Prediction of Temperature Performance for SF6 Alternative Gas Mixtures

Sulfur hexafluoride (SF
₆
) has been the preferred dielectric gas used in electric power applications for many decades. However, SF
₆
has an extremely long atmospheric lifetime and has been recognized as a potent greenhouse gas with a very high global warming potential. One of challenges the power and energy industry faces is to reduce SF
₆
emissions and ultimately to implement alternatives in gas-filled equipment. Environmentally sustainable solutions that are both effective and low in climate impact are available for some of the applications which have traditionally used SF
₆
. Both a fluoroketone and a fluoronitrile have been successfully used in gas-insulated equipment currently operating on the grid. This paper will review these recently-implemented components of insulating gas mixtures focusing on the anticipated thermal performance in electric power applications. Results indicate that these new insulating gas mixtures can meet the temperature rise requirements for electric power equipment, providing environmentally-sustainable technology for use in gas-insulated systems as the industry makes plans for electrifying the future.