Mother Nature has been out in force!
Meteorologists were calling what came through the Waiotahe Valley last week an ‘atmospheric river’; a significant weather phenomenon linked to extreme rainfall. Widespread flooding inundated the valley, closing local roads and causing havoc for the community.
In the heart of it sat our solar farm, Te Herenga o Te Rā.
Despite the rapid escalation of water levels, it was a huge relief that our site crew and members of the community caught in the flooding remained safe, and the equipment performed as it was designed to do.
When Lodestone set out to build Te Herenga o Te Rā solar farm in the sunny Bay of Plenty valley, our engineers knew that to harvest this great solar resource, our farm would have to be able to handle a lot of water from time to time, and this week was the ultimate test!
Some say this event was more rainfall than the flooding of 2004, when residents in the valley were last reminded how quickly the water can overwhelm the area.
Anticipating extreme weather conditions like this one requires painstaking reviews of every rise and dip in the terrain, and all the rainfall that has occurred in the area for as long as records have been kept. The insights and scenario modelling have underpinned our engineering approach – a special piling design going more than 4 meters deep and extra high solar PV tables are just the start.
Considerations for rapid water flow, the possibility of floating debris, and the prospect of sliding embankments were also built into the equation. Given how quickly the rain can come, the ability to stow the panels in a horizontal position from Lodestone’s remote control centre ultimately became a critical part of bracing for this amazing force of nature.
In the end, while more costly than an average solar farm, raising the inverter stations and panel connection boxes high above the ground so the plant could continue to operate in more than a meter of water turned out to be the right choice.
The farm remained fully operational until the last few millimetres of rain came down, when the operations team decided, out of caution, to disconnect from the grid and ride out the storm.
When the sun rose again, the water receded nearly as quickly as it came. The Lodestone team were able to quickly assess the site with thermal-camera drones, scanning each component and determining just how well the tracking solar technology and flood-mitigation design met the challenge.
The team discovered that the flood waters rose to levels designed for and the farm performed as the engineering team had expected – the farm fared well!
After a big effort from the #NewPower and #Lodestone crew, who have been working hard over the weekend to complete inspections and testing, we’ve been able to recommence generation. We are once again harvesting the sunshine of Waiotahe Valley.
The Lodestone management team would like to thank all of those dedicated individuals who, while staying safe, put in the mahi to expertly deal with this unusual and isolated event.
To friends and neighbours in the Valley, Lodestone sincerely hopes that your farms and houses will rebound quickly, too. We want to give a special shout-out to the local council staff and roading crews who put in a round-the-clock effort to get the roads open again.
Finally, it would be remiss if we didn’t acknowledge the engineers who did the upfront work, planned for this type of event and got it right!
More information: https://www.linkedin.com/pulse/mother-nature-has-been-out-force-lodestoneenergy-j5mkc
