ABB has achieved a significant breakthrough in switchgear technology with the development of a solution that deploys a new insulation gas mixture as a substitute for sulfur hexafluoride (SF6).
This alternate gas mixture has similar insulation properties as SF6 gas now used in switchgear, but can substantially lower environmental impact due to its extremely low global warming potential. ABB’s gas-insulated switchgear (GIS) with the new gas mixture has the potential to lower carbon dioxide equivalent emissions by up to 50 percent through the lifecycle of the equipment, compared to its predecessor with the same rating.
“This is a significant achievement and can pave the way for more eco-efficient switchgear in the years ahead,” said Bernhard Jucker, Head of ABB’s Power Products division. “It will enable our customers to lower environmental impact and is very much in line with ABB’s ongoing commitment to technology and innovation to enable power and productivity for a better world.”
For decades, SF6 gas has been used extensively in the electrical industry for dielectric insulation and current interruption due to its physical properties. Pressurized SF6 gas aids the safe and reliable operation of gas-insulated switchgear because it has a much higher dielectric strength than other insulation media, making it possible to significantly reduce the size of switchgear installations and enable installation in areas where space is at a premium. However, SF6 is a known greenhouse gas and moreover, its lifecycle management requires careful handling for utility and industrial users. The cost of managing it in a compliant manner can also be substantial, particularly when decommissioning aging substations.
The new technology will be deployed for the first time at a substation located in Oerlikon, Zürich, as a pilot installation for the leading Swiss utility, ewz. In addition to the 170-kV high-voltage GIS, ABB will also install medium voltage GIS with the new gas mixture.
In a power system, switchgear is used to control, protect and isolate electrical equipment to boost the reliability of the electrical supply. With GIS technology, key components including contacts and conductors are protected with insulating gas. Compactness, reliability and robustness make it a preferred solution in urban areas and other places where space is a constraint or in harsh environmental conditions.