CEC Solar Awards WINNER

Karratha Shopping Centre, Karratha, Western Australia

CATEGORY: Over 240kW

Dylan Palmer of Solgen Energy Group, Ashley Funnell of AGF Electrical and Nelson Steer of ACE Electrical

Karratha may be home to fewer than 30,000 people but the economic significance of The Pilbara region that surrounds it is hard to ignore. Never forget that iron ore is Australia’s number one export! But Western Australia is also rich in sunshine and the owners of the Karratha Shopping Centre recruited Solgen Energy Group to design a PV system that would help them harness some of it.

The weather can be volatile around The Pilbara and the designers had to deliver a system that could stand up to extreme high winds, the main issue being the wind pressure under the panels. Solgen Energy Group combatted this by installing custom-designed metal wind deflectors around each array bank to minimise the possibility of wind getting under the panels, causing the pressure difference.

“We then had to combat other aspects of the high winds by using strong screws into the roof, a metallic lattice of racking and large-gauge solar rails to attach the panels to the roof,” says Solgen Energy Group senior project engineer Dylan Palmer.

“We also had issues around the edges of the building where the wind pressure was so large that this design didn’t help, so we contacted Suntech to do high pressure testing specifically for this project in order to overcome this barrier.”

Express delivery

The PV system is delivering about 40% of load for the owner.

Delivering a 2.3MW solar project anywhere is a major operation but sourcing equipment for such a remote location was a big challenge, Palmer says. “Collating and organising the materials alone was a massive undertaking. Some were shipped from China into Perth then trucked up to Karratha, other components came from Sydney and Melbourne. Very sensitive high-voltage components required vehicles equipped with special air suspension for transport from Melbourne to Karratha through some of Australia’s roughest roadways.”

The shopping centre is a great site for solar, open seven days during daylight hours, and the 2.3MW system supplies about 40% of the customer’s load. Nevertheless, local network Horizon Power agreed to allow exports and has the ability to curtail generation if the network is experiencing low consumption.

“Horizon power wasn’t used to embedded generators of this size on their network, so we had to assist them with the potential impacts and ways to deal with this type of generation,” Palmer says. “The outcome was extremely positive, and I think future large solar in the area will have many fewer barriers.”

The system was installed by AGF Electrical and ACE Electrical and features 4,617 Trina 375W modules, 1,053 Trina 380W modules, 423 Suntech 400W modules and 20 SolarEdge inverters.

At one stage during the project the team chose to avoid the extremes of daytime heat by working night shifts on the roof, which was a first for Solgen Energy Group.

The job did not include storage as local network Horizon Power “was convinced to not implement grid smoothing at this time”, Palmer says. “Solgen, in conjunction with our partner Azzo, has installed an algorithm to monitor solar production, site consumption and weather patterns to size the optimal battery, should Horizon Power come back in the future with this requirement.”