Rooftop Solar Installation Rates Trending up as Monthly Volumes Drop

Australia’s rooftop solar market has slowed with the latest monthly data from industry analyst SunWiz revealing that national installation volumes dropped off 7% in August compared to the previous month.

The latest numbers from SunWiz show a total 277 MW of solar panels were installed on rooftops across Australian homes and businesses in August, compared to 299 MW in July – a 22 MW decrease.

SunWiz managing director Warwick Johnston said the nationwide rooftop solar installation market had cooled after an “explosive” July, but highlighted the year-to-date numbers are in line with the straight-line average.

“National market volumes are down 7% on last month, however, volumes are on par with the trend,” he said, noting that the August rooftop solar total is the 13th best month on record.

Johnston said the 277 MW installed in August is above the volumes seen for the same period in 2021 and 2022 but below those observed in 2023.

He also noted that the year-to-date numbers remain 5% ahead of the figures observed at the same time last year.

Johnston said all state volumes dropped off in August, except Tasmania which stayed level. The Northern Territory experienced the biggest decline with installation rates down 19% on the previous month. The Queensland market suffered a 10% drop-off, while New South Wales (8%) and Victoria (7%) also delivered significant declines.

On system sizes, the data shows that in the 15-100 kW commercial rooftop solar sector the 30-50 kW segment was the only range to show growth, up 1% month-on-month. All other commercial segments declined – highlighted by a 20% decrease in 75-100kW systems – but remained on par with or over their straight-line averages which are on the up in 2024.

Installations in the residential segments also declined in August compared to the previous month but remained on in line with or above their straight-line averages, except for the 4-6 kW category which dipped below the trend.

With the trend in the 15-100 kW segments still up, the average system size increased to 10.09 kW in August, the second-highest month in recent times.