PRR 730 Option Review

ERCOTQSEPM September 5, 2007

Option Summary

• Option 1 – increase the load by the LSL amount of all units procured through RPRS and OOMC and then re-run BES market

• Option 2 – same as Option 1 with an additional step that compares MCPE with Max Energy Bid. Add the amount of LSL to HSL for those units that have a bid amount less than MCPE.

• Option 3 – Legal Review

RPRS Procurement - Option 1

UNITNAME MINUP MINDN MINMW MAXMW 12 13 14 15 16 17 18 19 20 21 22 23 24

xxxx_1 4 4 10 60 - - S1 S1 S1 S1 - - - - - - -

xxx_2 4 4 10 61 - - - - - S1 S1 S1 S1 - - - -

xxx_3 4 7 10 26 - S1 S1 S1 S1 S1 S1 S1 - - - - -

xxx_4 2 2 0 154 - - - ss ss S2 ss - - - - - -

xxxx_6 1 2 46 165 - - - S2 S2 S2 - - - - - - -

xxx_7 4 2 70 140 - - - S2 S2 S2 S2 - - - - - -

Xxxxx_8 1 2 24 75 - - - - - S2 S2 - - - - - -

Xxxx_9 1.5 1 0 41 - - - - - S2 S2 - ss - - - -

Xxxx_10 1 3 175 175 - - - S2 S2 S2 S2 - - - - - -

Xxxxx_11 1 2 15 174 - - - - - S2 - - - - - - -

Xxxxx_12 4 4 28 167 - - - S2 S2 S2 S2 - - - - - -

xxxx_13 4 4 2323 176 ss ss ss ss ss ss S2 - - - - - -

Xxx_14 1 8 124 807 - - - - S2 S2 - - - - - - -

Xxxx_15 1 8 0 28 ss ss ss ss ss ss ss ss ss ss ss ss ss

Interval 1700 Studied

• Original MCPE = $58.38• 512 MW of RPRS between zero and LSL• Load forecast raised by 512 MW and SPD re-run

Original Forecast

• COAST 15525• EAST 2322• FAR_WEST 1240• NORTH 1787• NORTH_C 18638• SOUTHERN 3808• SOUTH_C 8025• WEST 1694• TOTAL 53039

Modified Forecast

• COAST 15525 + 512 = 16037

• EAST 2322• FAR_WEST 1240• NORTH 1787• NORTH_C 18638• SOUTHERN 3808• SOUTH_C 8025• WEST 1694• TOTAL 53551

Results

• MCPE with forecast raised 512 MW = $59.67

• Study time approximately 15 minutes if no NSRS deployment

• 8 hours of RPRS procurement

• 32 intervals would require approximately 480 minutes

• Review would require an independent running of this procedure and an additional run for every interval in which NSRS is deployed.

ERCOT Comments

• Option 1 & 2 – RPRS and OOMC are not considered to be instructed deviations. A QSE is not required to modify their schedules for RPRS or OOMC procurements. NSRS, when deployed, is an instructed deviation and will reduce the amount of BES Up required. The addition of RPRS & OOMC will increase the amount of MWs offered into the BES market but will not affect the BES requirement in the same manner as NSRS.

Estimate of Impact of Proposed Options

• Option 1& 2 – Manual determination of the number of intervals and units that will be affected by RPRS and OOMC. Multiple runs may be required for NSRS affected intervals. Estimate of 2 FTEs required to support effort.

• Options can not be executed if zonal congestion exists or if the re-run of BES results in zonal congestion.