SF6, or Sulphur hexafluoride, is an artificially produced gas that does not exist naturally in the atmosphere.
What is SF6?
In everyday life, the gas performs a very important role as an insulator and circuit breaker in high voltage switchgear systems, a critical part of our power infrastructure.
However, SF6 is also one of the world's most powerful greenhouse gases. Just 1kg of SF6 released into the atmosphere does as much harm as 22 tonnes of CO2 emissions! Every year, leaks and emissions of SF6 gas from energy system components do just that.
So although SF6 is the most efficient and effective safety method of stopping electricity flow in critical power infrastructure, it can be extremely harmful to the environment. We have some solutions including CO2, gas mixtures and vacuum technology, but development takes time and different solutions work best for different applications.
Even when solutions are developed for all voltage levels, switchgear typically lasts for around 40 years. It will take time for a complete shift away from SF6, so in the meantime we must educate and regulate its use.
SF6 Monitoring and Developing Alternatives
Research scientists at SINTEF Energy Research play a leading role in monitoring the emissions and coordinating work to develop alternatives to SF6 for various scenarios.
Norway's inventory (how much is in the facilities and in stock) and emissions of SF6 gas are monitored and reported every year to the Norwegian Environment Agency. The reporting is done by the User Group for gas-insulated switchgear, led by SINTEF.
SINTEF is also working to find the best environmentally friendly alternatives to SF6 so that the gas can be phased out in the long term. At present, vacuum technologies, CO2, and alternative gas mixtures are among the solutions being considered for different applications.
SINTEF also plays a role in educating decision-makers and the public about SF6. Because of misreporting in the media, many myths circulate about the gas. Research scientist Maren Istad and a team of experts from across SINTEF Energy Research and NTNU addressed some of these myths in this article.
Chief Scientist Magne Runde was invited to speak at an annual meeting of the user group on the development of alternatives to SF6. He outlined some of the major alternatives, which was followed by a panel discussion with some of the companies looking to bring the solutions to market.