115 KV Substation: 50 MW Load Interconnection & Infrastructure Optimization

High-Impact Load Integration: Integrating a new 50 MW load into Avangrid’s 115 kV transmission system required precise substation modifications to uphold reliability and meet growing demand.
Legacy Asset Repurposing: Relocating the Cayuga GSU transformer feeder posed technical and spatial challenges within existing infrastructure constraints.
Operational Segmentation: Maintaining functional independence between customer and utility necessitated meticulous meticulous separation in alignment with utility ownership protocols.
Strict Regulatory Compliance: The project demanded adherence to a complex matrix of standards—NERC, NPCC, NYSRC, NYISO, and NYSEG—through rigorous studies and infrastructure validations.

Detailed System Studies: DST performed detailed thermal, voltage, stability, and load flow assessments of the Milliken substation and Cayuga’s 115 kV systems.
Substation Infrastructure Upgrades: Identified and designed high-side equipment modifications to accommodate the repurposed GSU transformer and ensure compatibility with the load’s dynamic profile.
Protection & SCADA Enhancements: Evaluated existing protection schemes and developed relay, SCADA, and communications upgrade plans in coordination with NYSEG and Avangrid standards.
Metering Reconfiguration: Proposed metering system redesigns for compliance, accuracy, and seamless integration with utility-owned metering architecture.
Asset Demarcation Strategy: Designed and documented a separation plan for shared facilities, ensuring clear operational boundaries and eliminating system interdependencies.

Structured Deliverable Rollout: Delivered a phased engineering package culminating in a PE-stamped Final Facility Study Report with detailed technical, financial, and compliance insights.
Compliance-Centric Engineering: Delivered a technically robust and regulation-ready solution, ensuring full alignment with regional grid codes and interconnection mandates.
Tailored Technical Execution: Customized engineering based on substation-specific constraints and the 50 MW load’s operational flexibility, including DSM compatibility.
Cost-Effective Infrastructure Utilization: Optimized existing assets for reuse, minimizing capital costs while enhancing system resilience and performance.

DST provided data, maps, charts, and calculations in a format easily accessible by ComEd.
DST successfully identified necessary grid upgrades and provided cost estimates for DER integration.
Throughout this program, DST ensured smooth communication and documentation, meeting regulatory and technical requirements for DER interconnection.

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