Hitachi Energy and National Grid have successfully energised a pilot project replacing SF6 in installed high-voltage gas-insulated lines with an eco-efficient fluoronitrile based gas mixture. This retrofill solution, in Richborough, UK, is part of Hitachi Energy's EconiQ portfolio which is designed to deliver a better environmental performance when compared to conventional solutions. 

National Grid is one of the world’s largest investor-owned transmission and distribution utilities. It has an ambition to remove all SF6 from its fleet by 2050. 

In this pioneering project, National Grid has replaced SF6 from 420 kV gas-insulated lines installed in 2016, removing 755 kg of the gas. 

Although SF6 has been used in the electrical industry for decades, owing to its excellent insulation and current interruption properties, it has a high ‘global warming potential index, GWP, and requires careful handling to prevent escape. 

Markus Heimbach, managing director of the High Voltage Products business in Hitachi Energy, commented: "… [our] EconiQ retrofill technology for installed gas-insulated lines along with the new EconiQ switchgear and breakers portfolio will enable our customers and the industry as a whole to reduce carbon footprint and rapidly transition to eco-efficient solutions." 

"The retrofill solution replaces SF6 [with an eco-efficient gas mixture], cutting emissions and network outages at the same time as saving costs by avoiding the need to spend on … replacement equipment," said Chris Bennett, acting president of National Grid.” 

EconiQ is Hitachi Energy's eco-efficient portfolio for sustainability, where products, services and solutions are proven to deliver exceptional environmental performance. Recently, the company announced the acceleration of its development of eco-efficient solutions, outlining its EconiQ roadmapof switchgear and breakers in various voltage levels.