External Web Services Update

1. External Web Services Update Nodal Implementation Team Presentation June 22, 2009 http://nodal.ercot.com 1

2. Agenda • External Interface Specification • Overview • Version 1.19 Changes Review • Comments / Questions Received • EIS Market Information Services Update • Background • Interface Review • Q&A

3. Overview • EIS 1.19 was released for comment on 6/5/09 • Comments closed on 6/19/09 • Most feedback received were general questions • Still processing / responding to several comments received Friday afternoon 6/19/09 • Sandbox • Current Sandbox implementation is 1.18 • 1.19 is targeted for Sandbox release on 7/7/09

4. EIS 1.19 Changes Review by Section • 2.3.6 - New Section - Enforced Precision information. • Market Submission and outbound Notifications (alerts, awards, etc.) enforced at XSD level – inbound & outbound • MW & MWh values - Enforcement of tenths of MW • Prices: 2 decimal digits (cents) • 2.3.7  - New section - XML Special characters • Handling of reserved characters in XML payloads (i.e., in Outage Creation “comments” field – use of &, ‘, “ etc.) • 2.6  - Removal of the SLA numbers - referred to the ERCOT EDS SLA http://www.ercot.com/services/sla/

5. EIS 1.19 Changes Review by Section • 3.3.9 – DC Tie Schedule – NERCTag is now part of the Energy Schedule (MMS5 addition)

6. EIS 1.19 Changes Review by Section • 4.0 Market Info updates: • 4.3.8 Forecasted Load – • Removed start/end time – Returns last available forecasted load values for next 7 days. • 4.3.10 – MarketTotals – • Removed start/end time- added OperatingDate – • Returns market Total energy bought or Sold in DAM for the requested Operating Date • 4.3.11 – LMPs/SPPs – • Added Request/OperatingDate for DAM Market type • Limited start/end time for RTM Market Type • 4.3.12 – MCPCs • Use TradingDate instead of StartTime/EndTime.  • Simplified the MCPCs structure • 4.3.13 – Binding Constraints – • Added Request/OperatingDate for DAM & DRUC market type – limited to end time for HRUC • 4.3.16 –Dynamic Ratings • Limited to EndTime on input.  Returning 7 day data. • 4.3.19 – LoadRatioShares – • Limited to OperatingDate- returning full requested day information • 4.3.20 - CompetitiveConstraints • Limited to OperatingDate on input.  Returning full requested day information. • 4.3.24- AggregatedASOfferCurves • Limited to OperatingDate on input.  Returning full requested day information for DAM and all SASMs found.

7. EIS 1.19 Changes Review by Section • 4.0 Market Info updates: • 4.3.25 – ASServicePlan • Corrected the example • 4.3.27 – StartupShutdownInstructions – • Added report Date, Option addition for MarketType – replaced Start/EndTime with Trading Date • 4.3.28 – TotalASOffers • Limited to OperatingDate on input.  Returning full requested day information for DAM market. • 4.3.29 – TotalEnergys • Limited to OperatingDate on input.  Returning full requested day information for DAM market. • 4.3.31 – WeatherInfo • Limited to OperatingDate on input.  Returning full requested day information. • 4.3.39 - WGRPP • Limited to EndTime on input.  Returning hourly data for the requested hour. • 4.3.40 – STWPF • Limited to OperatingDate on input.  Returning full requested day information. • New 4.0 Market Info Interfaces: • 4.3.49 – New Interface: MarketInfo: EndAdjPeriod • 4.3.50 – New Interface: MarketInfo: TwoHrNotif • 4.3.51 – New Interface: MarketInfo: P2ValidationSet

8. EIS 1.19 Changes Review by Section • 5.3.1.1 updated the MMS alerts – • Added DRUC-CLOSE-NOTF • 12.3.1 – Verbal Dispatch Instructions (VDI):  MMS5 • Made “currentOprLevel” and “resource” elements optional • Added “finalOprLevel” and “finalState” elements • 10.2. – Resource Parameters –  MMS5 • Introduced cancel operation for Resource Parameters Set • Separated out the change/get/cancel operations in the EIS • Corrected “get” and “cancel” interfaces for resource parameter interfaces to use Request/ID=mRID instead of the payload.

9. Comments / Questions Received Review Comments / Questions Received

10. EIS Market Information Services Update: Background – Web Services Review • Then: External Interfaces Specification approved by TPTF in 2007 • Later: engagement with MIS and API Subgroups; Current Day Reports project changed implementation approach • New requirements were introduced (sometimes without protocol traceability) for displays; subsequently not needed as approach changed • Other reports turned out to be incompatible with web services • Issue with sizes and generating frequency of reports to be provided over API

11. EIS Market Information Services Update: Interface Review • Total of 19 items from the Market Information section of the document (read-only interfaces) that are being removed • These are items that are not suitable to be provided via web services for various reasons • Almost all are available through other means; the four items that are not were removed due to lack of protocol traceability • Currently shown highlighted in gray in the posted version – will be deleted in final posting of v1.19

12. EIS Market Information Services Update: Interface Review ~135 External Interfaces 51 Market Info interfaces 19 reclassified 4 not in protocols 5 ‘Get Report’ 3 other reports 7 MIS Displays • See accompanying spreadsheet for detail • ERCOT Market Information List (EMIL) located at http://nodal.ercot.com/readiness/reports/index.html under Key Documents titled “MIS - ERCOT Market Information List v8.09”

13. Q&A Q&A