National Grid energises substation after removing SF6   

National Grid has energised its Littlebrook substation in Kent after replacing the old infrastructure with SF6-free solutions across the site.

The new substation will enable 2GW of low carbon and renewable energy to power around 1.5 million homes.

Work on the substation included the installation of underground cabling, overhead line connections and GE switchgear.

Four existing super grid transformers have also been moved from the old substation to the new one, alongside a brand-new transformer.

Work was carried out by contractors Balfour Beatty and GE Vernova’s Grid Solutions. According to National Grid 5.6 tonnes of SF₆ gas has been saved by using GE Vernova Grid Solutions’ g3 gas-insulated busbar equipment which is SF₆ – free.

Sulphur hexafluoride, known as SF6, is the most potent greenhouse gas in existence but it plays a vital, and often irreplaceable, role in insulating switchgear on the electricity network.

Laura Mulcahy, senior project manager for National Grid Electricity Transmission, said: “We are delighted the new Littlebrook substation is now fully energised and connected to our network.

“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.”

National Grid’s ambition is to reduce its SF₆ emissions by 50% by 2030 and removing all SF₆ gas from electrical assets by 2050.

Mark Wilson, head of service, UK & Ireland at GE Vernova’s Grid Solutions business added: “National Grid has been a leader in removing SF6 from its network. They energised 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.”

Earlier this year, Utility Week looked at the work that was being done to reduce SF6, and asked industry experts if electricity networks are doing enough.