Transpower New Zealand - Refreshing the grid control network for modern applications and demands

Transpower is New Zealand’s national grid owner and system operator. This state-owned enterprise is responsible for managing the flow of electricity across a high-voltage electricity transmission grid that includes 174 substations, 25,000 transmission towers and more than 12,000 kilometers of lines that run the length and breadth of New Zealand.

TransGO is Transpower’s fully converged private telecommunications network. It connects substations and sites to deliver critical management services such as protection signaling, SCADA control and communication technology services. TransGO enables Transpower to protect, monitor and control grid assets and run the wholesale electricity market in real time 24/7/365 through two national grid operating centers (NGOCs).

The introduction of new solar and wind farms to complement New Zealand’s widely sourced hydroelectric plants was driving an increase in network traffic on TransGO. Transpower needed to refresh its network to add more capacity.

Cobus Nel, Transpower’s Executive General Manager Information Services and Technology, explained the importance of TransGO to the company’s operations: “TransGO is a critical tool for Transpower to be able to move power from where it’s generated to where it’s needed, as well as being able to run the market systems that match supply and demand in real time.”

Transpower modernized TransGO about 15 years ago by moving from legacy SDH and TDM technologies to IP/MPLS and Ethernet based on Nokia equipment. The company drew on its expertise and experience with industry-proven IP technologies as it looked for solutions to refresh the network.

The winning bid was led by Spark New Zealand, the country’s largest telecommunication provider. Spark NZ partnered with Nokia to provide the IP network equipment.

Scheduled for completion in 2028, the refresh is based on Spark telecommunication services that complement Transpower’s existing fiber and microwave-based connections. The refresh will update IP/MPLS equipment with the Nokia 7250 Interconnect Router (IXR) and 7705 Service Aggregation Router (SAR) platforms and Network Services Platform (NSP) network management suite. Transpower will also undertake an architectural refresh to improve the capabilities of TransGO, including updates to its security posture, segment routing approach and Ethernet virtual private networks (EVPNs).

Spark NZ has deployed the same Nokia IP equipment and used the same IP/MPLS architecture designs in its national telecommunications network. As Mark Beder, Enterprise and Government Director at Spark, explained, “Our proposed network architecture for the project offers an innovative solution that is based on our own network design. The team that deployed our own network will support the TransGO refresh program, demonstrating our experience and expertise in operating similar network solutions in real-world environments.” 

Transpower was already comfortable with the IP/MPLS network stack and performance of the Nokia IP/MPLS platforms based on its experiences with the initial TransGO modernization project around 15 years ago.

TransGO had served Transpower well and delivered the resiliency and longevity the company needed from its critical control network. But technology had evolved and Transpower wanted to deploy capabilities that required increased speed, network silicon advancements and MPLS protocol enhancements.

The grid is also changing. Like many countries, New Zealand is accelerating renewable generation. TransGO plays an important part in providing the communications fabric to enable operational visibility and control of the new generation technologies, including solar and wind assets. This upgrade to TransGO enhances the control network so that Transpower can manage these new assets. It also provides the visibility, service segregation and strong cyber resiliency required for today and the foreseeable future.

By choosing Spark NZ and Nokia, Transpower gained access to real-world network expertise that would derisk the evolution of TransGO to a new but proven network stack.

Transpower’s history with Nokia IP routing platforms gave its network team the confidence to migrate to newer-generation routing platforms such as the Nokia 7250 IXR and 7705 SAR series. Although the platforms are new, the Service Router Operating System (SR OS) is well understood by all parties. This will ease the transition to modern IP services such as EVPN.