A major milestone in the development of environmentally friendly high-voltage power equipment has recently been achieved in China.
Hitachi Energy announced the successful commissioning of the world’s first 550 kV SF₆-free Gas-Insulated Switchgear (GIS) at the Yuxian 500 kV Substation in Wuhan, operated by State Grid Corporation of China.
The project represents the highest voltage level ever achieved by a GIS system that does not use sulfur hexafluoride (SF₆) as the primary insulating gas. The successful energization demonstrates the technical maturity of next-generation environmentally friendly GIS solutions and supports the global transition toward low-carbon power infrastructure.
SF₆ has long been used in GIS equipment because of its excellent insulation and arc-quenching properties. However, SF₆ is also one of the most potent greenhouse gases, with a global warming potential approximately 24,300 times greater than CO₂.
To address environmental concerns, power utilities and equipment manufacturers worldwide are accelerating the development of alternative insulation technologies, including:
- SF₆/N₂ mixed gas systems
- Dry air insulated switchgear
- Fluoronitrile-based eco-efficient gas mixtures
- Other environmentally friendly insulating gas technologies
The successful operation of a 550 kV SF₆-free GIS marks a significant step toward reducing greenhouse gas emissions from high-voltage transmission networks.
As environmentally friendly GIS technologies continue to expand, accurate gas monitoring becomes increasingly important.
Compared with traditional SF₆ equipment, alternative gas systems often require:
- Gas composition analysis
- Mixed gas ratio verification
- Trace oxygen monitoring
- Dew point and moisture measurement
- Leak detection
- Gas recovery and handling
Reliable testing equipment is essential to ensure long-term operational safety and insulation performance.
Shanghai Yushi Technology Development Co., Ltd. (KSTONE) provides a range of testing and gas handling solutions for SF₆ and environmentally friendly gas-insulated equipment, including:
- SF₆/N₂ gas ratio analyzers
- Environmentally friendly gas analyzers
- Dew point and moisture analyzers
- SF₆ leak detectors
- Gas recovery and purification systems
- Mixed gas filling and handling equipment
As the power industry continues its transition toward greener technologies, KSTONE remains committed to supporting utilities, GIS manufacturers and service providers with reliable gas measurement and maintenance solutions.