New Zealand’s largest— and only floating – solar array has officially opened at the Rosedale Wastewater Treatment Plant. It is hailed as a “landmark system” which “signals an important milestone for solar in New Zealand”.
The one-megawatt array covers one hectare, consists of more than 2,700 solar panels and 4,000 floating pontoons, and will generate 1,486MWh per year. This is enough electricity to power a quarter of the total energy needed at the treatment plant.
Auckland Mayor Phil Goff said: “Large solar installations like this are common overseas, and it’s good to see we are now making use of the technology in New Zealand. The one-hectare array will reduce carbon emissions by 145 tonnes each year, helping us achieve our climate change goals and making our city cleaner and more sustainable. It will generate enough power to run the equivalent of 200 average New Zealand homes for a year.”
The array was built by Vector Powersmart over four months. First, 65 concrete ballast anchors, weighing 2.5 tonnes each were lowered into the pond before the solar panels were floated into place. Watercare chief executive Raveen Jaduram says the floating array is the latest in a series of five solar projects and will help Watercare to meet its cost savings and emissions-reductions targets: “Rosedale is one of the five most energy-efficient wastewater treatment plants in Australasia. Most of the wastewater is moved around the plant by gravity and almost all of the energy comes from biogas— a by-product of the wastewater treatment process. The array will contribute to our long-term goal of being energy neutral at the plant.”
General manager Vector Powersmart Rogier Simons said: “Given the drive to decarbonise and use cleaner forms of energy, this project is a significant milestone for New Zealand. It also demonstrates that solar solutions can be found even in challenging environments like wastewater treatment ponds.”
The electricity will be used for pumping and aeration for the natural bacteria that break down the waste as part of the treatment process.
