Monthly Regulation Deployment Analysis –

August ‘12

September QMWG

Assumptions• The analysis presented here was done using 5 minute

average, maximum and minimum data• For these purposes, the term “regulation deployed” refers to

the total amount of regulation that was requested by ERCOT from the various QSEs and does not necessarily imply that the energy was realized

• Load and wind volatility for a given interval was calculated as the difference between the average value for that interval and the average value for the previous interval

• It should be noted that in the context of this analysis, “deviation” does not necessarily indicate that a Market Participant is behaving incorrectly– A WGR may “deviate” from expected during periods in which the weather

is changing rapidly– A thermal generator may “deviate” from expected when shutting down as

a result of the non-optimal method in use during the analysis period

2

Statistics for Whole of Month

3

CategoryAll

Intervals

Hours Ending 3

thru 6

Hours Ending 7 thru 14

Hours Ending 15 thru

18

Hours Ending

19 thru 2

Average Regulation Deployed (MW) 48 -31 41 113 64

Average Regulation Up Deployed (% of Requirement) 16.8% 13.3% 17.6% 19.1% 16.5%

Average Regulation Down Deployed (% of Requirement) 11.4% 17.7% 13.4% 7.0% 8.5%

Average Frequency (Hz) 60.000 60.001 60.000 60.000 59.999

Total Number of Intervals 8928 1488 2976 1488 2976

Total Number of Intervals During Which Only Reg. Up Deployed 3986 300 1323 983 1380

Total Number of Intervals During Which Only Reg. Down Deployed 2142 596 726 161 659

Average Gen. Deviation (MW) -43 32 -69 -111 -21Average Gen. Deviation for Resources with Base-Points Near or Above HSL - Non-

Wind (MW) -61 -9 -51 -125 -67

Average Gen. Deviation for Resources with Base-Points Near or Below LSL (MW) 35 50 59 21 12

Average Gen. Deviation Across Intervals During Which Only Reg. Up Deployed (MW) -150 -78 -181 -158 -131Average Gen. Deviation Across Intervals During Which Only Reg. Down Deployed

(MW) 111 98 104 51 145

Correlation Between Average Reg. Deployed and Average Gen. Deviation -0.819 -0.787 -0.824 -0.743 -0.857

Correlation Between Average Reg. Deployed and Average Gen. Deviation for Coal -0.466 -0.566 -0.389 -0.318 -0.517Correlation Between Average Reg. Deployed and Average Gen. Deviation for

Combined Cycles -0.703 -0.544 -0.708 -0.582 -0.716

Correlation Between Average Reg. Deployed and Average Gen. Deviation for Gas Steam- Not CC -0.411 -0.248 -0.474 -0.458 -0.367

Correlation Between Average Reg. Deployed and Average Gen. Deviation for Wind -0.223 -0.512 -0.250 -0.307 -0.305

Correlation Between Average Reg. Deployed and Change in 5 Min. Average Load 0.122 0.321 0.306 0.331 0.238

Correlation Between Average Reg. Deployed and Change in 5 Min. Average Wind -0.191 -0.454 -0.190 -0.338 -0.240

Statistics for Whole of Month

4

Statistics by Hour of the Day

5

Statistics by Hour of the Day and Fuel Type

6

Statistics by Hour of the Day for Resources Near Limits

7

Statistics by Day of the Month

8

Statistics by Day of the Month and Fuel Type

9

Statistics by Day of the Month for Resources Near Limits

10

Distribution of Frequency

11

Additional Tables

Statistics by Hour of the Day

13

Hour of Day

Average Reg.

Deployed (MW)

Average Reg. Up

Deployed (% of Req.)

Average Reg. Down Deployed

(% of Req.)

No. of Intervals Only Reg.

Up Deployed

No. of Intervals Only Reg.

Down Deployed

Average Gen. Deviation (MW)

All Resource Types

CoalCombined

Cycles

Gas Steam- Not CC

Wind

Resources with BP Near or

Above HSL- Non-Wind

Resources with BP Near or

Below LSL

1 42 11.5% 10.4% 138 98 -16 23 -41 4 -7 -41 112 -39 10.3% 18.7% 66 147 60 25 41 13 -23 -15 433 -29 13.8% 12.0% 76 140 46 21 41 10 -30 -11 444 -52 10.9% 20.9% 59 173 61 27 44 11 -25 -8 535 -37 14.4% 20.6% 70 158 35 8 40 10 -27 -7 536 -4 14.0% 17.2% 95 125 -12 -21 23 11 -30 -10 477 44 16.7% 10.3% 160 75 -28 -24 2 8 -20 -16 448 -21 12.3% 21.1% 95 141 5 -9 21 6 -21 -10 539 -2 12.4% 14.7% 139 111 -34 -49 26 10 -26 -20 67

10 20 16.7% 15.9% 151 118 -66 -63 -17 15 -6 -36 6711 30 16.7% 15.3% 157 106 -77 -62 -10 11 -23 -51 7812 61 17.7% 12.5% 180 75 -97 -57 -46 12 -11 -76 7413 88 21.5% 9.3% 216 54 -122 -56 -65 -5 -1 -89 5214 108 27.3% 7.9% 225 46 -136 -52 -69 -24 5 -108 3715 101 14.5% 7.5% 224 43 -118 -49 -65 -17 8 -119 3716 108 19.3% 8.5% 245 47 -109 -52 -65 -10 16 -125 2417 134 16.4% 5.8% 272 32 -128 -51 -69 -17 6 -132 1618 106 26.3% 6.2% 242 39 -88 -48 -56 11 7 -124 719 97 20.9% 4.8% 212 48 -70 -48 -42 16 5 -105 420 96 18.8% 6.9% 217 54 -50 -43 -34 19 9 -94 221 135 26.3% 4.2% 250 32 -106 -55 -61 4 5 -94 122 50 14.7% 7.3% 157 93 18 -36 -2 27 27 -71 223 107 19.8% 6.2% 195 82 -35 -23 -63 29 19 -66 324 21 9.5% 9.9% 145 105 35 22 -16 15 11 -48 27

Statistics by Day of the Month

14

Day of Month

Average Reg.

Deployed (MW)

Average Reg. Up

Deployed (% of Req.)

Average Reg. Down Deployed

(% of Req.)

No. of Intervals Only Reg.

Up Deployed

No. of Intervals Only Reg.

Down Deployed

Average Gen. Deviation (MW)

All Resource Types

CoalCombined

Cycles

Gas Steam- Not CC

Wind

Resources with BP Near or

Above HSL- Non-Wind

Resources with BP Near or

Below LSL

1 49 17.3% 13.5% 130 83 -40 -31 2 -9 3 -94 562 46 15.5% 11.4% 127 82 -37 -20 -20 4 3 -78 483 58 16.4% 9.9% 135 69 -52 -33 -22 6 -2 -69 464 86 20.6% 7.1% 150 43 -84 -37 -36 2 -12 -73 355 26 12.8% 10.7% 108 73 -36 -19 -21 13 -9 -34 276 63 17.9% 9.8% 126 59 -47 -35 -8 -8 1 -77 397 61 17.6% 10.9% 130 66 -69 -32 -22 -7 -5 -99 338 82 22.0% 6.6% 184 45 -79 -49 -18 11 -10 -82 229 118 23.7% 5.6% 177 33 -86 -40 -26 -7 -2 -93 3110 50 15.9% 9.8% 135 56 -79 -47 -31 13 -6 -96 3511 53 17.6% 11.0% 132 64 -30 -30 -6 11 3 -70 4612 47 16.1% 12.3% 128 71 -53 -38 -19 10 -11 -88 4513 66 19.8% 10.5% 153 54 -73 -45 -29 3 -10 -78 3214 35 14.1% 11.5% 126 69 -28 -38 -22 10 9 -68 4415 36 17.6% 14.3% 130 93 -17 -38 -9 20 -2 -53 4816 97 23.2% 5.6% 161 29 -99 -42 -53 4 -19 -44 2317 79 20.3% 11.2% 139 55 -84 -37 -58 5 -6 -64 2118 -7 13.4% 17.4% 90 110 -24 -11 -6 12 -26 -34 2419 66 20.6% 10.8% 120 74 -22 -16 -2 16 -28 -37 2620 28 14.0% 10.8% 110 79 -14 -21 -17 11 4 -48 3521 -40 8.7% 22.1% 68 122 39 -14 34 20 -5 -23 4922 10 11.5% 13.2% 99 89 28 -11 13 14 8 -31 4223 -20 9.6% 20.6% 86 109 78 -21 71 13 6 -38 5724 5 12.6% 14.4% 95 73 -42 -20 -42 6 4 -46 3725 -24 9.6% 20.0% 68 105 10 -11 14 7 -10 -25 4226 22 14.7% 13.7% 114 76 -24 -19 -6 8 -16 -37 3627 50 15.5% 11.2% 121 68 -42 -24 -33 18 -10 -52 4328 43 13.6% 10.0% 121 66 -53 -16 -54 16 -6 -59 2729 91 20.7% 6.6% 166 50 -85 -21 -77 10 -5 -70 1630 117 24.8% 7.2% 187 53 -102 -17 -67 -17 -10 -77 1431 109 22.4% 4.4% 170 24 -89 -35 -56 1 -5 -68 18