Cradle-to-gate life cycle assessment comparison between two switchgear designs: Eliminating SF6 gas under European legislation

Abstract

Due to recent changes in European regulations and pressure to reduce emissions in the energy sector, secondary distribution boards have been going through structural and functional modifications by manufacturers to reduce and even eliminate the use of sulphur hexafluoride (SF₆). This inert gas has a high global warming potential and is commonly used in this equipment for insulation. The present study was carried out to compare the environmental performance of two switchgear models from a cradle-to-gate and use perspective. The new design (neoGEN model), which does not use SF₆, was compared with the previous model (FluoFix). The environmental performance of these models was compared through life cycle assessment methodology, using ReCiPe 2016 at the midpoint and endpoint level, analysing all categories included in this method. The assessment focused on the production stages located in Portugal but also included the transport to the final customer and the use stage (the release of SF₆). The results of the production stage show that the FluoFix model has 5 % more environmental impacts than neoGEN due to the copper and stainless steel used in the structure at an endpoint level. On a midpoint level, the results show some gains in the analysed categories, displaying a higher reduction in global warming potential (19 %) and stratospheric ozone depletion (64 %) categories. Finally, the assessment of the use stage considered scenarios in which the equipment would have a potential leakage between 7 % and 22 % (best case scenario) and between 15,7 % and 41 % (worst case scenario). This analysis demonstrated that in a scenario where leakages are minimal, the use of neoGEN shows a 74 % reduction in the global warming potential category. For future work, designers should focus on finding new materials that can replace or reduce copper and steel in the switchgear structure to reduce the environmental impact of this equipment and avoid the use of SF₆ gas.