Puget Sound Energy, Inc. 135 FERC ¶ 61,254 

In this order, the Commission accepts the SIL values identified in Appendix A (Commission-accepted SIL values). The Commission-accepted SIL values identified in Appendix A will be used by the Commission to analyze updated market power analyses submitted for the Northwest region. SIL studies are used as a basis for calculating import capability to serve balancing authority area load when performing market power analyses.

SIL values quantify a study area’s simultaneous import capability from its aggregated first-tier area. The SIL values accepted herein, with one exception noted below, were submitted by the Northwest Transmission Owners with their updated market power analyses. The SIL values we accept include SIL values provided by some of the Northwest Transmission Owners for first-tier balancing authority areas that are not operated by public utilities as defined under Part II of the Federal Power Act (FPA).

Additionally in this order, based on its experience in reviewing SIL data provided over the past three years from sellers in all regions of the country, the Commission provides further direction and clarification on the performance and reporting of SIL studies. Going forward, when filing updated market power analyses with the Commission, filers are directed to submit their SIL data in the format provided in Appendix B of this order in order to properly summarize and document their SIL study results. Transmission owners should also use the Appendix B format when sharing SIL results with one another. Also in Appendix B, we provide a detailed itemization of the reporting requirements for SIL studies to facilitate their filing and review.

This page was last updated on December 04, 2023