Reducing the climate impact of fluorinated gases
Martin Sweeney, global head of product management at Lucy Electric, discusses the race to eliminate SF6 gases.
For years, SF6 has provided an efficient and safe means of insulating medium and high-voltage switchgear, but its potency as a greenhouse gas means it’s on the way out. The EU has long been concerned about the climate impact of fluorinated gases (F-gases) like SF6, which are greenhouse gases that trap heat in the atmosphere and contribute to climate change. The 1997 Kyoto Protocol implemented the objective to reduce the emissions of these greenhouse gases.
As a result, the EU has banned the use of sulfur hexafluoride (SF6) in new medium-voltage switchgear from January 2026. The ban is part of a gradual phase-out program that was agreed to by the European Council and Parliament in late 2023. In Britain, we’re expecting similar measures to be adopted by the government.
SF6 is widely used in medium and high-voltage switchgear for good reason. Its high dielectric strength makes it possible to create smaller ring mains units. It enabled the replacement of carcinogenic compounds used in oil-filled circuit breakers. And SF6 can interrupt large current loads, making it great for high-voltage applications.
Unfortunately, SF6 is some 22,800 times more potent than carbon dioxide over a 100-year period. That’s as measured by Global Warming Potential (GWP), which ranks gases according to their ability to trap heat in the atmosphere.
Sulphur hexafluoride is a high GWP gas because for a given mass, it traps substantially more heat than CO2. It also lasts much longer in the atmosphere than some major greenhouse gases (methane, for example has a lifetime of 12 years, versus 3,200 years for SF6).
Although volumes of SF6 in the atmosphere are tiny compared to CO2 (three parts per trillion versus 421 parts per million for carbon dioxide in 2022), they have been rising since the 1980s. That means pressure is on to phase out SF6.
Over the last few years, a race to create ring main units that employ technology other than SF6, has been going on behind the scenes as businesses move quickly to innovate. Lucy Electric’s engineers have been combining our collective experience and collaborating with our customers to come up with the solution the market requires.
After four years of hard work, we proudly launched Sabre EcoTec earlier this year, using synthetic air, paving the way for grid operators to reduce the emissions of running infrastructure as part of delivering Net Zero ambitions. The launch followed years of feasibility and close working with customers to inform the requirements of this key part of the medium voltage network.
Our solution to the SF6 problem has been to use nothing more harmful than air itself, in fact synthetic air, which guarantees the purity of the insulating gas. Thanks to intelligent design, we’ve been able to keep the benefits of the original Sabre product in terms of size, application, and functionality– but with zero global warming potential. In fact, as we are using bottled air, the dielectric material in the Sabre EcoTec is purer than the air we breathe.
We don’t use a lot of SF6, we don’t leak a lot of SF6, and technically it’s easier for us to replace it and dispose of it responsibly. But the entire electricity industry including our supply chain is determined to reduce its impact on the environment, and we expect not only the UK but also many countries around the world to ban or mandate the phasing out of SF6 from switchgear. In fact, some of our customers in the developing world are among the early adopters of SF6-free technology.
The removal of SF6 is just one part of a much wider sustainability overhaul of the grid supply chain at Lucy Electric that has seen us reduce the carbon intensity of our operations, a key metric that assesses the efficiency of our emissions in relation to our economic activities. In 2023, the carbon intensity of our operations decreased by 13.6% from the previous year, which is why we can say with confidence we’re heading in the right direction when it comes to combating global warming.
