Darwin International Airport Solar Farm - case study

Northern Territory Airports (NTA) owns Darwin International and Alice Springs Airports in the Northern Territory. 

Darwin International Airport is the 10th busiest airport in Australia. Over 2 million passengers travelled through the airport in 2017 across more than 27,000 flights.

The challenge

Recent expansion at Darwin International Airport (DIA) has greatly increased electricity use, and accompanying overheads.

In a bid to reduce long-term power costs, the NTA turned to renewables and UGL.

UGL was engaged to implement a solar energy-generating system, with key objectives including:

• reducing the long-term costs associated with the airport’s power requirements
• providing a Solar Photovoltaic (PV) system with the highest system reliability
• delivering the project on schedule and within budget
• causing zero disruptions to airport operations during construction

Our solution

UGL provided the design, supply and construction services for the PV generation plant. Stage 1    was 4MW located beside the main runway, utilising land that was forecast to be used towards the end of the airports 25-year plan. This provided an ideal use of land in the meantime, gaining the off set in power consumption for the airport. Working airside proposed challenges that were unique to the environment.

UGL brings the following expertise to the project:

• project management
• design management
• design services
• construction management
• health and safety management
• environmental management
• community and stakeholder relations
• incident management

The project’s scope included the complete design, supply, installation, testing and commissioning of the PV generation system connected to the local ring main system.

The project incorporated the following equipment:

• main 11kV PV switchboard comprising:
  • two feeder bays for connection into the existing DIA 11kV ring main system
  • four bays for TR-1, TR-2, TR-3 and TR-4 11/0.433kV transformer connections
  • two bus sections with one bus-section circuit breaker
• four outdoor 11/0.433kV kiosk transformers rated at 1MVA
• four 415V sub-array switchboards SSB-1, SSB-2, SSB-3 and SSB-4
• sixty SMA STP 60 string inverters
• fifteen thousand (15,095) Hanwah Q-Cells 265W PV modules generating 3.975MWdc
• fixed array PV module racking
• driven piles to support PV module racking
• 1000V DC cabling reticulation
• 11kV and 415V AC cabling reticulation
• associated protection, control, metering and communications equipment
• lightning protection system (OHEW)
• earth grid and
• site fencing

Key successes

Working airside also provided several interesting challenges that are not standard construction site items. The runway was used by commercial and RAAF fighter jets, so consideration had to be given to the level of hearing protection.

It was also essential that the project did not increase the bird activity in the area as that would be hazardous to the planes and cause interruptions to flight schedules. The risk assessment was interesting to conduct for the bulk earth works, minimising the amount of disturbed ground at any one time.