Victoria–NSW Interconnector (VNI) Project

The Victoria-NSW Interconnector (VNI) Project is a critical component of Australia's energy transformation, improving power flow between the two states of New South Wales (NSW) and Victoria and freeing up an additional 170 MW of capacity.

Jointly led by Transgrid and AEMO, the project seeks to enhance the efficiency of our electrical network, reduce congestion and strengthen grid stability. VNI increases power flow without building considerable new infrastructure by adding SmartValve technology to the 330 kV circuits at the Stockdill and Yass substations. Beca provided engineering expertise to reinforce critical infrastructure, optimise power flow and support the delivery of a more resilient, future-ready grid.

A vital step forward for Australia’s electricity grid

The VNI Project marks a vital step forward for Australia’s electricity grid, tackling the twin challenges of soaring energy demand and the growing push for renewables. Easing long-standing bottlenecks between Victoria and NSW helps power get where it’s needed, when it’s needed. At the heart of the upgrade was the installation of 15 SmartValves along the 330 kV circuits at Stockdill and Yass substations. Smart Valves technology enables the real-time control of electricity flows along power lines. The system detects areas of congestion in the network and automatically redirects flows to less congested lines.

It will help unlock spare transmission capacity, allowing more energy to be transferred between Victoria and NSW. This clever bit of engineering unlocked an extra 170 MW of capacity, without the disruption or cost of building entirely new transmission lines. Instead, it delivered a smarter, leaner solution — one that makes the grid more adaptable, more efficient and ready to handle the energy needs of the community, today and tomorrow.

A multidisciplinary approach 

Beca deployed multidisciplinary teams, which included our civil, structural, protection, secondary and primary engineers, to produce concept and detailed designs required to get the network ready for SmartValve technology. To boost grid security, we upgraded high-voltage primary plant equipment, improved protection with new relays and expanded the switch bays at both substations. Every enhancement was carefully designed to integrate with the existing system, with specific consideration to outage requirements. And, thanks to our deep understanding of Transgrid’s network and the way it operates day-to-day, we made sure every piece of the solution slotted in smoothly, safely reinforcing one of the most critical parts of the grid.

Collaboration sits at the heart of this project. From day one, Beca and Transgrid worked shoulder to shoulder — not just on paper, but out in the field with construction crews, network operators and suppliers. This open, hands-on approach meant challenges were spotted early and solved quickly, which helped keep the project on track. It also made sure the new technology was integrated effectively into a live, working network while keeping the lights on.

Delivering long term benefits

The VNI upgrade is already delivering power more smoothly and reliably between Victoria and NSW. The project has eased congestion and opened the door to more renewable energy entering the grid. On top of the technical benefits, it’s expected to deliver around AUD $268 million in economic gains and has supported over 100 local jobs. More importantly, it’s helping to build a network ready for Australia’s energy future.