The Central Electricity Authority’s (CEA) technical panel on the use of green gas insulated substation (GIS) technology in the Indian grid has recommended a phased and cautious rollout of SF6-free alternatives in the transmission system.

The committee has noted that technologies such as fluoronitrile-based gas mixtures and clean air with vacuum interruption offer lower environmental impact than conventional GIS, but their maturity varies across voltage levels. While deployment at 132 kV is considered feasible, application at higher voltages would require further field validation, operational experience and standardisation. The committee has recommended pilot projects at lower voltage levels under Indian conditions, followed by gradual scale-up based on performance, and has also highlighted the need to strengthen domestic manufacturing, testing infrastructure, gas handling practices and skilled manpower to support wider adoption.