homeowners can make confident decisions about solar, batteries, and energy independence.

Learn more about Jos Aguiar
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