Abstract :
Summary form only as given. Concerns have been expressed in recent years over the relatively large quantities of SF6 detected during high level atmospheric balloon measurements. SF6 has been used in electrical power equipment for the last 20 years or so and is the only major insulant and interrupting media now used in EHV transmission switchgear. For this reason, engineers worldwide became concerned about environmental pressures and the satisfactory continued service use of SF6 in HV electrical equipment. The subject was passed to CIGRE for investigation, CIGRE being a worldwide organisation representing the electric power industry. Work started with CIGRE Working Group 23-Substations in the 1990s and has continued ever since. Two major reports have been issued, the first being “SF6 and the Global Atmosphere”. This report demonstrated that SF6 was a significant greenhouse gas but although quantities in the atmosphere were in fact very small in terms of its effect on global warming, it was nevertheless necessary to no longer deliberately release SF6 into the atmosphere and improved handling procedures were required. To satisfy this need, a further document entitled “SF6 Recycling Guide-Re-use of SF6 in Electrical Power Equipment and Final Disposal” was subsequently issued giving guidance on handling procedures. Further work is now ensuing to establish the SF6 global balance and to examine procedures to be applied for handling SF 6 mixtures with other gases
