1. Historical Analysis WG Report to TEPPC June 12, 2008

2. Overview 1.Historical Path Flow Database 2.Historical Schedule and ATC Database

3. I. Historical Path Flow Data Now have database of hourly path flows for 34 WECC paths - 2006-07 Completed flow distribution plots for all 34 paths (see sample plot) Path Plots are posted on the WECC web site on HWG page

5. Next Step – For all major paths, calculate and plot: –Chronological yearly plots –Seasonal and Heavy/Light load hour flow distributions –Congestion Indices (U75 & U90) – seasonal and Heavy/Light load hour See example Plots for Path 8 (for MT to NW)

8. II. Historical Schedule and ATC Data OATI proposal – Gather Schedule & ATC data –Change Order to the Western Interchange Tool (WIT) –Historical hourly data, 2006-07, 30 paths, both path directions –Data sources: Schedules – Etags, ATC – WestTrans OASIS –Aggregate data from POR PODs to WECC paths –WECC responsibility - - map POR PODs to WECC paths –Provide data to WECC in 90 days (about Oct 1, 2008) –OATI will work with each TP re. schedule and ATC methodology Plan to tell OATI to proceed after we finalize a contract with DOE/LBNL for a WECC historical study

9. US DOE/LBNL contract – DOE/LBNL provides funding to WECC to perform a western historical congestion study for use in DOE’s 2009 Congestion Study –WECC gathers historical flow, schedule and ATC data –WECC analyzes historical flow, schedule and ATC data –WECC calculates congestion indices –WECC identifies historical path usage and congestion areas –WECC submits report to US DOE by December 31, 2008 –Contract should be finalized in 1 to 2 weeks

10. QUESTIONS