PROJECT DESCRIPTION
BACKGROUND
Transmission System Operators (TSO) transmit electrical power by operating transmission switchgears and substations, which are needed to control energy flow in the electrical network. The Circuit Breaker (CB) is the heart of a switchgear interrupting high currents safely without damage to persons or equipment. The vast majority of high voltage CB and Gas Insulated switchgear (GIS) installed the last 50 years are SF6-insulated which is the most potent GHG (GWP=24,300) currently known. While mature alternatives to SF6 are available for medium voltage applications, there are no commercially available climate neutral alternatives to SF6 with comparable performance at the 420 kV level. The LIFE Blue 420kV GIS project will demonstrate and validate for the first time an economically viable, climate-friendly and completely SF6-free 420kV GIS combining clean air insulation and vacuum CB with a digital low power instrument transformer (LPIT). This will replace an existing indoor GIS at TSO Elia in Vilvoorde, Belgium. The currently used SF6 will be replaced by natural gas consisting of nitrogen N2 and oxygen O2, called clean air (GWP=0). Besides significant GHG savings, any PFAS input is avoided (in contrast to other SF6 alternatives). In addition, the project will deliver the world's first 420kV LPIT with cast resin embedded sensors and clean air insulation (replacing conventional current and voltage transformers). The LPIT will offer new digital possibilities in current and voltage metering and additional functions e.g. for power quality measurements and will help to significantly reduce the size and copper cabling of SF6-free GIS solutions. 270 replications of the project results throughout Europe and worldwide are planned for existing GIS installations as replacements and for new substations (by 2032). Finally, the LIFE project is part of the Siemens Energy roadmap and will serve as a blueprint for technology transfer, e.g. to further voltage levels of HV GIS.