QSE Managers Working QSE Managers Working GroupGroupMeeting NotesMeeting Notes

November 10, 2009November 10, 2009

Report to WMS Report to WMS November 18, 2009November 18, 2009

Jennifer Troutman – Vice ChairJennifer Troutman – Vice Chair

QSE Managers Working Group QSE Managers Working Group Topics Topics

Wind Plant Availability WebsiteWind Plant Availability Website Wind Generation Forecast Accuracy AnalysisWind Generation Forecast Accuracy Analysis Ancillary Services Procurement MethodologyAncillary Services Procurement Methodology Load Forecasting AccuracyLoad Forecasting Accuracy Decommitment Process for RPRS Decommitment Process for RPRS

Wind Plant Availability WebsiteWind Plant Availability Website Approximately 30 users are entering outagesApproximately 30 users are entering outages

Difficult to determine how many Market Difficult to determine how many Market Participants that translates intoParticipants that translates into

Some Market Participants reporting that the Some Market Participants reporting that the AWS outage scheduler can only be used for AWS outage scheduler can only be used for one hour at a timeone hour at a time For example, for an outage for HE 2-10, 9 For example, for an outage for HE 2-10, 9

separate outages would have to enteredseparate outages would have to entered ERCOT going to perform high level review ERCOT going to perform high level review

whether data is improving forecastwhether data is improving forecast

WGRPP Forecast Accuracy WGRPP Forecast Accuracy AnalysisAnalysis

ERCOT is now receiving good MET ERCOT is now receiving good MET data for all points from over 50 WGRsdata for all points from over 50 WGRs Additional improvement and increase in Additional improvement and increase in

the number of points being submittedthe number of points being submitted ERCOT was to analyze impact of ERCOT was to analyze impact of

moving from a P80 to P50 moving from a P80 to P50 Some members may draft PRR to at least Some members may draft PRR to at least

change to a P50 forecast in the on peak change to a P50 forecast in the on peak hours hours

WGRPP Forecast Accuracy WGRPP Forecast Accuracy AnalysisAnalysis

Based on Day Ahead resource plans submitted by QSE’s compared to aggregate WGRPP AWS forecast in order to scale the STWPF.

 

 Mean Actual

Estimated Output

Standard Deviation of Estimated Output **

Mean Absolute MW Error

(Abs(Estimated Output - Scaled

STWPF))

Mean Absolute Percent Error

(Output in Denominator) - (Abs(Estimated Output - Scaled

STWPF)/Estimated Output) *

Mean Absolute Percent Error (Capacity in

Denominator) - (Abs(Estimated Output - Scaled STWPF)/Total

Name Plate WGR Capacity)

All Hours 1816.14 1423.04 697.45 92.87% 8.24%

Off-Peak Hours (1-6,23,24) 2230.68 1566.33 873.05 126.45% 10.30%

On-Peak Hours (7-22) 1608.87 1298.61 609.64 76.07% 7.20%

Hour Ending 23-24 and 1-2 2339.49 1546.13 986.71 92.78% 11.64%

Hour Ending 3-6 2121.86 1585.23 759.39 160.13% 8.97%

Hour Ending 7-10 1743.41 1428.61 627.85 110.94% 7.42%

Hour Ending 11-14 1454.21 1364.51 460.85 74.02% 5.45%

Hour Ending 15-18 1444.21 1140.44 583.86 56.68% 6.91%

Hour Ending 19-22 1793.64 1216.77 766.02 62.65% 9.04%

September Data in HistogramSeptember Data in Histogram

Risk of Over CommitmentRisk of Shortages

WGRPP ForecastWGRPP Forecast

ERCOT is now providing the forecast ERCOT is now providing the forecast to WGRs via XMLto WGRs via XML

ERCOT going to issue notice soon that ERCOT going to issue notice soon that it will discontinue providing it via emailit will discontinue providing it via email

ERCOT Client Services going to poll ERCOT Client Services going to poll WGRs to be sure that no one is still WGRs to be sure that no one is still using email processusing email process

Load Forecast AnalysisLoad Forecast Analysis

QMWG going to work with ERCOT to QMWG going to work with ERCOT to schedule Load Forecasting Workshop schedule Load Forecasting Workshop Will coordinate efforts with the PUCTWill coordinate efforts with the PUCT

Reviewed ERCOT’s Replacement Reviewed ERCOT’s Replacement Reserve Service Monthly ReportsReserve Service Monthly Reports Going to ask ERCOT SME to review in detail Going to ask ERCOT SME to review in detail

at next meeting at next meeting

Load Forecast AccuracyLoad Forecast Accuracy

Load Forecast AccuracyLoad Forecast Accuracy

Hours Ending All Days

By Season By Year Last 4 Months

December,

January, Februar

y

March, April, May

June, July,

August

September,

October, Novemb

er

2007 2008 2009 July '09

August '09

September '09

October '09

23-24 and 1-2 3.06% 3.33% 2.48% 3.43% 2.94% 3.30% 3.00% 2.93% 3.01% 3.92% 3.09% 2.66%

3-6 2.50% 3.77% 1.96% 2.15% 2.43% 2.19% 2.70% 2.50% 1.96% 2.60% 1.84% 2.69%

7-10 2.76% 3.71% 2.60% 2.23% 2.77% 2.48% 2.99% 2.70% 2.04% 1.92% 2.02% 2.75%

11-14 3.50% 4.84% 3.34% 2.76% 3.49% 3.51% 3.62% 3.35% 2.54% 2.17% 4.02% 2.75%

15-18 4.08% 3.95% 3.68% 4.24% 4.34% 4.84% 3.81% 3.78% 3.49% 3.31% 6.20% 3.57%

19-22 4.09% 3.21% 3.72% 4.97% 4.09% 5.15% 3.66% 3.76% 3.99% 4.50% 4.92% 3.09%

All Hours 3.33% 3.80% 2.96% 3.30% 3.34% 3.58% 3.30% 3.17% 2.84% 3.07% 3.68% 2.92%

Decommitment Process for RPRSDecommitment Process for RPRS

ERCOT is drafting PRR language for thisERCOT is drafting PRR language for this Operations SupportOperations Support SettlementsSettlements

Market Participants want to focus efforts Market Participants want to focus efforts on creating a Nodal decommitment on creating a Nodal decommitment processprocess

Next MeetingNext Meeting

Next Meeting: December 2, 2009Next Meeting: December 2, 2009 TopicsTopics

Wind Generation Forecast AccuracyWind Generation Forecast Accuracy Load Forecasting AccuracyLoad Forecasting Accuracy Nodal Decommitment Process for RUCNodal Decommitment Process for RUC Wind Generation Nodal IssuesWind Generation Nodal Issues