What is SF₆? Why should we be monitoring it?

Subject: Environment

Section: Climate change

What is SF₆?

SF₆ is a stable colourless, odourless, synthetic fluorinated gas that makes effective insulating material for medium and high-voltage electrical installations.
Around 80% of the SF₆ used globally is in electricity transmission and distribution.
Medium- and high-voltage electrical equipment contains SF₆ to insulate the live electrical parts and to switch the flow of electrical current on and off.

A powerful Greenhouse Gas:

Sulphur hexafluoride or SF₆ is the strongest known greenhouse gas with a global warming potential of 25200 and an atmospheric lifetime of 3,200 years.
SF₆ is rapidly accumulating in the atmosphere, driven by the demand for SF₆-insulated switchgear in developing countries due to increased renewable energy installations.
SF₆ emissions occur during all stages of the component lifecycle: manufacturing, operation, and decommissioning of equipment contribute the most to the emissions of the operational phase.

Where is SF6 used?

What is the status of SF₆ in India?

SF₆ is mostly imported into India. There is a lack of publicly available data on total production, use growth rates and emissions of SF₆ in India.
India imported 600 shipments from China, Taiwan and the United States and is the largest importer of SF₆ in the world.
In developed countries, SF₆ is regularly monitored to immediately detect any SF₆ leakages, on an almost real-time basis while India still needs to make a lot of progress in SF₆ handling and monitoring.
The maximum threshold for leakage of SF6 is 0.5 per cent per year.
There is currently no regulatory framework to monitor, report and manage SF₆ in India and the country needs to develop a framework for SF₆ monitoring, reporting and phase out.

What are the international regulations on SF₆?

The U.S. Environmental Protection Agency (EPA) made mandatory the reporting of large SF₆ emissions in 2009.
In Europe, it is also mandatory to recycle, reclaim or destroy the SF₆ gas contained in electrical equipment.
There are no SF₆ regulations in Asia that focus directly on transmission and distribution operators.
Japan’s switchgear OEMs and electric utilities created a voluntary action plan in the late 1990s and reported a substantial reduction in reduction in SF₆.
In 2015 South Korea implemented a GHG Emissions Trading Scheme, which includes SF₆.
China has also made moves away from SF₆.

What are the alternatives to SF₆?

Use of clean air, hydrogen, nitrogen, etc is being considered but these are available mostly for medium voltage (MV) switchgear.