The upcoming 400/200kV Siot substation in Jammu & Kashmir will now employ gas insulated switchgear (GIS) technology instead of the previously planned air insulated switchgear (AIS), following approval from the National Committee on Transmission (NCT).

The decision was made to address significant topographical challenges at the site, including a 60 mtrs. terrain level difference and a deep valley, which would have led to high construction risks and costs with the AIS setup. Despite GIS technology typically being more expensive, its ability to reduce civil work and risks associated with the site makes it a more cost-effective alternative for this project.

The project, which also includes a 15-km LILO of the existing 400kV Amargarh-Samba line, aims to boost power transmission capacity in the region. The Siot substation project, approved in August 2021, faced delays due to land finalisation issues, with the final site confirmed in January 2023.