Smoke rises from two huge chimneys at a power plant.

A construction boom for electric power plants in countries such as China has contributed to a spike in emissions of a greenhouse gas used to insulate electrical equipment such as circuit breakers. Credit: Hu Weiguo/VCG via Getty

Climate change

Global thirst for electricity is fuelling the rise of a potent greenhouse gas

Emissions of sulfur hexafluoride soared over the 40 years to 2018, despite some countries’ efforts to curb its use.

A powerful greenhouse gas called sulfur hexafluoride is swiftly building up in the atmosphere, driven in part by the rapid growth of Asia’s electrical-power industry.

Sulfur hexafluoride is used in electrical equipment such as circuit breakers and transformers. It is the most potent of the six greenhouse gases regulated by the 1997 Kyoto Protocol: one tonne of it, released into the atmosphere, causes about 23,500 times as much warming as one tonne of carbon dioxide. The protocol requires some nations to cut their output of greenhouse gases, and many report that they have lowered their sulfur hexafluoride emissions.

Peter Simmonds at the University of Bristol, UK, and his colleagues calculated annual emissions of sulfur hexafluoride between 1978 and 2018. The researchers drew on measurements from a global network of air-monitoring sites and archived air samples.

Between 2008 and 2018, annual emissions of the gas increased by about 24% to around 9,000 tonnes a year. The rise reflects an increased demand for electrical equipment, especially in countries that are not bound by the Kyoto Protocol.