Fastest 1MW+ Rooftop Solar Installation in Australia

Feasibility

During March of 2022, Beam Solar assisted one of their clients with the assessment and procurement for a 1.2MW rooftop solar array at their Victorian facility. Little did they know at the time, this system would become the quickest megawatt-scale single-site rooftop solar installation in Australia.

The proposed rooftops were well suited to solar install, with small roof slopes, large wide areas, minimal obstructions, and several options for access. However, on the electrical side, the system wasn't straight forward. The electrical infrastructure for the site meant that the solar array would need to be split into two, with seperate inverter stations, Network Protection Units (NPUs) and electrical connection points. All of this detail was provided by Beam in the brief when the project was taken to market.

In addition, due to tax write-off reasons, the client needed the project to achieve PC by June 30. Beam made sure to include this requirement in the brief, paired with a hefty Liquidated Damages (LDs) clause to ensure the business case for the project would be upheld. When it came to assessing the offers received, this requirement would be the most difficult for the solar retailers to meet.

Contract Execution

The offers rounds were hotly contested. Ten different solar retailers made compelling bids on the project. However, only two had agreed to the tight timeline and LD's, while still meeting all other design requirements. Through contract review and discussions, Beam was able to differentiate the two solar retailers, and determined who was capable and willing to deliver the project at record pace.

On April 20th 2022, just over two months before the planned PC date, the Solar PV Design & Construct contract was signed by both parties.

• April 20th 2022 - Contract Execution

For reference, a standard 1MW rooftop solar system is expected to take somewhere between four and six months to achieve Practical Completion from contract execution. This placed the deadline on this project at less than half the typical timeline. In other words, things had to move quickly.

Implementation

The first stage of a solar installation involves producing detailed engineering designs to facilitate product procurement and lodgement of the DNSP grid application. This process generally takes a few weeks. With the completed detailed design pack and construction plan for this project being put together over a single weekend, the pace had been set early.

Those with experience in commercial solar install would note that the structural certificate for the roof-mount system is also typically completing during this stage of the project. However, in this case a structural certificate matching the proposed panels and layout had been completed by Beam prior to project commencement.

• April 25th 2022 - Detailed Design & Construction Plan Completed

Regarding procurement, the installer had a warehouse with much of the stock needed for the project already on hand. This allowed for an 8-12 week efficiency gain as lead-times on the key equipment for the project (solar racking, PV modules, cable tray, inverters etc.) could be avoided.

So, with detailed designs completed and signed-off, and much of the equipment located in a nearby warehouse, site mobilisation, which typically occurs 1-2 months into the project, commenced a mere 6-days from contract execution. Next came the installation works.

• April 26th 2022 - Site Mobilised

Day 1 of install - All workers were inducted to site, edge protection & skylight covers were installed and plant equipment was delivered along with the racking equipment.

Day 2 of install - The array was fully marked out and roughly 50% of the frame footings were installed on the roof.

Day 4 of install - All frame footings were installed and the solar rails began going in.

Day 10 of install - Solar rails were all installed and the install shifted to cable trays and DC string cabling.

• May 6th 2022 - Solar Racking Completed

Day 16 of install - The GEDA Solar lifter was set-up and the first of 2,667 solar panels were installed.

Day 24 of install - Roughly 50% of solar panels had been installed along with the DC string cabling and frame earthing.

Day 30 of install - Roughly 75% of all solar panels, DC array cabling and cable trays had been completed, and works on the AC side began on the first of two inverter stations. First Network Protection Unit (NPU) installed.

Day 35 of install - All solar panels had been installed, along with all string cabling to the DC disconnection point. Array DC cables back to inverter stations were underway, and works set to begin on the second inverter station.

• June 4th 2022 - Solar Panel Mounting and String Cabling Complete

Day 40 of install - All inverters had been mounted and all DC string return cables run to respective inverter station for termination.

• June 10th 2022 - All Solar Inverters Mounted

Day 48 of install - All AC cables run from solar inverters and terminated at respective NPUs. 

Day 51 of install - Second NPU crane-lifted up to install location and mounted. All AC cables installed between inverters, NPUs and connection points.

• June 23rd 2022 - Both NPUs Installed and All AC Cables Run

Day 58 of install - All tray covers installed, AC & DC cables terminated, system commissioning completed, site packed-down, cleaned-up and demobilised.

• June 30th 2022 - Practical Completion

Summary

So, this 1.2MW rooftop system was fully designed, procured, installed and commissioned over a period of 10-weeks, achieving Practical Completion by the end of the financial year, and allowing the client to claim tax write-off for the asset. This is a record pace for a single-site, megawatt-scale rooftop solar system in Australia.

• April 20th 2022 - Contract Execution
• April 26th 2022 - Site Mobilised
  
• May 6th 2022 - Solar Racking Completed
  
• June 4th 2022 - Solar Panel Mounting and String Cabling Complete
  
• June 10th 2022 - All Solar Inverters Mounted
  
• June 23rd 2022 - Both NPUs and All AC Cable Runs Installed
  
• June 30th 2022 - Practical Completion

Many factors came into play in order to achieve this impressive feat, including lightning fast mobilisation on site, a huge install team of 20+ workers, and very few wet-weather days hindering roof works. However, it was largely through the proposed deadline and LD's stipulated in the contract, as well as ongoing project management and Quality Assurance from the Beam Solar team that helped ensure that the project stayed on schedule and was delivered on time.

If you'd like to see how we can help get your commercial rooftop or ground-mount solar array assessed, designed, contracted and installed, feel free to reach out to anyone on the Beam Solar Team, or click below to start your own Solar Assessment through the Beam Solar platform. Maybe we'll even be writing about your record-breaking solar system soon enough.

References: