Sulfur hexafluoride is crucial for high-voltage equipment, but it can trap heat in the atmosphere for 1,000 years or more. And emissions are on the rise.
The power grid is underpinned by a single gas that is used to insulate a range of high-voltage equipment. The problem is, it’s also a super powerful greenhouse gas, a nightmare for climate change.
The Montreal Protocol was designed to heal the ozone layer. It may have also fended off several degrees of warming—and a collapse of forests and croplands.
Sulfur hexafluoride (or SF6) is far from the most common gas that warms the planet, contributing around 1% of warming to date—carbon dioxide and methane are much more well-known and abundant. However, like many other fluorinated gases, SF6 is especially potent: It traps about 20,000 times more energy than carbon dioxide does over the course of a century, and it can last in the atmosphere for 1,000 years or more.
Despite their relatively small contributions so far, emissions of the gas are ticking up, and the growth rate has been climbing every year. SF6 emissions in China nearly doubled between 2011 and 2021, accounting for more than half the world’s emissions of the gas.