Electricity Today T&D Magazine

When it comes to medium and high voltage circuit breakers, there is no better electrical insulator than sulfur hexafluoride (SF₆). The manufactured gas is most commonly used to fill circuit breakers within utility substations to prevent and quench arcing events. SF₆'s impeccable dielectric strength, arc quenching capabilities and ability to remain thermally stable are just a few reasons why this gas has remained a staple in the transmission and distribution (T&D) industry. It has been the preferred gas in switchgear for over 50 years.

Unfortunately, the same properties that make SF₆ such a great insulating gas also make SF₆ the most potent of all greenhouse gases. One molecule of SF₆ gas can trap 23,900 times more heat than carbon dioxide over a 100-year period and remains in the atmosphere for thousands of years. About 80% of manufactured SF₆ is used in high...