1. Craig Quist TSS Representative PacifiCorp Transmission Path Definition Variations Technical Studies Subcommittee January 2012

2. 2 Path Rating Catalog (first 7 pages): ¶6: Document Update Policy Changes to an accepted or existing path rating must follow the WECC Procedures for Regional Planning Project Review and Rating Transmission Facilities (WECC Procedures). Minor changes to a path rating (such as moving a metering location) should be submitted as part of the 60 day Expedited Process defined in Part 2B, Section 3.0 of the WECC Procedures (assuming no comments require reissuing a study report). Changes to a path with an other path rating do not need to follow the WECC Procedures; however, the path will retain the other status.

3. 3 Path Rating Catalog (first 7 pages): ¶6: Document Update Policy (cont.) Changes to an accepted or existing path rating that do not follow the WECC procedures will be reclassified to other status. Although updated entries to the WECC Path Rating Catalog may be submitted to the WECC staff at any time, the catalog will be published once annually. Each path rating narrative shall indicate the date it was added to the catalog….

4. 4 In 2004, PNM had just completed the path rating for a new transmission path. The metering for one of four lines within the path required the metering to be moved from line end to the other. TSS required that PNM perform additional studies and present the findings to the PRG. Ultimately, no impact was seen with technical findings or path ratings. Transmission Path Definition Variations

5. 5 With the significant analysis that has been performed over the past few years, it is evident that impacts to tie line definitions, relative to path ratings, may not be as black and white as once thought… For example,

6. 6 Transmission Path Definition Variations The PNM example has demonstrated that moving metering points may not have an impact on system performance. Imbedding a new generation resource onto a transmission path may or may not have impacts on system performance. = ~

7. 7 Adding a new transmission line that intersects a transmission path may or may not have impacts on system performance. However, adding significant new facilities to a transmission path could impact system performance. Transmission Path Definition Variations or

8. 8 The current procedures call for minor changes to a path rating [definition] (such as moving a metering location) should be submitted as part of the Expedited Process. Under ideal conditions, the Expedited path rating process will generally take a minimum of six months to complete. Recommendation: TSS should consider if, for minor changes to a path rating definition, should another process be adapted? –Sponsor Presentation to TSS –Defense of Recommendation to TSS –TSS Direction –Etc. Something for TSS to ponder…

9. 9 Questions ?