1. Interchange Scheduling & Accounting Subcommittee (ISAS) Charles (Bud) Freeman, SCL W ESTERN E LECTRICITY C OORDINATING C OUNCIL

2. ISAS Activities Leadership Change – Raymond Vojdani (Vice Chair) EIM Education Preschedule Calendar (2017vote April Mtg.) ATF Guidelines Spring Schedulers Meeting WIT Functionality Survey 2 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

3. Highlights Interchange Work Group (IWG) – Review preschedule calendar guidelines – INT-21 WIT Checkout Confirmation – WIT Interchange Authority Back-Up asking for volunteers to participate in the WIT Interchange Authority Back-Up which is a tabletop exercise of regional criteria INT-20. 3 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

4. Highlights Electronic Scheduling Work Group (ESWG) – Conducted a survey among the WECC BAs – ESWG goal was to determine what works and what doesn’t work with WIT – 33 out of 38 BAs responded to the survey – A wide range of usage was reported by the BAs – Majority of the BAs use WIT for their BA Checkout, Inadvertent Accounting, and Primary Inadvertent Interchange (engine) calculation – Several BAs use WIT calculated NSI to drive their AGC 4 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

5. Highlights Overall, the survey didn’t indicate major shortcomings with WIT Few deficiencies or need for enhancements were reported The ESWG shared the survey results to Peak RC staff The ESWG will follow up with Peak RC staff to assure the issues are adequately addressed For more information, please see ESWG’s Jan. 2016 Report to ISAS 5 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

6. Spring Schedulers Meeting Focus on quantifiable education – Planning 6 hours of NERC Continuing Education – EIM table top exercise – Outreach and training on ATF tagging – Scheduled for May 24-25, 2016 in SLC 6 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

7. ATF Guidelines ATFWG Chair Sheryl Welch, Bonneville Power Administration Developing ATF Tagging Guidelines No consensus among membership Follow up report from October OC ISAS working to review and possibly update the Guidelines as needed 7 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

8. ATF Tagging Report – Follow Up Andy Meyers reported on ATF tagging during October 2015 OC Meeting Follow up – Why has there be an increase in ATF tags? – What are the main reasons for ATF tags? – Provide more detailed data on ATF Tags 8 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

9. ATF Tags Accounting Accounted for Differently Over the Years Prior to 2014 Reported by Tag Post 2013 Reported by ATF Hour Normalized trend is Relatively Flat. Unusual Event in 2014 skewed count Getting more tag details would require a change order with OATI. The WIT contract is with PeakRC. 9 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

10. Normalized ATF Tag Data REASON2016 2015201420132012 Incorrect Path or Sched Entity266568272 Scheduling or Adjusting Error 21201636 System Error 031227 Generation/Meter Adjustment 50402631 Incorrect Source / Sink 132031116 Curtailment Error 03312 Incorrect PSE 0085 RSG Tag Error289189 Integration Error 1024 Tag Type Correction 04900 Incorrect Tag 6802118 WIT not match OAIT Tag 8000 Oversold 1000 Unknown 0401 No Original Tag1 TOTAL5236383199231 Originally Reported8887 Current MW 35584022662167912896 Changed to MW 262301961413657691 Total MW Change 93539130483145205

11. ISAS ATF Effort There has been significant discussion in ISAS to define when ATF Tags are appropriate Diverging views both regionally and between TP’s vs PSEs ISAS leadership will provide additional outreach and education to the WECC members (Agenda Item for Upcoming Scheduler’s Meeting in May) 11 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

12. ATF Tagging Guidelines Reasons to Create ATF Tags ATF tags are used by Balancing Authorities (BAs or CAs), Transmission Service Providers (TSPs), and Scheduling Entities (SEs) to accurately reflect a schedule which was coordinated and controlled by a BA’s Energy Management System (EMS) and Automatic Generation Control (AGC) system during real time system operations, but was not properly tagged. Missing or incorrectly used CA (Balancing Authority), TP (Transmission Provider), or SE (Scheduling Entity) Missing adjacencies or incorrect Point of Receipt or Point of Delivery segment(s) When there is an Emergency and WIT system goes down. ATF tags shall not be used for market driven manipulations. NOTE: When an ATF tag is needed to correct a dynamic tag, the tag type is normal. 12 W ESTERN E LECTRICITY C OORDINATING C OUNCIL

13. Questions? 13 W ESTERN E LECTRICITY C OORDINATING C OUNCIL