This NPRR adds a new definition of Outage Planning Contingencies to be consistent with NOGRR078 and PGRR011. This NPRR also revises factors used by ERCOT to evaluate requests for Generation and Transmission Outages received from Market Participants to allow for 90th percentile variation of weather driven Load, generation availability, and transmission line ratings of dynamically rated lines. This NPRR ensures that Outage planning studies do not double count generation capacity as being available simultaneously for both congestion management and Ancillary Services including Responsive Reserve (RRS), Regulation Up (Reg-Up), and Non-Spinning Reserve (Non-Spin), unless ERCOT Operations has processes in place to allow for location specific deployment of the Ancillary Service reserves for congestion management purposes. Finally, this NPRR ensures that, if in Real-Time operations ERCOT determines that a generic constraint definition and associated transfer limit(s) is required for secure operation of the ERCOT System, then this same generic constraint shall be similarly modeled in Outage planning studies.
The ERCOT Technical Advisory Committee (TAC) directed the Planning Working Group (PLWG) of the Reliability and Operating Subcommittee (ROS) to develop planning processes that eliminate the gap between operations and planning in order to significantly reduce the amount of unmanageable constraints that have been observed in Real-Time operations. It is recognized that unmanageable constraints in Real-Time can arise for a variety of reasons, only some of which may be improved with these outage planning recommendations; while many of the others may be improved with transmission planning enhancements. The language changes contained in this NPRR represent the modifications to the transmission planning process discussed by the Joint PLWG/Congestion Management Working Group (CMWG) and apply them in a complementary fashion to the Outage planning process that aligns with PGRR011.