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 voltage equipment like switchgears and circuit breakers. With the ever-growing challenges of federal & local reporting and a shift towards more eco-friendly practices, the industry is seeking ways to reduce SF₆ emissions.

One way to curb emissions is to switch to the use of reconditioned SF₆ gas instead of purchasing virgin SF₆ gas. The production of virgin SF₆ gas was outlawed in the United States with the Kyoto Protocol; therefore, virgin SF₆ gas purchased in the United States must be imported from Europe, Russia, and Asia. There is a large stockpile of SF₆ gas in the United States. From an environmental perspective, reconditioning gas helps us to lower the carbon footprint by removing the need to manufacture more SF₆ gas. The production of SF₆ is a known source of underlying emissions. According to the Environmental Science & Technology Report, SF₆ production in China contributed to 10 percent of gas emissions from the country between 1990 and 2010.

Read full article in the SPECIAL SCADA for the Smart Grid ISSUE.