The NERC Interchange Distribution Calculator (IDC) is an integrated, versatile system that has evolved over a 10-year period to meet a variety of congestion management needs. It’s gone from a tool to assist Reliability Coordinators in the implementation of TLR procedures through the curtailment of interchange transactions, to managing interconnection-wide congestion through the implementation of NAESB Business Practices and NERC Reliability Standards, to providing seams coordination between markets and between market and non-market entities through transaction curtailment and market and Balance Authority re-dispatch obligations.
Every 20 minutes, the IDC computes distribution factor matrices relating 7,000 generators and 400 aggregated injection points to 1,600 flowgates. It takes into account planned and forced transmission and generator outages that impact the flow distribution across the network grid.
The OATI state-of-the-art webSAS solution is fully compliant with WECC Unscheduled Flow Mitigation Procedure (USF). It provides power marketers and Balancing Authorities with an automated Unscheduled Flow Assessment Tool to meet the WECC’s USF reduction requirements by initiating adjustments to meet the relief obligations. It also provides a way for users to enter any alternative actions they may have taken to remain compliant.