Australia’s Battery Boom: Why Size, Retrofits, and Product Fit Now Matter More Than Ever

Australia’s Battery Boom: Why Size, Retrofits, and Product Fit Now Matter More Than Ever

Australia’s battery market is booming — but not booming equally for all.

In the past two months, SunWiz data has revealed a wave of structural change in how the market behaves — and which brands are positioned to benefit.

Here’s what’s happening — and why product-market fit matters more than ever.


More Batteries Than PV — A New Market Milestone

For the first time in Australia’s history, more battery systems were sold than PV systems in a single month.

👉 In May, there were 1.4 battery systems installed for every PV system.
👉 Retrofit demand is surging.
👉 ESS-only systems grew the fastest — and may soon become the dominant purchase path.

This milestone signals a major shift in the market.

Retailers report being swamped with inbound calls from existing solar owners wanting to add batteries. The federal battery subsidy is driving this interest — and changing what consumers buy.


Bigger Batteries Are In

The average battery size jumped to 15kWh in May — well above the typical 10kWh norm.

Why? The federal subsidy is giving consumers a choice:

👉 Pocket the subsidy to save $
👉 Or use it to buy a larger battery

Many are choosing the latter. If a $10k battery now costs $6700 after subsidy — why not use that same $10k to buy a 15kWh system instead?

Brands that offer stackable battery designs are well placed to take advantage of this trend. These products allow customers to easily scale up capacity — in line with evolving value propositions under the new subsidy.

Monolithic battery designs face a challenge here: they can’t easily scale to the 15kWh sweet spot without significant redesign or added installation complexity.


Retrofits Drive the Market — Product Flexibility Wins

Right now, the battery boom is favouring brands that are easy to retrofit into existing PV systems.

Retailers will eventually pivot back to outbound PV+ESS sales — but today’s inbound demand is dominated by retrofit buyers.

That means:

  • Batteries must be easy to integrate into legacy PV systems

  • Inverters must support flexible configurations

  • Product flexibility is a key source of competitive advantage

Hybrid vs non-hybrid inverter trends provide further insight.

  • 80% of ESS installs used hybrid inverters last year

  • 18% of PV-only installs used hybrids — future-proofing for battery add-ons

  • Overall, hybrids made up one-third of combined PV + ESS installs in 2024

Brands offering hybrid-capable solutions — or designing products with retrofit flexibility in mind — are best positioned for ongoing success.


Product-Market Fit Will Define Brand Success

The Australian battery market is moving fast — and success is no longer driven solely by brand reputation or pricing.

Product-market fit now defines the winners.

Brands that align with the following trends will lead the market:

✅ Stackable batteries that enable consumers to easily upsize
✅ Retrofit-friendly designs for today’s inbound demand
✅ Hybrid inverter compatibility to serve both PV+ESS and ESS-only markets

Conversely, brands ignoring these dynamics risk losing relevance.


Conclusion

Australia’s battery boom offers an important case study for storage markets globally.

When incentives align with consumer value — and market architecture evolves quickly — product-market fit becomes a decisive factor.

SunWiz’s expanded Battery Market Subscription provides near-perfect vision into these trends, helping manufacturers, distributors, and retailers navigate the market with confidence.

The opportunity is enormous — but it won’t be captured equally by all.

#BatteryMarket #EnergyStorage #Retrofits #HybridInverters #ProductMarketFit #SunWizInsights


Want to track these trends monthly?

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📊 Volumes & attachment rates
📊 Leading brands & sizes
📊 Retrofit trends & inverter topology
📊 State-by-state breakdowns
📊 Competitor tracking & market strategy

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