1. Lead from the front Texas Nodal http://nodal.ercot.com 1 EDS 3 R6.2 Testing Overview Texas Nodal Load Frequency Control (LFC) EDS 3 Release 6 LFC WebEx February 27, 2008

2. Lead from the front Texas Nodal http://nodal.ercot.com 2 LFC – R6.2: LFC Testing for Individual QSEs Presentation – Overview Staffing for Testing Test Procedure VDI Example 5 Minute Base Point Submittal QSE Resource Information Submittal ICCP Data from QSE Pre-Test Verification Walkthrough Test Example QSE Submittal Summary

3. Lead from the front Texas Nodal http://nodal.ercot.com 3 LFC – R6.2: Overview Overview – –Testing (including Pre-Test) performed March to June –ERCOT will verify that each QSE and its Resource(s) has the ability to follow Nodal Regulation instructions. –ERCOT will verify that each QSE and its Resource(s) has the ability to follow the Nodal Updated Desired Base Point instructions. –ERCOT will verify Resources follow the QSE provided Regulation Participation Factor. Test Period for Regulation and Updated Desired Base Point verification will be at least 1 hour. –ERCOT will verify for each QSE the ability to operate on constant frequency control when requested by ERCOT. Test Period for constant frequency control is approximately 15 minutes –ERCOT will verify QSE ability to update their Responsive Reserve Schedule(s) in response to a Responsive Reserve Deployment.

4. Lead from the front Texas Nodal http://nodal.ercot.com 4 LFC – R6.2: Staffing for Testing Staffing at ERCOT – –ERCOT System Shift Supervisor –ERCOT System Operator (Frequency Desk) –ERCOT Operations Planning Engineers –ERCOT EMS Support Engineers –QSE Test Representative (knowledge of LFC, EMS, SE, Operations) Staffing at QSE Control – –QSE LFC Testing Group –QSE EMS Support –QSE Operators

5. Lead from the front Texas Nodal http://nodal.ercot.com 5 LFC – R6.2: Test Procedure Test Procedure – ERCOT Control Room Procedure for LFC R6.2 Test available

6. Lead from the front Texas Nodal http://nodal.ercot.com 6 LFC – R6.2: VDI Example VDI Example –

7. Lead from the front Texas Nodal http://nodal.ercot.com 7 LFC – R6.2: 5 Minute Base Point Submittal 5 Minute Base Point Submittal – ERCOT will provide an EXCEL spreadsheet for QSE to populate with Resource Specific 5 Minute Base Points Each Resource involved in the test must be included in the spreadsheet The Base Points must be provided for the hour before, during and after the actual scheduled one hour test time. The file format will be provided by ERCOT, and will be a CSV file. The QSEName, PlantName, UnitName must match the naming used in the ERCOT database. ERCOT will provide this information in the file.

8. Lead from the front Texas Nodal http://nodal.ercot.com 8 LFC – R6.2: 5 Minute Base Point Submittal 5 Minute Base Point File Format –

9. Lead from the front Texas Nodal http://nodal.ercot.com 9 LFC – R6.2: QSE Resource Information Submittal QSE Resource Information Submittal Template – QSE will work with ERCOT to provide the necessary Resource information for the test. This will most likely be a template form for the QSE to fill in. This information is required to help the QSE and ERCOT to formulate expected results prior to the testing. The Resource Information should be submitted at least 2 business days before the R6.2 Pre-test, and at least 5 business days before the R6.2 test. The template information for each Resource in the test will include: Resource Name Resource Status Code change during the 3 hours Resource Ancillary Services for the 3 hours, including any changes Resource Participation Factors for the 3 hours, including changes Resource’s HEL, HSL, LSL, LEL and Ramp Rate data (RARF)

10. Lead from the front Texas Nodal http://nodal.ercot.com 10 LFC – R6.2: ICCP Data from QSE QSE ICCP Data Required – The following data provided by ALL QSEs for ALL Resources must be valid (mid March 08) and reflect Zonal real time to enable LFC R6.2 testing to occur. This data will be verified in the Pre-Test activities. -Resource Output (MW) and/or Net Power Flow (NPF) -Resource Status Code (RST) -Combine Cycle Configuration (CCC) -Dynamic Schedule Resource (DSRS) -HEL and LEL -HSL and LSL -Regulation Up Responsibility -Regulation Down Responsibility -Regulation Participation Factors -Responsive Reserve Responsibility and Schedules -Non-Spin Reserve Responsibility and Schedules -Lower and Raise Block Status (LBST and RBST)

11. Lead from the front Texas Nodal http://nodal.ercot.com 11 LFC – R6.2: Pre-Test Verification R6.2 Pre-Test– The R6.2 pre-test will validate that the necessary data and processes in preparation for the R6.2 test. QSE Submit 5 Minute Base Point file in correct CSV format QSE Submit the Resource Information as per template provided Resources follow Zonal dispatch instructions during Pre-Test Validate QSE ICCP data Verify ERCOT and QSE Resource mapping correct Verify ERCOT’s 5 minute Base Point file process Verify VDI process Walkthrough the R6.2 Test procedure R6.2 Pre-Test conducted at least two weeks before R6.2 Test to allow time to address any outstanding issues

12. Lead from the front Texas Nodal http://nodal.ercot.com 12 LFC – R6.2: QSE Submittal Summary QSE Submittal Data for R6.2 – QSE and Resource ICCP Data (reflecting Zonal real time) 5 Minute Base Point file submitted 2 days before R6.2 Pre-test Resource Information submitted 2 days before R6.2 Pre-test 5 Minute Base Point file submitted one day before R6.2 test and can be updated up to 30 minutes before the scheduled R6.2 test. Resource Information submitted 5 days before R6.2 test Note: QSE’s with only Wind Resources are required to participate in the R6.2 Pre-test. They are not required to participate in the R6.2 test. The QSE will verify their Nodal system readiness by providing ERCOT with relevant time stamp data and system screen captures.

13. Lead from the front Texas Nodal http://nodal.ercot.com 13 LFC – R6.2: Questions? Thank you. LFC@ercot.com