Confidential Client
Midwest USA
Power & Energy
Overview
A major investor‑owned electric utility serving millions of customers across the Midwest and Mid‑Atlantic regions undertook a critical infrastructure upgrade at its major substation location in the Midwest. The client owns and operates an extensive electric transmission and distribution network that underpins regional economic activity, industrial operations, healthcare systems, and community services. Maintaining grid reliability, operational flexibility, and long‑term system resilience is central to the client’s mission as energy demand continues to grow and electrical infrastructure ages.
To support these objectives, the client initiated a comprehensive expansion of the existing 138 kV electrical substation. The primary goal of the project was to significantly enhance system reliability and operational flexibility by converting an existing four‑breaker ring bus into a six‑breaker configuration, while maintaining continuity of service and adhering to evolving grid standards. This effort relied on disciplined substation engineering and robust electrical substation design practices to ensure constructability and safety.
The project scope included detailed engineering for the installation of two new 138 kV breakers, replacement of existing breakers and disconnects, looping two major transmission lines in and out of the substation, and the addition of a new control house to support expanded protection, control, and SCADA functionality. The expansion required extensive electrical, structural upgrade planning, and coordination efforts to integrate new infrastructure into an active, in‑service electrical substation environment, strengthening the client’s transmission and distribution capabilities.
Challenge
This Midwest substation project presented several technical and execution challenges that required a high level of coordination and engineering rigor in substation engineering and civil/structural disciplines.
One of the most significant challenges was the scale and complexity of the expansion within an existing, operational substation. The conversion to a six‑breaker ring bus required the replacement and addition of critical high‑voltage equipment while maintaining system reliability and complying with bulk electric system requirements. The project involved replacing existing breakers and disconnect switches, installing additional breakers and group‑operated disconnects, adding multiple CCVTs and surge arresters, and modifying all line exits with motor‑operated air‑break switches. Ensuring grid reliability during cutovers demanded meticulous electrical substation design.
Long‑lead equipment and evolving standards further complicated execution. Major components such as 138 kV breakers, control house equipment, and structural steel carried extended procurement timelines—some exceeding 100 weeks. At the same time, owner standards and industry requirements continued to evolve throughout the design phase, requiring the engineering team to remain flexible and responsive while preserving schedule integrity and safeguarding critical electrical infrastructure.
The project also required significant civil and structural upgrades, including the installation of approximately 100 new foundations, extensive replacement of existing bus work and steel structures, and coordination of more than 450 electrical circuits involving thousands of individual connections. Site constraints and layout limitations demanded careful planning to avoid encroachment issues, maintain required clearances, and ensure constructability. Each structural upgrade was closely coordinated with the energized yard to maintain safe operations within the electrical substation.
Finally, multi‑discipline coordination was critical. Electrical, protection and controls, structural, project services, and project management teams had to remain tightly aligned across a multi‑year design effort, with frequent reviews, owner coordination meetings, and quality control checkpoints to ensure consistent progress and risk mitigation across the broader transmission and distribution system.
Solution
The project team delivered success through disciplined project management, proactive coordination, and deep substation engineering expertise focused on resilient electrical infrastructure.
From the outset, the team established a structured execution framework that emphasized early identification of long‑lead equipment, continuous alignment with owner requirements, and frequent internal and external coordination. Regular bi‑weekly meetings with the client, combined with weekly internal discipline reviews, allowed the team to quickly address evolving standards, resolve technical issues, and manage action items before they impacted schedule or quality, thereby supporting grid reliability.
To manage the complexity of the expansion, the team developed highly integrated electrical and structural design packages, ensuring that new breakers, disconnects, bus work, foundations, and control systems were seamlessly incorporated into the existing substation. Detailed constructability reviews and standardized electrical substation design approaches helped reduce risk and improve clarity for downstream construction activities and structural upgrade execution.
The addition of a new control house was a key differentiator for the project. The team engineered a modern facility housing seven relay frames, a human‑machine interface (HMI), a remote terminal unit (RTU), and new AC and DC auxiliary systems. Extensive coordination ensured reliable integration between new protection and control systems and the existing substation infrastructure, reinforcing the client’s electrical infrastructure and enhancing operational visibility across the transmission and distribution network.
Through disciplined planning, schedule management, and technical execution, the team delivered a comprehensive engineering solution that strengthens grid reliability, enhances operational flexibility, and positions the substation for long‑term service in a rapidly evolving energy landscape through best‑practice electrical substation design and substation engineering.
Services Provided
- Substation detailed engineering (138 kV systems) aligned to resilient electrical substation practices
- Ring bus expansion and equipment replacement design to support grid reliability
- Protection & control schematics and wiring design for critical electrical infrastructure
- Physical layout, grounding, and conduit design within active electrical substation yards
- Structural and foundation engineering for each structural upgrade
- Control house design, AC/DC systems, and SCADA integration across the transmission and distribution footprint
- Long‑lead equipment identification and procurement support
- Multi‑discipline coordination and quality assurance for complex substation engineering
- Project scheduling, reporting, and owner coordination
- IFC and as‑built documentation support
Project Director
