Mitsubishi Electric - Gas Insulated Switchgear (GIS) - Brochure

Mitsubishi Electric began its industry leadership in Gas Insulated Switchgear (GIS), building its first in 1968. In 1973, it installed the first 500kV hybrid gas-insulated substation. Three years later, Mitsubishi Electric constructed the world’s first 550kV fully gas insulated switchyard at the Ohi Nuclear Power Station, which is the largest nuclear power plant in Japan. Since then, more than 20,000 GIS bays have been installed in substations worldwide.