The figure brings the total capacity of rooftop solar in Australia to over 13 gigawatts as of the end of 2020.
Last year, over 362,000 rooftop installations were issued with small-scale renewable energy scheme certificates under the Clean Energy Regulator's Small-scale Renewable Energy Scheme. This is an increase of 28% on 2019 figures, when 283,991 installations were issued STCs.
The majority of RTS installations are on domestic properties with the remainder on commercial and industrial premises.
"Sustained low technology costs, increased work from home arrangements and a shift in household spending to home improvements during COVID-19 played a key role in theincrease of rooftop solar PV systems under the SRES," Clean Energy Regulator's executive general manager Mark Williamson said.
In 2020, New South Wales recorded the highest number of new solar PV installations at 108,922, followed by Queensland (86,912), Victoria (71,798), Western Australia (47,653) and South Australia (35,599).
In capacity terms, a total of 3GW of rooftop solar PV capacity was installed nationally in 2020, a 40% increase on the 2.2GW added in 2019. For 2021, between 3.5GW and 4 GW of new rooftop solar capacity is expected to be installed, mostly driven by increasing system size, with the average RTS PV system now between 8 and 8.5 kilowatts.
Between 2010 and end-2020, a total 13.258 GW of RTS capacity has been installed under the SRES. This figure excludes rooftop solar accredited under the Large-scale Renewable Energy Target (LRET).
"Australia is one of the sunniest places on the planet. We lead the world in PV capacity on a per capita basis at 591 watts per person which is almost eight times the worldwide average," CSIRO Senior Experimental Scientist Michael Ambrose said.
CSIRO chief executive Dr Larry Marshall added that renewables are now "cost competitive with conventional power, letting market forces take over to drive a global transition to lower emissions".