69-kV Downtown Substation

69-kV Downtown Substation

Location: Knoxville, Tenn.

Client: Knoxville Utilities Board

Completion Date: June 2000

The redevelopment of Knoxville, Tennessee’s, downtown area involved the construction of a new convention center and the redevelopment of the World’s Fair Park.  The convention center was to be built on the site of an existing substation that feeds electric power to downtown Knoxville.  To make way for the convention center this 66-kV substation had to be relocated.

The construction of the new substation was the first step on the critical path of the convention center; therefore, it had a very aggressive schedule of 12 months maximum for design, procurement, and construction, including all landscaping.

Burns & McDonnell’s goal was to make the substation as inconspicuous as possible, while achieving consistency of design with the convention center buildings and the surrounding area. Due to the area’s high profile, the new substation and its source and distribution lines were to be virtually invisible.

Aesthetic appeal, safety, operations and maintenance were all key elements to the design of the new substation.

To achieve the aesthetic appeal necessary to blend the substation into its scenery, Burns & McDonnell’s design called for putting the structure 20 feet below grade to ensure it would not be seen by a passerby.  An attractive 10-12 foot retaining wall surrounds the entire facility.  The drive leading into the site is curved to obscure the substation from anyone beyond the walls and extensive landscaping surrounds the structure, which incorporates the regional flora as well as blends into the scheme of the convention center’s landscaping.

Burns & McDonnell chose to use high-voltage gas-insulated switchgear (GIS), which requires very little maintenance and offers high reliability as demonstrated by hundreds of installations around the world.  The use of medium voltage metal-clad vacuum switchgear breakers allows thousands of breaker operations before maintenance is required.

For safety reasons, Burns & McDonnell was able to minimize the number of exposed energized parts by using gas-insulated-switchgear (GIS) technology.