1. RMR Exit for Spencer 5 – Remedial Action Plans
Chris Ngai
Jay Teixeira
Regional Planning Group
April 16, 2010

2. Summary
ERCOT staff analysis of the Spencer 5 exit from RMR status indicated that the Remedial Action Plans (RAPs) described herein would facilitate the unit’s RMR exit. Slide 3 contains a list of the six RAPs proposed as an RMR exit strategy for Spencer 5 with detailed descriptions of the RAPs in the subsequent slides.
Review of the RAPs submitted by Oncor on April 14 is currently in progress. RAPs were revised to take into account current construction activity.
This analysis was performed using the 2010 summer peak case; last updated on December 11, 2009.

3. List of RAPs RAP Description Contingency/Overload pair Est. Hours/yr*1
Carrollton RAP
L: Lewisville Switch (645)-Highland E 138kV(1970) line
C: Lewisville Switch (645)-Highland(664)
613
C: Highland (664) - Canyon (668) 7 2
Lake Pointe RAP
L: Carrollton Northwest-LakePointe 138kV line
C: Lewisville Switch 345/138kV autotransformer
208** 3
Highland RAP
L: Lewisville Switch (645)-Highland E 138kV(1970) 138kV line
C: Coppell-Lewisville Switch 10 4
Frisco RAP
L: Collins (2370) to Frisco (681) 138kV line
C: Denton Steam – Corinth; Teasley to Pockrus
278 5
Frisco Voltage RAP
L: Low voltage at Frisco and Panther Creek
C: Collin to Frisco 138kV line 90 6
Arco RAP
After Operation of Carrollton RAP or Lake Pointe RAP
See above
*based on SSWG load level and one unit unavailable
**138 kV line from NW Carrollton to Lewisville still in service through summer this RAP not needed

4. RAP 1 – Carrollton RAP
Problem 1
Contingent element: Lewisville Switch (645)-Highland(664)
Overload element: Lewisville Switch (645)-Highland E 138kV(1970) line (Rate A/B/C: 214/214/214)
RAP operation: Open NW Carrollton (2361) – Lewisville Switch (646) 345kV and 138 kV lines
Level of overload: 117.8% Rate B (252.1MVA)
Estimated number of hours RAP would operate in year 2010: 613 hours

5. RAP 1 – Carrollton RAP cont’d
613 hours
Contingency:
Lewisville Switch (645) to Highland E (1970) 138kV line
Overload element:
Lewisville Switch (645) to Highland (664) 138kV line
RAP action:
Open the NW Carrollton (2361) –
Lewisville Switch (646) 345kV line
Denton
NW Carrollton
Roanoke

6. RAP 1 – Carrollton RAP cont’d
Problem 2
Contingent element: Highland (664) - Canyon (668)
Oveload element: Lewisville Switch (645)-Highland E 138kV(1970) line (Rate A/B/C: 214/214/214)
RAP operation: Open the NW Carrollton (2361) – Lewisville Switch (646) 345kV and 138 kV lines
Level of overload: 101.9% Rate B (218.1MVA)
Estimated number of hours RAP would operate in year 2010: 7 hours

7. RAP 1 – Carrollton RAP cont’d
7 hours
Contingency:
Highland (664) to Canyon (668) 138kV line
Overload element:
Lewisville Switch (645) to Highland E (1970) 138kV line
RAP action:
Open the NW Carrollton (2361) –
Lewisville Switch (646) 345kV line
NW Carrollton
Roanoke
Denton

8. Contingent element: Lewisville Switch (645)-Highland(664)
RAP 2 – Lake Pointe RAP
Contingent element: Lewisville Switch (645)-Highland(664)
Overload element: Lewisville Switch 345/138kV autotransformer (Rate A/B/C: 700/700/700)
RAP operation: Open the line TNMP Lake Pointe (37010) – TNMP Lewisville (37080)
Level of overload: 113.3% Rate B (317.3MVA)
Estimated number of hours RAP would operate in year 2010: 208 hours
Not needed in 2010 summer due to 138 kV line from Lewisville to NW Carrollton line being in case
May activate Arco RAP to handle Double Circuit contingency
Causes Collin to Frisco to overload

9. RAP 2 – Lake Pointe RAP cont’d
208 hours
Contingency:
Lewisville Switch 345/138kV autotransformer
Overload element:
Carrollton Northwest –
Lake Pointe 138kV line
RAP action:
Open the line TNMP Lake Pointe (37010) –
TNMP Lewisville (37080)
Denton
NW Carrollton

10. Contingent element: Coppell-Lewisville Switch
RAP 3 - Highland RAP
Contingent element: Coppell-Lewisville Switch
Overload element: Lewisville Switch (645)-Highland E 138kV(1970) 138kV line (Rate A/B/C: 214/214/214)
RAP operation: Open Lewisville Highlands (37050) – Lewisville West (37060)
Level of overload: 101.8% Rate B (217.8MVA)
Estimated number of hours RAP would operate in year 2010: 10 hours
Coppell to Lewisville Switch contingency sectionalized to Lewisville Switch to Lewisville.
Overload element: Coppell Tap to McKamy Tap
May not related to Spencer RMR

11. RAP 3 - Highland RAP cont’d
10 hours
Denton
Contingency:
Coppell to Lewisville
Switch 138kV line
Overload element:
Lewisville Switch (645) - Highland E (1970) 138kV line
RAP action:
Open Lewisville Highlands (37050) – Lewisville West (37060)
NW Carrollton

12. Contingent element: Denton Steam – Corinth & Teasley - Pockrus
RAP 4 – Frisco RAP
Contingent element: Denton Steam – Corinth & Teasley - Pockrus
Overload element: Collins (2370) to Frisco (681) 138kV line (Rate A/B/C: 256/256/256)
RAP operation:
Raise the voltage of the West Denton 138kV side to 140kV
Modify the Collin Switch Reactor SPS so that it will operate when the Collin to Frisco line overloads.
If this does not resolve the overload, put all three capacitor banks at Navo in-service
Verify Argyle and Corinth capacitors are on
Level of overload: 109% Rate B (276.9MVA)
Estimated number of hours RAP would operate in year 2010: 278 hours

13. RAP 4 – Frisco RAP cont’d 278 hours Collin North Denton Spencer
Contingency:
Denton Steam auto-transformer to Corinth &
Teasley to Pockrus 138kV line
Overload element:
Collins (2370) to Frisco (681) 138kV line
RAP action:
Raise the voltage of the
West Denton 138kV side
to 140kV
Collin Switch Reactor SPS operates
when the Collin to Frisco line
overloads
put all three capacitor
banks at Navo in-service
Collin
North Denton
Spencer

14. RAP 5 - Frisco Voltage RAP
Contingent element: Collin to Frisco 138kV line
Low voltage element: Frisco and Panther Creek bus
RAP operation:
Raise voltage at West Denton to 1.02~1.05
adjust power factor/load
Level of overload: p.u.
Estimated number of hours RAP would operate in year 2010:
<0.92 p.u. – 584 hours (Brazos Criteria)
<0.90 p.u. – 90 hours (ERCOT Criteria)

15. Carrollton RAP (line loadings refer to Collin to Frisco)
RAP 6 – Arco RAP
Cause
Carrollton RAP
Lake Pointe RAP
Overload element: Collin (2370) to Frisco (681) 138kV line (Rate A/B/C: 256/256/256)
RAP operation: Open Arco (1993) – Krugerville (1994)138kV line
Level of overload:
Carrollton RAP (line loadings refer to Collin to Frisco)
Problem % (239.4 MVA) after Carrollton RAP [pre RAP: 104.1% MVA Collins SPS would relieve this but not after Carrollton RAP so should use Arco RAP instead]]
Problem 2 – 113.8% (291.4 MVA) after Carrollton RAP [pre RAP: 102.3% MVA Collins SPS would relieve this but not after Carrollton RAP so should use Arco RAP instead]]
Lake Pointe RAP % (284.6 MVA) after Lake Pointe RAP [pre RAP: 110.6% 283 MVA]

16. RAP 6 – Arco RAP cont’d Krugerville Navo Panther Creek Arco Collin
Same # of hours as
Carrollton RAP & Highland RAP
Overload element:
Collins (2370) to Frisco (681) 138kV line
Contingency:
overload caused by
Carrollton RAP and Lake Pointe RAP
RAP action:
Open Arco (1993) – Krugerville (1994)138kV line
Collin
Krugerville
Arco
Navo
Panther Creek

17. Permanent RMR Exit Solutions
Project
TPIT
Estimated Completion Date 1
RD Wells to Hickory 69kV (Denton)
06TPIT0198
(tier 4)
June 2010 2
Upgrade Lewisville Switch to Highland (TNMP) 138 kV line to 290MVA or above
07TPIT0018
May 2015 3
Add second 345/138kV autotransformer at Lewisville switching substation
07TPIT0042
(tier 3)
June 2011 4
Upgrade Collin to Frisco 138kV line to 326MVA
08TPIT0068
June 2013 5
Upgrade West Denton to Jim Christal to North Denton138kV line to 250 MVA or above
Per E. Schroeder (TMPA) dated 3/10/2010
Summer 2012 6
Additional capacitor banks at Navo and Panther Creek Substations (interim for Mustang capacitor bank)
2011 7
New Mustang Substation and capacitor bank
10TPIT0083 8
Upgrade Arco to Krugerville 138kV
10TPIT0032
May 2011

18. Questions?