“Sulphur hexafluoride has a global warming potential of roughly 23,000 times that of CO2.”
PhD candidate Dennis van der Born will obtain his doctorate on 11 April, with his thesis “Dielectric Coatings for High-Voltage Gas-Insulated Switchgear”. He did his research within the DC systems, Energy Conversion & Storage group and was supervised by Johan Smit.
Dennis: “The electric high-voltage grid and its switching stations take a lot of space, which is a problem in areas with a high population density – especially because of the increasing energy consumption. To save space, electrical substations can be placed in tubes with insulating gas. The gas that is currently used, sulphur hexafluoride, has a global warming potential of roughly 23,000 times that of CO2. This has resulted in strict regulations for the use of this gas. Industry would like to get rid of this gas, but alternative gasses result in a lower voltage level. To avoid bigger installations and decreasing voltage levels, a new gas should be found. Another possibility is applying a coating on the currently rough metals. I have done research into the feasibility and composition of the coating layer. The research has shown that an improvement of 40% is possible, but the coating can also have a negative effect on the voltage level. Also, I have worked on a computer model which can predict at which voltage and at which place a switching installation will break. There are several subjects that require further research, such as upscaling and the long-term usage. This research is necessary in order to apply coating in a reliable way.“