Australia is headed for its biggest year of rooftop solar growth ever – and the mid-scale boom is yet to come

In a year that has been all about big and small batteries – the latter still being installed by Australian households at the rate of about 1 gigawatt-hour per month – rooftop solar is shaping up to have its biggest year of growth on record as it rides the wave of the consumer energy revolution.

The latest data from industry analysts SunWiz shows that while month-on-month growth of newly registered rooftop solar capacity edged up only 1 per cent from September to October, the running tally for the year so far is the highest it’s ever been – and by some distance.

According to SunWiz, rooftop solar installs ranging in system size from 0-100 kilowatts (kW) reached a total of 305 megawatts (MW) in October, which is an increase of around 16 per cent on October 2025 (262 MW) and 11 per cetn on October 2024 (274 MW).

“It’s the strongest October of the last four years, and volumes have been above every prior year since June,” says SunWiz managing director Warwick Johnston. “The January–October tally is the highest on record and is running 41% ahead of the same point in 2025.”

As Renew Economy has reported, this stunning rooftop solar revival is not entirely surprising, given the boost the market has received from the federal Cheaper Home Batteries rebate, which requires discounted storage systems to be paired with PV.

This means those households that had not yet installed solar have taken the plunge with a battery included, which many households that already had rooftop PV are choosing to upgrade or replace their systems to better match their added energy storage capacity.

Meanwhile, the market is about to get another major boost from the federal government’s expansion of the Small-scale Renewable Energy Scheme to take in commercial and industrial installations sized between the former 100 kW ceiling of the subsidy, all the way up to 1 MW.

The game-changing SRES expansion came into effect for eligible mid-scale solar systems installed from October 01, but applications for small-scale technology certificate (STC) for mid-scale systems don’t open until mid to late November 2026.

As the SunWiz report notes, this means that some segments of the rooftop PV market have gone into decline in the wait to register small-scale technology certificates (STCs) for systems between 100 kW and 1 MW.

“Most notable was the decline (high percentage but low volume) in commercial volumes above 50 kW, whereas other segments were steady,” the report says.

From state to state, SunWiz shows that Victoria posted the strongest growth for the month, with the 60.2 MW of new rooftop PV capacity added across the state charting an 11 per cent jump on its September numbers.

The largest total capacity, however, was installed by New South Wales, at 89.9 MW, 5 per cent more than September. Queensland added 75.8 MW (−8%) for the month while Western Australia charted 5 per cent growth.

The average system size stayed much the same in October, rising just about 10 kW for the month after four months sitting just under 10 kW at 9.9 kW, SunWiz says.

Meanwhile, the uptake of home batteries is still going strong, regaining some of the momentum it lost after the May 2026 changes to the rebate, which reduced the overall discount and changed the settings to encourage households to install systems sized between 20-25 kilowatt-hours (kWh).

SunWiz says national home battery installations reached an estimated 1,043 megawatt-hours (MWh) – or just over 1 gigawatt-hour – in October 2026, up 9.7 per cent from September.

That makes it the first month above 1 GWh since the heady days of April, when a record 3,262 MWh was installed ahead of the rebate changes.

“This is the second straight rise after August’s small dip, and volumes are now nearly double the May low, though still about 68 per cent below April,” says Johnston.

“[This is a] continuation of recovery after [the] post-April slump, as customers come to the market in their own time, and in preparation for summer.”

Johnston says growth came mostly from systems sized at 20 kWh and above, with the 20-30 kWh segment accounting for 399 MWh of the month’s total capacity, ahead of 40-50 kWh at 273 MWh and 30-40 kWh at 210 MWh.

“Together, the bands from 20 kWh upward made up 85% of capacity [for the month,” he says. “At the smaller end, 10-20 kWh rose 3% to 150 MWh and 0-10 kWh was flat at 11 MWh.”

The national average home battery system size is also on the way back up, making its fifth consecutive monthly gain to rise to 26.74 kWh in October.