Gas Insulated Substation: Learn the Purpose, Cost, and Lead Time to Procure

Gas insulated substation
GIS substation

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.


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Gas Insulated Substation: Learn the Purpose, Cost, and Lead Time to Procure 1

Substation Major Equipment

It’s only stupid-simple, let’s begin.

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