Benefits of proper SF6 handling to reduce SF6 emissions for sustainable Electricity Transmission and Distribution

Technologies depending on Sulphur hexafluoride, as an insulation and current breaking medium, are used in high and medium voltage switchgear. Sulphur hexafluoride (SF₆) has a number of attractive properties for current breaking. It is a superior dielectric medium, it has very good arc-switching properties and it is chemically inert, non-toxic and non-flammable. On the other hand, SF₆ has a global warming potential of 22.800 compared to CO₂, and is one of the gases listed by the Kyoto Protocol to be monitored. Nevertheless, due to its very low concentration in the atmosphere, its contribution to anthropogenic warming is very low. Unfortunately, a functionally equivalent alternative to SF₆ as an insulating and arc extinguishing medium does not exist. Aware of this, the European electrical industry represented by the T&D Europe manufacturers association has reinforced its actions in different directions to drastically reduce SF₆ emissions. These actions are applied all along the life cycle of SF₆, from procurement, production, design and manufacturing of electrical switchgear, operational life in grids, where tightness is critical and at end of life treatment. In some countries, all involved parties have signed voluntary agreements with their local Environmental Protection Agencies, committing to apply measures for effective SF₆ emissions reductions Documentation and standardization aspects as well as legal aspects are now available and consistent to properly manage SF₆ in the electrical industry. The general IEC standardization process - based on CIGRÉ papers [7], [22], [20] - has already introduced requirements covering SF₆ since 1970. It is regularly updated to include the latest improvements in best available techniques. For example the current technical report IEC/TR 62271-303 is going to become an international standard (IEC 62271-4) to enable it to b- used more widely and possibly to be referenced in some regulations. In the meantime, many regulations have been put in place, all over the world, with the same objective. For example, the European Regulation 842/2006 that regulates certain fluorinated greenhouse gases demands SF₆ recovery by certified personnel; dedicated labelling of SF₆ filled electrical equipment and reporting of some SF₆ data. Thanks to these best available practices, it is now proven by an international study that applying them on a worldwide basis can lead to significant SF₆ emissions reductions, to a much lower level than the current international hypothesis. So, everything is ready to use SF₆ electrical switchgear for a sustainable Electricity Transmission and Distribution System.