impact of nprr 520 (sced cct)

Sep 4, 2013

Impact of NPRR 520 Impact of NPRR 520 (SCED CCT)(SCED CCT)

Market AnalysisERCOT

Background of NPRR 520 (SCED CCT)

Why Change?Why Change? SCED over-mitigation issues

What Changed?What Changed? No Monthly and Daily Constraint Competitiveness Test (CCT) SCED CCT runs every 5 minutes (or whenever SCED is

executed) Less set of Resources get mitigated Minimizing unnecessary Base Point oscillations/QSGR dispatch

System Lambda Increase

Mitigation Ratio

Increased Peaker Net Margin (PNM)

Pivotal Players For Each Active Constraint (7/1-7/30) (Continued)

Pivotal Players For Each Active Constraint (7/1-7/30) (Continued)

Top 10 Non-Competitive Constraints

Constraints with Both Competitiveness Status (7/1-7/30)

CONTINGENCONTINGENCY_NAMECY_NAME

CONSTRCONSTR_NAME_NAME

FROM_SFROM_STATIONTATION

TO_STTO_STATIONATION

FROM_SFROM_STA_KVTA_KV

TO_STTO_STA_KVA_KV

CCT_SCCT_STATUSTATUS

CompetitivCompetitive_Freqe_Freq

NonCompetitNonCompetitive_Freqive_Freq

DENTSCS5 1170__A NCDSE HNRSW 138 138COMP 29 6

DGIBSNG5 240__A JEWET SNG 345 345COMP 26 29

DGIBSNG5 260_A_1 JEWET SNG 345 345COMP 77 18

DJEWSNG5 JK_TOKSW_1 TOKSW JK_CK 345 345COMP 325 30

DNAVWTR5 35040__A NAVARRO VENSW 345 345COMP 2 8

DTB_SNG5 SNGZEN99_A SNG ZEN 345 345COMP 6 926

Summary of Impact of NPRR 520

Average number of mitigated resources for each SCED interval:

Old: 100% vs. New: 4.8%  Average system lambda increase: $0.2/MWh for 744 hours.  Cumulative PNM increase: $80.63/MW.  Total number of non-competitive constraints:  Old: ~100% vs. New: 95%

Next Step

•Shall we use HDL instead of HSL for CCT calculation?

•Shall we include all online Resources’ LDL as base load?

•Shall we use sf*HSL instead of sf*sf*HSL for ECI calculation?

Thanks!Thanks!