Lead from the front Texas Nodal 1 EDS 4 DAM/RUC/SASM EDS 4.9 Market Call April 4, 2008

Lead from the front Texas Nodal 2 ERCOT Anti-Trust Admonition ERCOT strictly prohibits Market Participants and their employees who are participating in ERCOT activities from using their participation in ERCOT activities as a forum for engaging in practices or communications that violate the antitrust laws. The ERCOT Board has approved guidelines for members of ERCOT Committees, Subcommittees and Working Groups to be reviewed and followed by each Market Participant attending ERCOT meetings. If you have not received a copy of these Guidelines, copies are available at the Client Relations desk. Please remember your ongoing obligation to comply with all applicable laws, including the antitrust laws.

Lead from the front Texas Nodal 3 Agenda DAM/RUC EDS 4 –Current issues –Release 9.3 update –Release 8 Update –Q&A and Roll Call Appendix

Lead from the front Texas Nodal 4 Current issues – EDS environment Querying submissions sent via API on the Market Manager –Must update the Bid ID field on the query page: If you submit via API, you must enter this to match the Bid ID of your submission Updating submissions sent via API on the Market Manager –Must use Bid ID of when submitting the transaction via API When attempting to update submission, a new transaction is created instead Temporary workaround until fix in for Market Manager Intermittent issues with credit limit calculation –Some QSEs had issues with credit limit errors when submitting from of the DAM Intermittent issue- so please let us know if you had this problem and send the error Several issues are the result of some individual data issues with ERCOT All self-arranged AS transactions will be rejected from –we are working on a fix for Tuesday submission

Lead from the front Texas Nodal 5 Updates – Documentation A new version of the Market Manager User Guide is available –New Awards tab next to Notices [will appear soon] –Currently display GetAwardSet only; a download option available in mid-April –Download from Readiness Center Changes to GetAwardSet (draft XSD’s being posted) –As communicated last week, there were issues with payload size of GetAwardSet. –Resolving in two ways GetAwardSet query is being streamlined (EIP Spec v1.12) Creating ability to query awards by type –Draft xsd’s being posted and will be reflected in EIP Spec v1.12

Lead from the front Texas Nodal 6 DAM Execution Status ERCOT build-out and migration to integrated EDS4 DAM (MMS3) environment not yet fully complete –Approach is to migrate/update from Taylor to Austin in integrated fashion –Submissions this week were supported on MMS2 platform in Taylor Move to Austin site supports next level of integration –MMS, MIS, Current Day Reports, Market Manager, API-submission Submissions were re-played from Taylor/MMS2 platform to Austin/MMS3 platform yesterday afternoon –Some QSE received notifications from those migrated submissions –DAM execution still being worked, but parallel focus on completion of integration in Austin Market Manager functionality to view Awards is in Austin, so when DAM successfully executes in Austin, the Market Manager awards will be made available in Market Manager

Lead from the front Texas Nodal 7 Update on next phase- EDS4 Initial DAM/RUC Testing Next week we will continue DAM submissions for Initial DAM Execution –No changes to the supporting data Use the same Load Forecast and AS obligations as this week So for this Tuesday, re-submit the same data used this week with date of April 9 –Bidding Levels: 80% of Load for April 9 (DAM execution 4/8 for Operating/Trade Day 4/9) 120% of Load for April 11 (DAM execution 4/10 for Operating/Trade Day 4/11) –All QSEs are expected to participate (remember, sub-QSEs count)

Lead from the front Texas Nodal 8 Update on next phase- EDS4 Initial DAM/RUC Testing Will send update to DAM submission/timeline summary via distribution list and will post on Readiness Center

Lead from the front Texas Nodal 9 Update on next phase- EDS4 Initial DAM/RUC Testing Market Submission overview for April 4 –Energy Bids from QSEs with Load 10-20% of requested Load was not submitted

Lead from the front Texas Nodal 10 Update on next phase- EDS4 Initial DAM/RUC Testing Market Submission overview for April 4 (cont’d) –Self-Arranged AS from QSEs with Load 8-18% of requested Self Arrangement not submitted

Lead from the front Texas Nodal 11 Update on next phase- EDS4 Initial DAM/RUC Testing Market Submission overview for April 4 (cont’d) –Three Part Offers 94% of TPOs were submitted –Energy Only Offers 58 QSEs total submitted Energy Only Offers

Lead from the front Texas Nodal 12 Release 8 Update All “Standard” items posted to Readiness Center for review Standard outputs are defined as “a statement, invoice, or extract that is unassociated with any stubbed in data. “ See appendix slides for all Standard items posted for review Send acknowledgement of items to – this was due by 4/1/08 Please send these ASAP No Logged Issues No issues logged to date for Release 8

Lead from the front Texas Nodal 13 Release 8 - April Calendar of Events SAT/SUNMONDAYTUESDAYWEDNESDAYTHURSDAYFRIDAY 1-Apr2-Apr3-Apr4-Apr Download CRR Auction Invoices (Release 7.3) 5/6-Apr7-Apr8-Apr9-Apr10-Apr11-Apr 12/13-Apr14-Apr15-Apr16-Apr17-Apr18-Apr DAM Statements and Invoices Produced 19/20-Apr21-Apr22-Apr23-Apr24-Apr25-Apr Download CRR Auction Invoices (Release 7.4) DAM Statements and Invoices Produced 26/27-Apr28-Apr29-Apr31-Apr

Lead from the front Texas Nodal 14 Q&A / Open Forum Roll-Call

Lead from the front Texas Nodal Release 9.3 Information -Release 8 documents -DAM notifications available in Sandbox -Upcoming Network Changes -Connectivity information -Links to Key Documentation -Metrics -Data preparation APPENDICES

Lead from the front Texas Nodal 16 Update on next phase- EDS4 Initial DAM/RUC Testing Objectives beginning in April –QSE submit offers DAM/RUC –ERCOT executes DAM/RUC (in limited manner) –ERCOT posts awards and settlement point prices –Targeting to support out of Austin Control Center (ensure firewalls comply with Appendix) Schedule- –Run Day-Ahead markets on Tuesday and Thursday each week –Planned first DAM run is 10am on April 3 rd –ERCOT system and data preparation still in progress to make April 3 date Summary of how testing will evolve : –Execution functionality to be taken in steps (crawl > walk > run) Weeks 1&2 – –Energy-only DAM –No A/S, no RUC, no constraints, no PtP Obligations, no credit limit Week 3 – –Energy and A/S in DAM –Include self-selected credit limits and PtP Obligations Weeks 4 & 5 –Execute DAM with constraints on Tuesday, include RUC on Thursday

Lead from the front Texas Nodal 17 Update on next phase- EDS4 Initial DAM/RUC Testing (con’d) –Reminders below to involve business in building bids and offers ************************ –For testing purposes there will be guard-rails on data, but it will not scripted by ERCOT So QSE BUSINESS INVOLVEMENT IS CRITICAL for reasonable pricing and business activities –All QSEs (with and without Load and Resources)- May submit a limited amount of DAM Energy Only Offers and DAM Energy Bids that do not represent actual Resources or Loads (virtual bids and offers) QSEs can only bid/offer up to 50MW total (later becomes 500MW) Bids/Offers should net to 0MW total (later allowed to take position of up to 200MW) It is important that the submitted bids be reasonably priced for producing appropriate prices and results.

Lead from the front Texas Nodal 18 Release 8 - Documents available for review on Readiness Center Statements: Statement XMLs R2.xml XML R2.xml XML

Lead from the front Texas Nodal 19 Release 8 documents – page 2 Invoices: Invoices XMLs:

Lead from the front Texas Nodal 20 Release 8 documents – page 3 Multiple CRR Auction Invoices See section titled CRR Auction Invoices - Release 7.2 at the following location: Corresponding CRR Auction Invoice XMLs See section titled CRR Auction Invoices – Release 7.2 at the following location: Counterparty Available Credit Limit Report pdf pdf Total Potential Exposure Detail Report rty1_ pdf

Lead from the front Texas Nodal 21 DAM Awards Status of DAM Award Communication (as of 3/21/08) Due to integration issues, Notifications delivery moving toward mid-May Query Get AwardSet will conform to a temporary xml schema and will not conform to EIP specification in the beginning. We posted XSD on the Readiness Center. Note that this is an interim measure for first 2 weeks of April. –Awards queries will likely return compressed payloads given the size of the reports –GetAwardSet composed of: AwardedEnergyOffer AwardedEnergyOnlyOffer AwardedEnergyBid AwardedAS AwardedCRR AwardedPTPObligation Awards to be available via Market Manager (display of GetAwardSet)

Lead from the front Texas Nodal 22 DAM Awards DAM awards notification availability in the nodal Sandbox There is a scheduled job running in Sandbox that sends out notifications once a day (around 11:53 AM CST) To receive them, you must have your listener configured in the Sandbox environment – if you need it configured, send us an with your URL (send to NOTE: These notifications are generated from static files (pre-formed xmls) –AwardedCRR –AwardedAS –AwardedEnergyBid –AwardedEnergyOffer –AwardedEnergyOnlyOffer –AwardedPTPObligation –ConfirmedTrades –UnConfirmedTrades –OutageSet –ASObligations –StartupShutdownInstructions

Lead from the front Texas Nodal 23 Forthcoming Network Changes Network Changes / site to site fail-over testing (please communicate to your network / firewall teams) Test to be conducted mid / late March All QSEs need to have network changes in place no later than 3/14 The changes should enable receiving / sending data to / from:: » /24 » /24 » /24 Reminder: required ports do not change (443/80) Reminder: required protocols do not change (http/https)

Lead from the front Texas Nodal 24 APPENDIX- DAM/RUC Testing: Basic Communications Test (“Ping” Test) BASIC COMMUICATION TEST Prior to this test QSE’s using External Web Services will need to have their network and security teams make the following changes: –QSE’s Market System must be able to access: NOTE: this SSL URL is on port 80 NOTE: this is changed from Release –QSE’s must be able to receive messages from –QSE’s must be able to send messages to EDS Environment: Sandbox Environment: QSE’s using MIS User Interface will need to have their network and security teams make the following changes: –Must be able to access: MIS URL: NOTE: MMS User Interface will have link from MIS NOTE: MIS/MMS UI are on port 443https://nodaleds.ercot.com/misportal/

Lead from the front Texas Nodal 25 APPENDIX- DAM/RUC Reference: Relevant Documents EDS – DAM/RUC/SASM Test Package Settlement Point Listinghttp://nodal.ercot.com/readiness/eds4/documents/index.html QSE Short Name Listinghttp://nodal.ercot.com/readiness/eds4/documents/index.html Dashboard of Metrics and Schedule EDS Issue Submission Form sue_submission_form.xls EIP External Interface Specification s_specification_v1_11.zip Explanation of Market Submissions v0.25

Lead from the front Texas Nodal 26 APPENDIX- DAM/RUC Reference: Relevant Documents ERCOT Nodal Transition Plan Plan_ doc EDS 4 Approach v1.0http://nodal.ercot.com/readiness/eds4/documents/index.html EDS 4 - DAM/RUC/SASM Market Participant Handbook v1.0 Market Management System User Guide mms_ui_draft_user_manual_ doc

Lead from the front Texas Nodal 27 APPENDIX- DAM/RUC Tracking: Readiness Metrics READINESS METRICS: MP8 - QSE Ability to Submit Transactions Via MIS –Expected completion date March 15 MP9 – QSE Ability to Submit Web Service Transactions –Expected completion date March 15 Execution –MP’s that have met readiness metric M8 or M9 by 3/15/08 are GREEN –MP’s that have attempted readiness metric M8 or M9 by 3/15/08 are AMBER –MP’s that have not yet attempted readiness metric M8 or M9 by 3/15/08 are RED MP16 - MP EDS-4 Trials Participation (phase 2) ERCOT is calling all QSEs that have not signed up for EDS4

Lead from the front Texas Nodal 28 Appendix- DAM/RUC Reference: QSE Data Preparation Reminder to Download Settlement Points and QSE Short Name List (both files posted on Readiness- Both data sets are subject to change QSE Short Names used in transactions –Your QSE short name is needed as in XML Header –All QSE short names listed, but may change Can use ERCOT test QSE of “TSTQSE” to avoid populating and changing QSE list in your systems Settlement Point used as points of business in submission testing –Market Participants revisiting Resource Node SPs –Considering change from Low side to High side –Change would result in many SP name changes