Omnia Projects supported National Grid in the installation of a new shunt reactor at Rowdown 400kV Substation, delivered under National Grid’s self-delivery model. Under this model, National Grid directly manages the delivery of the works, with specialist partners providing targeted technical support.
We were appointed to provide Site Management and Temporary Works services, helping to ensure the safe planning and execution of one of the most technically challenging elements of the project: the delivery and installation of a new 400kV Royal SMIT shunt reactor.
The Challenge
The installation of the new shunt reactor presented a number of logistical and engineering challenges.
The area identified for the new reactor bund was constrained by surrounding infrastructure, including existing high-voltage cable troughs running across the substation. In addition, there were space constraints within the substation meaning conventional delivery and lifting methods were not viable.
Our Solution
To overcome these challenges, the shunt reactor was first delivered to site and transferred onto a Self-Propelled Modular Transporter (SPMT).
The first step was the installation of an appropriately-rated overbridge to span the existing cable troughs. This allowed the SPMT carrying the 131 tonne reactor tank to be carefully manoeuvred across the substation, enabling the equipment to traverse the constrained access routes without imposing unacceptable loads on existing infrastructure.
Once the reactor reached its final location adjacent to the newly constructed bund, a gantry crane system was erected to undertake the final lifting operation. The gantry allowed the reactor to be precisely lifted and lowered into position within the restricted working area where a conventional jack and skid operation could not be performed.
This method provided a controlled and safe solution to a highly constrained installation.
Temporary Works Management
Given the complexity of the heavy transport and lifting operation, robust temporary works management was critical to the success of the project. Omnia Projects’ Temporary Works Coordinator was responsible for overseeing the entire temporary works process, including:
- Coordination of temporary works design
- Review and approval of method statements and lift plans
- Ensuring compliance with temporary works procedures and standards
- Coordination between National Grid, specialist contractors and designers
- Managing inspections and hold points during the operation
This structured approach ensured that all temporary works elements associated with the transport and lifting operations were properly designed, checked, and executed safely.
Collaborative Delivery
The success of the reactor installation was achieved through close collaboration between National Grid, Omnia Projects, and specialist contractors.
Heavy transport and specialist lifting experts Allelys Heavy Haulage played a key role in delivering the complex site operation. Their experience with SPMT operations and gantry lifting systems ensured the move was carried out safely and efficiently within the constrained substation environment
Outcome
Through careful planning, engineering innovation, and strong collaboration between project partners, the new shunt reactor was successfully transported across the substation and installed within the new bund location.
The project demonstrates how specialist temporary works management, detailed planning, and advanced heavy transport techniques can enable complex infrastructure installations to be delivered safely within operational transmission environments.
Omnia Projects is proud to have supported National Grid on this challenging installation and to continue playing a role in delivering critical infrastructure upgrades across the UK transmission network.