Transpower undertook several vital upgrades to support the increased energy demand and facilitate Mataura Valley Milk’s transition to renewable energy. These included replacing two aging single-phase 110kV/33kV transformer sets with new 80 MVA units and adding two new 33kV feeder panels to the existing GHA switchboard specifically for this supply. PowerNet, an electricity network management organisation in the South Island, also upgraded its 33kV network to connect to the Mataura Valley Milk plant through its McNab substation.
The successful commissioning of the 15MW electrode boiler was crucial to secure the GIDI Fund contribution, requiring completion by September 2023. At the same time, Transpower’s upgrade works in Gore had to be finished by July 2023 to allow adequate time for downstream commissioning by PowerNet and Mataura Valley Milk.
Our involvement:
AECOM provided a range of services to facilitate the smooth execution of the upgrades. They began by developing a comprehensive concept design with multiple options, swiftly leading to the selection of the most suitable layout. AECOM then proceeded to deliver the design in four stages or packages: enabling works, civil and structural, transformer installation, and 33kV switchgear installation. This strategic approach allowed for the early ordering of transformers and the construction of transformer foundations while simultaneously finalising the protection design.
Mataura Valley Milk and the regional electricity network substantially benefited from AECOM’s involvement. First and foremost, the outdated single-phase transformers were replaced with modern three-phase units, resulting in improved overall network efficiency. Adding spare capacity to the 33kV switchgear ensured greater flexibility and reliability in power distribution. The project, which converted industrial process heat fuel from coal to electricity, is an example of the low-emissions, electrified future that Transpower’s national electricity transmission system can enable. Lastly, the upgrade also facilitated the Kaiwera Downs Windfarm to connect to the grid, providing more renewable electricity to power our country. .
The collaborative efforts between Mataura Valley Milk, Transpower, PowerNet, and AECOM, meant this ambitious electrification and energy efficiency upgrade was completed within a tight timeline of 19 months. As part of the GIDI fund, the project is a significant milestone in New Zealand’s journey towards a sustainable energy future.