1. August 27, 2015 Technical Advisory Committee (TAC) Update to RMS Kathy Scott September 1, 2015 TAC Update to RMS1

2. ERCOT Board Update August 11, 2015 Board Meeting: ◦ All Revision Requests submitted by TAC to the ERCOT Board was approved through a consent vote. ◦ Meeting was Uneventful! September 1, 2015TAC Update to RMS 2

3. PRS Initiatives and Votes Nodal Protocol Revision Requests (NPRRs) ◦ NPRR704, Revisions to the Size of Aggregate Generation Resources- Unanimously Approved by TAC Discussion of Implementation of Revision Requests via ERCOT Manual Processes: ◦ Concerns voiced was cost of implementing automated processes for projects that were expected to be short-term or stop gap solutions. ◦ ERCOT seemed to be advocating for more automated processes that increases overall project costs, ERCOT’s response was they are trying to mitigate risk to the market and ERCOT’s reputation. ◦ Action Item for PRS: Conduct additional discussions and come back to TAC with recommendations, per TAC Leadership Consider how the market should mitigate risk? September 1, 2015TAC Update to RMS 3

4. Tabled and/or Withdrawn Revisions Request Previously Tabled at TAC (Possible Vote): ◦ RMGRR129, Revision to Customer Rescission Completion Timeline  8/27/15: TAC Unanimously Approved with an implementation date of October 1, 2015 that was unanimously approved by RMS and recommended by the MarkeTrak Taskforce. ◦ VCMRR007, Alignment with NPRR699, Energy Offer Curve Caps for Make-Whole Calculations for Resource Type Other  8/27/15: TAC Unanimously Approved ◦ VCMRR008, Alignment with NPRR700, Utilizing Actual Fuel Cost in Startup Offer Caps  8/27/15: TAC Unanimously Approved September 1, 2015TAC Update to RMS 4

5. Reliability Operations Subcommittee (ROS) ◦ RRGRR006, Clarification of Descriptions and Alignment with Resource Asset Registration Forms (Vote)  8/27/15: TAC Unanimously Approved.  RRGRR006 will need to go before the Board for final approval because of it includes cost impacts to implement. Wholesale Market Subcommittee (WMS) ◦ SAWG Update on Real-Time Co-optimization ◦ WMS, and maybe ROS, will need to do a deeper dive into this project and on the cost issues can ERCOT refine their cost estimates?  Can changes that have already occurred in the market impact the estimates that ERCOT has previously completed? ◦ Cost Estimates will need to be performed by both Market Participants and ERCOT that will be discussed at TAC in a couple of months. September 1, 2015TAC Update to RMS 5 ROS and WMS Initiatives and Votes:

6. Retail Market Subcommittee (WMS) ◦ RMGRR131, Guidelines for Notification of Invoice Dispute (Vote)  8/27/15: TAC Unanimously Approved  NOTE: These changes were implemented and effective on Tuesday, September 1, 2015 Commercial Operations Subcommittee ◦ LPGRR055, Extend Load Profile Model Calendar Inputs to 2030 (Vote)  8/27/15: Unanimously Approved “Tabling” for another month to allow the implementation date to be October 1, 2015 as recommended by COPS and PWG  September 1, 2015TAC Update to RMS 6 RMS/COPS Initiatives and Votes

7. DREAM Taskforce Update DREAM Taskforce Update Distributed Resource Energy and Ancillaries Market Taskforce (DREAM) ◦ DREAM Taskforce Update:  DREAM meeting planned each month will focus on:  September: Definitions, Reporting, Distribution Awareness, and DR Aggregation Rules  October: Interconnection Procedures, Metering, and Modeling  November: Local Pricing (Nodal), Resource Optionality  December: Compliance Metrics, Review of TAC-level Policy Cuts  January: TAC Presentation: Policy Cuts  http://www.ercot.com/content/wcm/key_documents_lists/72879/10. _DER_Whitepaper_082015.docx http://www.ercot.com/content/wcm/key_documents_lists/72879/10. _DER_Whitepaper_082015.docx September 1, 2015TAC Update to RMS 7

8. Ancillary Services Re-design Update Ancillary Services Re-design Update FAS (NPRR 667)  2024 Ancillary Services requirements planning documents will be posted in a couple of weeks.  Plans are to complete by Friday, September 4 th –  Cancelled August FAS meeting and rescheduled for September 21, 2015.  http://www.ercot.com/calendar/2015/9/21/73816-FAST http://www.ercot.com/calendar/2015/9/21/73816-FAST  Planning to have Brattle report by end of October 2015  November 9 th FAS CBA presentation  http://www.ercot.com/calendar/2015/11/9/73769-FAST http://www.ercot.com/calendar/2015/11/9/73769-FAST  Preparing comments for NPRR667 September 1, 2015TAC Update to RMS 8

9. Operations, Planning and IT Report Reserves Analysis of Reserves and Prices ◦ Why so High or Why so Low?  http://www.ercot.com/content/wcm/key_documents_lists/72879/12._07272 015_08232015_Analysis_of_Reserves_and_Prices_TAC.pptx http://www.ercot.com/content/wcm/key_documents_lists/72879/12._07272 015_08232015_Analysis_of_Reserves_and_Prices_TAC.pptx Monthly Responsive Reserve (RRS) requirements in July and August 2015  Per ERCOT the reason for variances are due to errors created by manual processes and manual inputs.  ERCOT would like to come to the market with an SCR to automate these processes to remove this risk.  Action Item: ERCOT will provide TAC with reports and analysis provided to the Board EC meetings. September 1, 2015TAC Update to RMS 9

10. Operations, Planning and IT Report Impacts of EMS Coding Issue and Update on Communication’s Plan:  Three Options:  Discover the coding issue that ERCOT knew was a bug, ERCOT fixed it and used the next 10 days to explore impacts to the market to be prepared for questions from the Market. 1.Fix the bug immediately and communicate – may not know root cause, market impacts and long term affects until later 2.Fix the bug immediately, communicate once information is available. 3.Find the bug, but don’t fix until communicated with the market.  Additional Suggestion: Use the Retail Market Subcommittee’s Notification model and establish a Market Call.  TAC membership agreed that Option 1 – Fix the bug immediately and communicate to market- ERCOT may not know root cause, market impacts and long term affects until later—Use RMS Notification model and establish a Market Call to allow for Q&A. September 1, 2015TAC Update to RMS 10

11. Other Business Revisions to TAC Procedures (Vote) ◦ Unanimously Approved as submitted to TAC. Board will need to confirm these changes during their October meeting. Draft 2016 Block Committee Calendar September 1, 2015TAC Update to RMS 11

12. 2015 TAC Structural Review & Goals TAC Subcommittee Structural and Procedural Review and TAC Goals Review ◦ Alignment of TAC Goals and Approved Revision Requests with TAC Goals and ERCOT Strategic Plan  http://www.ercot.com/content/wcm/key_documents_lists/72881/02._2015_ TAC_Goals.doc http://www.ercot.com/content/wcm/key_documents_lists/72881/02._2015_ TAC_Goals.doc  http://www.ercot.com/content/wcm/key_documents_lists/72881/02.__Revi sion_Request_Alignment_with_2015_TAC_Goals_081815.xls http://www.ercot.com/content/wcm/key_documents_lists/72881/02.__Revi sion_Request_Alignment_with_2015_TAC_Goals_081815.xls ◦ TAC Subcommittee Structural Review  Committee Strategic Alignment  Frequency/Efficiency of Meetings  Working Groups/Taskforces  http://www.ercot.com/content/wcm/key_documents_lists/72881/03._2015_ List_of_Subcommittees_WGs_TFs.v2.xls http://www.ercot.com/content/wcm/key_documents_lists/72881/03._2015_ List_of_Subcommittees_WGs_TFs.v2.xls ◦ Review of ERCOT Membership Categories September 1, 2015TAC Update to RMS 12

13. 2015 TAC Structural Review & Goals Key Discussions and Highlights: ◦ At the October Board the TAC Leadership will provide updates on the status of the TAC goals that align with approved revision requests. ◦ Stressed: Working Groups and Taskforces need to get their agendas out along with any key documents posted to the ERCOT calendar 7 Days prior to meeting. ◦ Reviewed each Subcommittees list of Working Groups and Taskforces– for the most part the major concerns were not with COPS and/or RMS’ Working Groups and Taskforces. ◦ Discussed Meeting schedules and if there are meetings that can be combined with other meetings, held by web conference or cancelled to allow for the best use of $$$ and attendance. September 1, 2015TAC Update to RMS 13

14. 2015 TAC Structural Review & Goals Key Discussions and Highlights: ◦ Discussed if TAC meetings should meet on a by- monthly schedule opposite the Board Meetings or go to quarterly:  Majority of attendees didn’t support quarterly, but could support by-monthly meetings opposite the Board meetings to take care of voting items and to prepare for the Board updates.  Suggestion – Informational/update meetings could be held in between face to face meetings to address any Adhoc issues or significant market impacts. Also, could call emergency meeting(s) on an Adhoc basis.  Consensus: Keep a placeholder each month on the ERCOT calendar and plan to have face to face meetings by-monthly opposite the ERCOT Board meetings. ◦. . September 1, 2015TAC Update to RMS 14

15. 2015 TAC Structural Review & Goals Key Discussions and Highlights: ◦ Review of ERCOT Membership Categories:  What are the different categories for membership?  Who can become a member?  Could Distributed Generation Providers be the equivalent of an Independent Generator?  ERCOT legal will look at this to determine what changes are needed if any and discuss at TAC at a later meeting. ◦ Structural Review Discussions/Recommendations will be brought forward to the September TAC meeting! September 1, 2015TAC Update to RMS 15

16. Questions? 16 September 1, 2015TAC update to RMS