Solar car parks: Australia’s great untapped PV potential

Australia has become a world leader in the uptake of rooftop solar PV, but one of the assets that remains largely untouched are outdoor car parks.

A new study from the ANU suggests there are about 40,000 outdoors parking locations with more than 80 car spaces, and if just 60 per cent of this area was covered with solar panels that would come to 12.3 gigawatts (GW) of capacity and generate 34 terawatt hours (TWh) a year.

“The potential of solar in parking lots remains largely untapped,” says ANU researcher Dr Shahid Ali.

“Transforming car parks by roofing them with solar panels keeps cars cool, preserves undeveloped land for other purposes, and generates significant revenue from electricity sales.

“Moreover, on-site solar power could seamlessly support EV charging stations, allowing customers to charge their vehicles.”

By the end of September, Australian had bought 69,962 new EVs in the year to date, up from 65,753 sold over the same period in 2023.

The concept for the research actually sprang out of what big industrial emitters can do to switch to renewables, Ali told Renew Economy. 

Conversations with these organisations revealed the only locations for solar panels would be rooftops and car parks, as much of the sites need to be kept clear. But digging deeper, Ali found little policy support for the concept. 

“What we have seen is there is no policy at government level. They need to realise how much space is available across Australia and how much energy could be produced,” he says. 

“There are a lot more spaces that could potentially be converted. And given the electric vehicle numbers coming into the market now, we believe it will be essential to create new sources of electricity to power them.”

Six-year payback period

In 2022, the French Senate passed a law requiring car parks with 80-400 spaces to install solar shades, a move that could deliver the equivalent of an estimated 13 nuclear power plants. 

The concept of solar car parks has not been completely ignored in Australia. 

The idea took off about five years ago and interest has doubled year-on-year ever since, estimates Smart Commercial Solar managing director Huon Hoogesteger. 

Just a few examples are the massive 5.8 MW solar system installed in the Elizabeth City Centre, while the Castle Plaza shopping centre has installed 2.2 MW of carpark solar. Both projects are in Adelaide and have been run by retail asset manager Vicinity Centres.

The Chadstone shopping centre in Melbourne has a 1.6 MW array.

And the country is not short on companies ready to install the tech needed. 

Canyon Solar has fitted out five sites already, totalling almost 1 MW, and Smart Commercial Solar is about the same and is about to add another 250 kilowatt (kW) shopping centre car park in Queensland. Solar Car Parks and PV Structures are also in the mix. 

Solar car parks cost about 30 per cent more than using stretch fabric as shading but the investment pays off in six years from the energy generated, says Hoogesteger. 

“There’s also a measurable uplift in revenue created by having covered car parks. I believe it’s around about 2 per cent so it’s quite significant,” he told Renew Economy.

“Customers are more likely to stop and they’re more likely to stay longer, and solar car parks attract EV drivers like moths to a light.”

His company uses bifacial panels which means there is glass on both sides to benefit from the albedo effect, essentially allowing a panel to create electricity from the light waves reflecting off the ground. This creates an architectural value to the site as well, drawing people in. 

“Car park solar solves a couple of problems. Structural issues on roofs are constantly an issue for big buildings such as shopping centres. The number of obstructions up there are also problematic. So by bringing the panels into an open area, providing those benefits of amenity, charging, lighting and an architectural bonus as well, it all adds up to a very attractive offer.”

He says prices are coming down for solar car parks and installation times are getting faster, with the 250 kW Queensland site being deployed in six weeks.