Squaw Creek Substation Upgrade Project
Specialty Engineering, Inc. (SEI) has been providing Salmon River Electric Coop (SREC – Challis, ID) maintenance and testing services for all of its substations. During the 2020 annual maintenance cycle SEI helped SREC identify many needed capital improvement projects, one of which included the Squaw Creek Substation. With ever increasing loads, minimal protection scheme, and limited ability to control the Squaw Creek substation this project was identified as being one of the higher priority projects to execute. From 2022 to 2024 SEI, working with its sister company EPS (Olympia, WA office), provided a completed design/build upgrade of the Squaw Creek Substation.
Services included design and construction tasks as follows:
- Replacement of the existing 69 kV primary fuse protection with a new SF6 3 phase 69 kV gas circuit breaker (GCB). Included precast foundation design (to minimize outage cutover time), GCB specification documents, GCB procurement assistance with SREC, coordination of the precast foundation procurement and delivery, and final installation/testing/commissioning of the new GCB.
- Replacement of the existing three single phase transformers with a new upsized 3 phase transformer. Included bid and specification document preparations for the new transformer, close coordination of the footprint of the new transformer to rest on the existing pad (to minimize outage cutover time), bid selection assistance, Factory Acceptance Testing (FAT) of the select transformer, transmission and distribution buss reconfigurations, spill containment construction, and final installation/testing/commissioning of the new transformer.
- Upgraded relay protection to include new differential and overcurrent coordinated protection. Included new underground conduit and control cable installations between the new GCB and transformer pads to the control house. This work also included relay settings development, implementation, and retro-fitting new relays into the existing control house panel.
All of the work was completed on time and under budget.