CIGRE Paris - SSEN Transmission and supply chain partners celebrate rollout of “revolutionary” modular substations

25 August 2026

Over 1GW of orders in “major step forward” for efficient renewable grid connections

Image: Paul Cooley - Director of Onshore Capital Delivery, SSEN Transmission; Markus Heimbach - CEO, High Voltage Products Business Unit, Hitachi Energy; Laura Fleming - Country Managing Director for Hitachi Energy in the UK & Ireland; Rob McDonald - Managing Director, SSEN Transmission; and Christianna Logan - Director of Connections, Customers and Stakeholders, SSEN Transmission. 

At the CIGRE Paris Session global event this week, SSEN Transmission together with each of its supply partners, Hitachi Energy and GE Vernova, celebrated a milestone in placing the first orders of standardised modular substations in the north of Scotland: enabling much of the assembly, wiring, and testing to be completed off site before installation and commissioning.

By carrying out much of the construction in controlled factory environments, modular substations offer clear benefits over traditional builds. These include a standardised and repeatable design, built in safer and cleaner conditions, resulting in a smaller site footprint and less time spent on site. This reduces costs and disruption for local communities while still meeting the high safety, quality and reliability standards required for critical electricity infrastructure.

In May, SSEN Transmission awarded framework agreements to Hitachi Energy UK Limited and GE Vernova, enabling the delivery of modular substations following a year-long competitive tender process.

Since then, orders for modular substations have now been placed – 15 modules, representing over 1GW of renewable generation, will be ordered by the end of 2026 with more to follow in due course – and representatives of SSEN Transmission, Hitachi Energy and GE Vernova gathered together at CIGRE Paris Session to celebrate this progress.

Designed to operate at 132kV and 33kV, modular substations are ideally suited to smaller‑scale grid connection projects, including individual windfarms and other renewable generation.

SSEN Transmission plan to roll out the modular substation initiative across the majority of its customer connection project portfolio, with energisations set to begin from Autumn 2028.

The modular substation programme forms part of SSEN Transmission’s wider drive to innovate and modernise how grid infrastructure is delivered, supporting the connection of clean, home-grown power while helping to meet national clean power and energy security needs.

Image: Left to right: Craig Jones - Strategic Account Leader, Grid Solutions, GE Vernova; Olivier Monteil - North & South Europe Commercial & Tendering Leader, Grid Solutions, GE Vernova; Paul Cooley - Director of Onshore Capital Delivery, SSEN Transmission; Romaine Chambault - Chief Operating Officer, Grid Systems Integration, GE Vernova; Rob McDonald - Managing Director, SSEN Transmission; and Christianna Logan - Director of Connections, Customers and Stakeholders, SSEN Transmission. 

Held every two years, the CIGRE Paris Session is the world’s foremost collaborative knowledge development and sharing programme for the power system sector, attracting around 9,000 participants from more than 100 countries.

Rob McDonald, Managing Director of SSEN Transmission, said:

“I am delighted to celebrate with our supply partners this major step in the world-leading innovation we are pioneering at SSEN Transmission.

“Securing a supply of modular substations marks a revolutionary change in how we deliver customer connections. The benefits include shorter construction times and reduced environmental impact, including smaller site footprints.

"Our adoption of this new technology enables us to accelerate delivery of our ambitious £29bn investment programme in the country's energy security and clean power needs."

Markus Heimbach, CEO, High Voltage Products Business Unit at Hitachi Energy, said:

“Building a secure, resilient, and sustainable power system requires us to challenge conventional approaches and embrace innovation at scale. Advanced technologies like this mobile substation solution featuring our high-voltage SF6-free EconiQ® Gas-Insulated Switchgear can deliver tangible benefits today, while creating the flexibility needed for the grid of tomorrow. Our collaboration with SSEN Transmission is a first-of-its-kind initiative that reflects our shared commitment to enabling the UK’s clean energy transition and building the flexible infrastructure needed to support it.”

Clar Collins, Executive Managing Director North South Europe Region, Grid Systems Integration at GE Vernova, said:

"The scale of the energy transition demands a fundamental rethink of infrastructure delivery. By industrialising the substation build process, we are moving beyond traditional project cycles to a model defined by precision, speed, and reliability with a significant UK content, strengthening domestic industry. At GE Vernova, we are proud to partner with SSEN Transmission to prove that modularity is the key to unlocking the grid capacity needed to meet the UK’s ambitious clean energy targets.