Purpose of Gas Insulated Substation
Air has a dielectric strength of 33kV/cm. SF6 gas, on the other hand, has a dielectric strength of ~83kV/cm. Naturally, when the live parts are immersed in a pressurized gas chamber they can be placed a lot closer. Every piece of equipment (except the transformer or any other coil product) that makes up a substation can be neatly packed in an enclosed gear that is filled with SF6.
Cost of gas insulated substation
- Single leg/bay of 138kV breaker and a half substation (not including protective relays – equipment only): ~$500,000.
- 345kV gas-insulated bus only: ~$2,600 dollars per feet.
Lead time to procure gas insulated substation
~1 year
Information on cost and lead time is for your general knowledge only. Contact vendor with your equipment specifications for actual figures.
