A number of options for reducing the footprint of substations using conventional Air-Insulated Switchgear (AIS) have been identified. A compact AIS design would have advantages in applications where restrictions in the available land are encountered. For example, such a design might allow extension bays to be constructed within an existing substation boundary where space is restricted.
Potential applications also arise where a replacement substation is to be constructed off-line on land adjacent to an existing substation, allowing the latter to remain in service during the construction period and avoiding the safety and operational issues associated with bay-by-bay replacement. Applications might also be found in urban areas. In such cases, a compact AIS substation might offer a cost-effective alternative to Gas-Insulated Switchgear (GIS) substation and would reduce dependence on Sulphur Hexafluoride (SF6), the use of which is being questioned on environmental grounds. The identified options for reducing the footprint of AIS substations are being investigated in the present work.