1. ERCOT RMR Study for Luminant NSO
Jeff Billo
RPG Meeting
March 13, 2009

2. Luminant – Notice of Suspension of Operations
On February 5, 2009 Luminant submitted Notice of Suspension of Operations (NSO) for:
March 13, 2009
RPG Meeting

3. Luminant – Notice of Suspension of Operations
The units were grouped and analyzed in two group based on the proposed suspension dates
Group 1: May 2009
Group 2: September 2009
Analysis was done to determine if absence of the units violated any planning criteria as outlined in the Operating Guides
Transfer study performed using MUST
Voltage Stability study performed using VSAT
Study results were reviewed and verified by Operations Staff
March 13, 2009
RPG Meeting

4. Luminant – Notice of Suspension of Operations
The following study assumptions were used:
2009 summer peak case (SSWG DSA December 2008 Update) used for Group 1 units
All Group 1 units turned off
All Group 2 units were available (unless otherwise specified)
All wind generation was turned off
2010 summer peak case (SSWG DSB December 2008 Update) used for Group 2 units
All Group 1 and 2 units were turned off
For each unit a second scenario was modeled where a nearby unit was modeled as unavailable; for some units a third scenario was modeled where a different nearby unit was modeled as unavailable [to meet Operating Guide 5 requirements]
March 13, 2009
RPG Meeting

5. Luminant – Notice of Suspension of Operations
Justification for turning off wind generation in RMR analysis using 2008 wind data
348 hours when wind generation was less than 10% of installed capacity (roughly one hour each day)
179 hours when all wind generation in ERCOT was less than 30 MW total (roughly one hour every 2 days)
55 hours when all wind generation in ERCOT was less than 10 MW (roughly one hour each week)
1 hour when all wind generation in ERCOT was 0 MW
March 13, 2009
RPG Meeting

6. Luminant – Notice of Suspension of Operations
Permian Basin 5 Results
With a nearby unavailable the following constraints could not be resolved:
Transfer Limit
(MW)
Limiting Element
Limiting Contingencies
-483
Odessa (138/345) kV
Auto-transformer – 1
Auto-transformer – 2
-118
Ackerly Vealmoor – Ackerly
69 kV Line
Sharon Ridge – Bluff Creek
138 kV Line
March 13, 2009
RPG Meeting

7. Luminant – Notice of Suspension of Operations
Permian Basin 6 Results
The following constraints could not be resolved:
Transfer Limit
(MW)
Limiting Element
Limiting Contingencies
-56.1
1027 ODESEHV_ ODESEHV_ 345 1
1027 ODESEHV_ ODESEHV_ 345 2
412.3
March 13, 2009
RPG Meeting

8. Luminant – Notice of Suspension of Operations
Permian Basin 6 Results
With a nearby unit unavailable the following constraints could not be resolved:
Transfer Limit
(MW)
Limiting Element
Limiting Contingencies
-122.5
1356 ACKRLYVE ACKERLY_
1300 EXSHARNR BLUFCKTA 138 1
150.2
1362 ACKERLY_ ACKRLNTC
210.5
1300 EXSHARNR WILLOWVA 138 1
201.8
1308 GAILLYNT WILLOWVA 138 1
280.0
272.2
401.4
1363 ACKRLNTC SPARNBRG
409.9
1164 LAMESA_ SPARNBRG
1027 ODESEHV_ ODESEHV_ 345 1
1027 ODESEHV_ ODESEHV_ 345 2
346.1
459.2
1054 OLFNNSHL NYLONTAP 138 1
1051 HUNTSMAN REXALL_
269
1322 BIGSPRIG BIGSPGWE 138 1
1028 ODESEHV_ QUAILSW_ 345 1
1030 MRGNCRK_ LONGSHOR 345 1
March 13, 2009
RPG Meeting

9. Luminant – Notice of Suspension of Operations
Decordova Results
With a nearby unit unavailable the following constraints could not be resolved:
Transfer Limit
(MW)
Limiting Element
Limiting Contingencies
-981
2427 WATMLL_W TRINDAD
Limestone 345 kV to Water Mill 345 kV 1
Limestone 345 kV to Water Mill 345 kV 2
-57.2
3380 BIGBRN__ JEWETT_N 345 1
-287
2432 TRICRN1_ TRINDAD
228.5
2420 CHILSW1_ WATMLL_E 345 1
2398 WLEVEE1_ WATMLL_
2427 WATMLL_W SARGT1_
2427 WATMLL_W WATMLL_
473.1
1906 VENUS_S BIGBRN__ 345 1
March 13, 2009
RPG Meeting

10. Luminant – Notice of Suspension of Operations
Further analysis is being done to determine if Permian Basin 5, Permian Basin 6, and Decordova are needed as Reliability Must Run (RMR) units.
Uplan analysis being performed to determine if security constrained dispatch is possible
Working with Oncor to verify results and possibly determine if RAPs or SPSs can be developed to resolve constraints
Initial analysis determined that all other units proposed in the NSO did not qualify for RMR status.
March 13, 2009
RPG Meeting

11. Questions?
March 13, 2009
RPG Meeting