National Grid, in collaboration with contractors Balfour Beatty and GE Vernova's Grid Solutions, has announced the successful commissioning of a new substation in Dartford, Kent, poised to augment low carbon and renewable energy capacity, serving approximately 1.5 million homes.
The project, initiated in June 2019 to replace the existing Littlebrook 400kV substation, reached completion, underlining efforts to curtail the use of sulphur hexafluoride (SF₆), a gas integral to electrical industry safety practices. National Grid emphasized the importance of this milestone in enhancing network reliability while reducing environmental impact.
Laura Mulcahy, senior project manager for National Grid Electricity Transmission, expressed gratitude for the collective effort, noting the team's resilience in overcoming engineering challenges. She stated, “Getting Littlebrook completed is a huge achievement for the team. We've had to overcome some difficult engineering and programme challenges along the way, and so to reach this milestone is a real testament to the commitment and strong relationships of everyone involved. I send my sincere thanks out to them all.”
The project encompassed intricate engineering tasks, including the installation of underground cabling, overhead line connections, and GE switchgear—essential components for controlling and protecting electrical equipment. Furthermore, the relocation of four existing super grid transformers and the introduction of a new transformer underscored the project's scale and complexity.
Mark Wilson, head of service, UK & Ireland at GE Vernova's grid solutions business, commended National Grid's dedication to SF₆ reduction, stating, “National Grid has been a leader in removing SF6 from its network. They energized our very first g3 product at their Sellindge substation in 2016. We are very proud to continue contributing towards National Grid's ambition to remove SF6 entirely by 2050 and to be part of the Littlebrook substation project, saving 5.6 tonnes of SF6 from the network. This project represents the latest vote of confidence in GE Vernova's SF6-free products which deliver the same performance and product footprint as traditional SF6 equipment, while delivering a 99% reduction in the gas contribution to global warming.”
The project's sustainability efforts were highlighted through the adoption of net zero construction methods, including the use of locally manufactured steel, solar-powered electrics, electric vehicle charging points, and biodiversity initiatives, resulting in significant emissions savings during construction.
