Up to half of the nation’s roofing area is suited to solar panels but is currently unused, with industrial suburbs accounting for most of this spare capacity.
According to new University of NSW (UNSW) research, 40 per cent of Sydney’s rooftops are capable of producing the output of a medium-sized coal-fired power station – or the equivalent of 22 per cent of the Sydney CBD’s energy usage.
Currently, solar panels only account for around one per cent of the city’s roof space.
The modeling shows that 38 per cent of Melbourne’s roofing is solar suitable, which if fully deployed would produce 12 per cent of the city’s electricity needs.
Brisbane’s roofing is even more up to the task with 45 per cent capacity, while even half of the roofing in fog-prone Canberra is suitable.
The research, prepared for the Australian Photovoltaic Institute (APVI), takes into account not just hours of sunshine, but variables such as the orientation of the prospective panels and the degree of overshadowing from vegetation or other buildings.
Not surprisingly, the highest potential is in suburbs or precincts with large expanses of flat factory and warehouse roofing.
The revelations of vast unused solar capacity follow a report of an emerging impediment to take up, because building owners and developers are using roofing that would not support the weight of a solar installation.
The Australian Financial Review reports that landlords are scrimping on development costs by installing “slender” roofs that meet engineering standards but do not have the strength to carry solar installations.
In the case of Sydney, 40 per cent utilisation would equate to 619 megawatts of capacity, capable of producing 777-gigawatt hours.
Sydney’s inner industrial Alexandria rates as having by far the most potential, with enough roof space for 109MW of capacity. The CBD and Rosebery in the city’s inner south also rate highly.
Melbourne’s industrial precincts of West Melbourne and Fishermans Bend have high potential, as does the apartment-heavy Docklands area.
Canberra’s high capacity reflects not so much industrial roofing but sprawling public buildings such as the Australian War Memorial and the Canberra Convention Centre.
The UNSW methodologies have been incorporated into Sunspot, an online tool site that allows property owners accurately to assess the solar power potential of their rooftops.
Launched on Thursday by federal minister for urban infrastructure and cities Paul Fletcher, Sunspot was developed by the APVI and UNSW and funded by the federal government’s Smart Cities and Suburbs program.
“Australia leads the world in rooftop solar, but there are still lots of potential for adding more solar, and it’s now the cheapest form of electricity generation, said APVI chair Renate Egan.
“Sunspot aims to give energy consumers the information they need to make a decision how much solar they should install, and how much they will save when they do.”
Initially, the site covers the six mainland capitals, but it will be expanded to other towns as the program expands.