Modular and upgradeable systems have become an excellent answer to the question of ‘what’s next in household energy?’
When Fronius launched its GEN24 inverter in Australia three years ago, the market was not yet buzzing with battery rebates or urgent conversations about grid independence. The company had to build for a different timeline.
“In 2020, we saw an opening in the market – people who wanted to take control of their home energy,” says Joel Atkins, Head of Sales at Fronius Australia and New Zealand.
“The battery costs were still a hurdle, but we realised we could give customers the option to take that step later without starting again.”
The GEN24 was designed to do just that.
As a standard photovoltaic (PV) inverter it manages solar generation for a home, but with a software upgrade it transforms into a hybrid system ready to connect to battery storage – no rewiring, no hardware replacement, no waste.
That foresight is paying off now.
With the Federal Government’s Cheaper Home Batteries Program reducing the cost of home storage systems by around 30 per cent, early adopters of Fronius equipment are already poised to take advantage.
“We’ve seen a fourfold increase in GEN24 upgrades since the rebate was announced,” Atkins says.
General Manager at GI Energy.
“The customers already have the inverter, the data, the hardware – it’s just a matter of software and a battery install.”
There are over 65,000 GEN24 units installed across Australia and New Zealand. Many of these were sold as standalone PV systems with the promise of future battery-readiness – a promise now proving to be worth its weight in lithium.
Longevity as strategy
For Fronius, the upgrade path is part of a deep sustainability ethos rooted in the company’s 80-year history.
“Fronius started in 1945 by developing battery chargers to stop car batteries from going to waste,” Atkins says.
“That same philosophy – of extending product life, not discarding it – runs through everything we do, including the GEN24.”
That focus on longevity is as technical as it is ethical.
The GEN24 uses active cooling – a rare choice in the industry, where passively cooled inverters are more common due to lower manufacturing costs.
“We use a mechanical fan and a specially designed heat sink to keep the inverter cool,” Atkins says.
“That means we can maintain peak power performance up to 45 degrees ambient temperature. There’s less stress on the components, and you don’t lose efficiency during heatwaves.”
This choice costs more upfront, but according to Atkins, it dramatically extends the life of the unit and preserves its performance in harsh Australian conditions.
“Longevity is part of sustainability,” he says.
“A five-year product that needs replacing isn’t a green solution.”
The installer’s perspective
For Matt Williams, General Manager at GI Energy with over a decade’s experience in solar, reliability is crucial.
“It’s imperative,” Williams says.
“We’ve seen so many manufacturers come and go. If a product fails, we need to know it’s going to be supported, and that it won’t come back to bite us.”
Williams says the GEN24’s dependability makes it a smart recommendation – not just for his customers, but for his own business risk. The fact that it can be upgraded with minimal disruption is a major bonus.
“It’s a much nicer conversation when you’re not telling a customer they need to pull out a perfectly good inverter,” he says.
“With the GEN24, we can add a battery seamlessly. There’s no waste, no confusion – it’s just a clean upgrade.”
With the new rebate sparking a surge in customer interest, Williams says his team has been flat out with inquiries.
“I’ve never seen anything like it,” he says.
“The number of calls is off the charts. We knew this would be popular, but it’s still blown us away.”
That demand is now moving from the inbox to the installation queue.
For customers who already have a GEN24, the process is relatively simple: check their usage and generation data, recommend a battery size, and activate the hybrid functionality through a software key.
“We try to keep it really straightforward,” says Williams.
“We’ve done enough of these now that it’s become second nature.”
Timing is everything
One of the challenges now, both Williams and Atkins says, is managing stock and delivery logistics as the rebate drives uptake faster than expected.
But the upgradeable pathway has given both installers and homeowners a head start. Many early GEN24 adopters have already accumulated solar usage data through their Fronius monitoring platform, allowing for smarter battery sizing.
“Without data, you’re guessing,” says Atkins.
“With data, we can model exactly what battery size is right for the customer and deliver a solution that genuinely supports energy independence.”
That data visibility is part of a broader strategy Fronius calls its “24 Hours of Sun” vision. The strategy seeks to enable energy self-sufficiency not only during sunlight hours, but around the clock through smart generation, storage, and consumption.
“Our inverters manage production, our new battery handles storage, and our EV chargers optimise usage,” says Atkins.
“It’s a full loop, and the GEN24 is the heart.”
Reserva battery: The next phase
That loop will tighten further this year when Fronius launches its own home battery – Reserva. It is designed to work natively with the GEN24, giving Fronius full control over the inverter-battery ecosystem.
“Previously we partnered with BYD, which has been a great relationship,” says Atkins.
“But now with Reserva, we’ve developed the battery management system in-house. It improves commissioning, data analysis, and lets us push over-the-air updates in future.”
Williams says that integration is important – not just technically, but in terms of accountability.
“One manufacturer, one point of call,” he says.
“That’s a big deal when something goes wrong. You don’t want finger-pointing between brands – you want a fix.”
Advice for customers
With the subsidy only applying to the first battery installation, Williams says his team is encouraging customers to think years ahead.
“We’re telling people: install the biggest battery that your budget and solar generation can support,” he says.
“You’ll only get the rebate once. And with more EVs, more electric homes, and the rise of virtual power plants, you’re going to want that capacity.”
The Reserva battery is expandable, but sizing correctly up front makes the most of the subsidy.
“There’s no one-size-fits-all,” says Williams.
“But there’s definitely a right-size-for-you. And with a GEN24 already on the wall, you’ve got a huge head start.”
Not just a trend
Atkins agrees. While the current rebate has brought battery storage into focus, the broader shift toward energy autonomy is a long-term market transformation.
“This isn’t just a spike in demand – it’s a shift in mindset,” he says.
“People want control. They want resilience. And they want products that won’t end up in landfill.”
With GEN24 customers cashing in on a decision made years ago, the case for planning ahead has never been stronger.