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Nodal Telemetry Outreach and

Recent Changes to Focused Input Testing (FIT)

NATFSep 29, 2009Stacy Bridges, ERCOT

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• Recent Changes to FIT Testing• Nodal Telemetry Outreach• Remaining FIT III Windows in 2009

Nodal Telemetry Outreach and Recent Changes to FIT Testing

Texas Nodal

ERCOT discontinued making ERCOT-side Manual Replacements (MRs) during the FIT III Week 15 Window (Sept 8 – 10).

During the first two days of the test (Sep 8, 9), ERCOT provided ERCOT-side MRs to support State Estimator solutions.

On the third day of the test (Sep 10), ERCOT discontinued MRs (see details on next slide).

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Recent Changes to FIT Testing

Texas Nodal

On Sept 10, ERCOT discontinued ERCOT-side MRs for the first

time during a FIT window.

The ERCOT State Estimator (SE) continued to solve during test

hours with convergence rates comparable to those achieved

during previous FIT windows.

Factors contributing to this success included:

Code enhancements that deployed to the Nodal production

environment in August

ICCP updates that were recently submitted by Market

Participants (MPs)

Robustness of the SE software

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Recent Changes to FIT Testing

On Sept 10, ERCOT discontinued making MRs for Nodal telemetry.

The SE convergence performance on Sept 10 promoted confidence that the software

has matured to a point that ERCOT may continue to conduct future FIT windows

without the need to facilitate SE solutions via ERCOT-side MRs.

Texas Nodal04/19/23

FIT Series

Week Date Day 1 Day 2 Day 3 Convergence Avg % for all Test Hours

100% Convergence Achieved

FIT III Week 1 Feb 24 – 26, 2009 75.45 78.86 92.85 82.39 09 of 27 hrs

Week 2 Mar 10 – 12, 2009 96.82 92.97 98.41 96.07 20 of 27 hrs

Week 3 Mar 24 - 26, 2009 85.45 94.98 94.70 91.71 14 of 27 hrs

Week 4 Apr 07 - 09, 2009 97.13 92.60 97.44 95.72 21 of 27 hrs

Week 5 Apr 21 – 23, 2009 87.47 89.87 95.65 91.00 08 of 27 hrs

Week 6 May 05 – 07, 2009 94.34 94.47 91.87 93.56 13 of 27 hrs

Week 7 May 19 – 21, 2009 96.81 97.36 97.04 97.07 18 of 26 hrs*

Week 8 Jun 02 – 04, 2009 88.47 84.09 93.29 88.62 10 of 27 hrs

Week 9 Jun 16 – 18, 2009 97.45 86.14 95.59 93.06 13 of 27 hrs

Week 10 Jun 30 – Jul 2, 2009 94.91 89.89 86.66 90.49 11 of 27 hrs

Week 11 Jul 14 – 16, 2009 91.01 84.70 97.49 91.06 14 of 27 hrs

Week 12 Jul 28 – 30, 2009 95.91 94.73 93.66 94.77 18 of 27 hrs

Week 13 Aug 11 – 13, 2009 94.72 94.65 97.37 95.58 19 of 27 hrs

Week 14 Aug 25 – 27, 2009 96.51 93.25 99.07 96.28 21 of 27 hrs

Week 15 Sep 08 – 10, 2009 90.60 100 96.33 95.64 21 of 27 hrs

Week 16 Sep 22 – 24, 2009 89.42 99.07 96.30 94.93 20 of 27 hrs

Recent Changes to FIT Testing – FIT III Trends to Date

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* One hour was removed from the Week 7 test results to accommodate a nodal database load. No Manual Replacements

Recent convergence percentages provide a good indication of SE solution capability, but more work is still needed in the areas of missing unit telemetry and measurement quality.

Texas Nodal

To date, the outreach effort has focused primarily on Market Participants who were missing the largest share of ICCP points in Nodal.

ERCOT teams are now preparing to work with MPs to address a broader scope of missing points and to clean-up issues.

The ERCOT Advanced Network Applications, ICCP, Client Services, and EDS teams have scheduled a series of weekly internal meetings through the end of 2009 to discuss outreach progress and to coordinate follow-ups with MPs.

Follow-ups include specific open ICCP issues that will be routinely communicated with MPs on an individual basis and coordinated with the FIT windows.

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Nodal Telemetry Outreach

ERCOT began a Nodal Telemetry Outreach on August 31, 2009 to help MPs to correct Nodal telemetry issues in time for market trials.

Texas Nodal

As the telemetry outreach effort progresses, the quality of measurements used in each SE solution is expected to improve, along with overall confidence in SE solutions.

Information regarding the outreach effort and upcoming FIT windows will continue to be communicated via market notices, stakeholder meetings, and the regularly scheduled EDS market calls (http://www.ercot.com/committees/nodal/eds/).

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Nodal Telemetry Outreach

MPs may submit questions about the telemetry outreach to EDS3@ercot.com with “Nodal Telemetry Outreach” in the subject line.

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The 2009 FIT III Calendar and FIT III Assessment reports are posted at: http://nodal.ercot.com/readiness/eds3/documents/index.html

Remaining FIT III Windows in 2009

Remaining FIT III Windows in 2009

Name of FIT III Test Testing Dates Publishing Dates for FIT Report

FIT III, Wk 17 Oct 06 – 08 Oct 20

FIT III, Wk 18 Oct 20 – 22 Nov 03

FIT III, Wk 19 Nov 03 – 05 Nov 17

FIT III, Wk 20 Nov 17 – 19 Dec 01

FIT III, Wk 21 Dec 01 – 03 Dec 15

FIT III, Wk 22 Dec 15 – 17 Jan 03