SSEN Transmission leads rollout of “revolutionary” modular substations for grid connections
11 May 2026
Image: Modular substations are ideally suited to smaller‑scale grid connection projects, including individual windfarms and other renewable generation (credit: GE Vernova)
Our new approach to substation delivery is leading the way, with standardised modular substations that enable much of the assembly, wiring, and testing to be completed off site before installation and commissioning.
Designed to operate at 132kV and 33kV, the modular substations are ideally suited to smaller‑scale grid connection projects, including individual windfarms and other renewable generation.
Learn more in the following video.
We are now rolling out the modular substation programme across a large portion of our customer connection projects, with energisations beginning from Autumn 2028.
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.
We have awarded a major framework agreement to Hitachi Energy UK Limited and GE Vernova, enabling the delivery of modular substations following a year-long competitive tender process.
Image: A modular substation (credit: Hitachi Energy)
Rob McDonald, Managing Director of SSEN Transmission, said:
“Modular substations represent a revolutionary change in how we deliver customer connections, and SSEN Transmission is at the forefront of rolling this technology out across our network.
By doing more of the work off‑site, we can improve safety, shorten construction times and significantly reduce the environmental impact of construction, including smaller site footprints and less disruption for local communities.
Working collaboratively with our supply chain is central to that approach, and we’re actively exploring opportunities that could help support skilled jobs and build technical expertise here in Scotland.”
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 ambitions.
Markus Heimbach, CEO, High Voltage Products business unit, from Hitachi Energy UK Ltd, said:
“In today’s environment, critical infrastructure has to do more than perform, it has to endure. The Integrated GIS Assembly is designed with that reality in mind.
By enclosing EconiQ® gas-insulated switchgear (GIS) within a robust, containerised structure, the IGA protects vital assets from the elements, from interference, and from deliberate damage, while maintaining exceptional reliability. EconiQ SF6-free technology is as reliable and scalable as the conventional solution and delivers the lowest carbon footprint. It allows substations to be delivered as complete, tested systems, ready to operate safely and securely.
This approach gives network operators greater resilience, faster recovery and confidence that their infrastructure can continue to serve communities even during periods of disruption and uncertainty.”
Clar Collins, Executive Managing Director North South Europe Region, Grid Systems Integration at GE Vernova, said:
“We’re honoured to have been chosen by SSEN Transmission for this important modular substation programme. By combining modular delivery with GE Vernova’s g³ technology, part of our GRiDEATM SF₆ free solution portfolio, this programme is designed to provide faster, lower-impact renewable grid connections, with more of the work completed off site before installation, while supporting cleaner energy.
We look forward to working in close collaboration with SSEN Transmission to help deliver sustainable and reliable grid infrastructure that supports Scotland’s renewable energy ambitions and strengthens energy security,”