USA, Rhode Island, Providence: National Grid tackles the challenges of replacing a 100-year-old substation in the heart of Providence.
The South Street substation was originally opened in 1919 as a part of critical infrastructure to help keep the lights on in Providence. It was a 115 / 11.5 kV station consisting of three 115 / 11.5 kV power transformers, four 11.5 / 23 kV transformers, an interconnecting bus, and 11.5 kV, three-section, segregated phase switchgear.
At 100 years old, equipment at the substation was no longer supported by the manufacturer. In 2016, the utility broke ground on the new substation, including a completely new building to house the infrastructure along with outdoor switching equipment.
When designing the substation, National Grid sought to install state-of-the-art technology.
National Grid installed 63 kA rated arc-resistant switchgear manufactured by Siemens to replace the dated breakers and protection scheme in the old substation.
Fiber-optic cables were installed as a communication means between the new South Street substation and connecting substations.
Because of the limited space available to build a new substation while keeping the existing substation operational, TRC Companies Inc. was contracted to design a building to house some of the major equipment, including the 63 kA switchgear, indoor reactors and switches. The basement of the control building houses more than 25 11.5 kV distribution circuits, which required a complicated layout. TRC adopted the Bentley substation tool to create 3 D models and walk-throughs to present, discuss and fine-tune South Street’s complicated design.
The final cost of the station was $85 M.
The new substation was finally completed, energised and brought on-line in the spring of 2019. Demolition of the old substation was the last task to be done. It completed in the fall, with the last brick of the old station being hauled away in November 2019.
This new super substation is enabling National Grid to contribute to the revitalization of downtown Providence and transform the land near I-195.
The new substation also is significantly easier to operate and maintain.
From the complexity of the substation and the congested work zone to the challenges of demolishing the old substation and working with the many partners involved with the development of the downtown area, the vast scope of work made the South Street substation a challenging yet rewarding project.
With this new super substation in place, Providence will be powered well into the future.
Source: T&D World