Entergy Gulf States, Inc. (Texas) Approved & Proposed Transmission Reliability Projects

1. Entergy Gulf States, Inc.(Texas)Approved & Proposed Transmission Reliability Projects Entergy/ETEC Subcommittee Meeting The Woodlands, TX November 28, 2006

2. Recap of 2004-06 EGSI-TX TransmissionWestern Region Reliability Improvement Plan: Phase II Scenario: • In 2003, several planning studies indicated the Western Region has the potential to encounter voltage stability problems and thermal overloading under the double contingencies listed below. • Loss of Lewis Creek Unit & 345 kV Line 119 (Crockett-Grimes) • Loss of Lewis Creek Unit & 230 kV Line 568 (China-Jacinto) • Loss of both Lewis Creek Units Recommended Solution: • Phase II of the Western Region Reliability Improvement Plan addresses the projected load growth with the following projects: • 500/230 kV Auto (Cypress) COMPLETED • Construct Line 822 (China-Porter) 230 kV COMPLETED • Construct 230/138 kV Porter Substation COMPLETED • Upgrade Line 599 (Amelia-China) 230 kV COMPLETED • Install 300 MVAr SVC at Porter Substation COMPLETED • Install series compensation on Line 822 (China-Porter) COMPLETED Estimated Cost: $115 MM

3. 2006 EGSI-TX Approved Transmission Reliability ProjectsWestern Region Phase II INSTALLED SERIES CAPACITOR ON LINE 822 INSTALLED 300 MVAr SVC

4. Approved 2007 EGSI-TXTransmission Reliability Projects inEntergy’s Construction Plan

5. Approved EGSI-TX Transmission Reliability Projects in Entergy’s Construction Plan • Others: • WRRIP- Phase 3 Scoping & Engineering • Upgrades of underrated breakers (various locations, mandatory-safety) • Splendora: Replace switch (mandatory-safety) Grimes: Reconfigure 345/138 kV Substation Calvert: Expand 69 kV Cap Bank Calvert Grimes Conroe Porter Tamina Helbig Amelia Porter-Tamina-Conroe: Upgrade 138kV Lines Hanks South Beaumont Kolbs & Hanks: Upgrade 230 kV Bus Kolbs Sandy Shores Beaumont 69 kV System Improvement Plan Sandy Shores: Add 69 kV Cap Bank

6. Grimes 345/138 kV Substation Reconfiguration Scenario: • 345/138 kV autotransformers tied to same node of 345 kV and 138 kV ring busses. • Single contingency loss of either 345/138 kV autotransformer causes the loss of the parallel autotransformer. Recommended Solution: • Install a 345 kV circuit breaker to separate autotransformers on 345kV ring and reconfigure station to alternate lines and loads. • Install 138 kV breaker to separate autotransformers on 138 kV ring. Estimated Cost: $0.5 MM (2007 cost only)

7. 2007 Grimes 345/138 kV Substation Reconfiguration RECONFIGURE 345 kV BUS CROCKETT 345kV INSTALL 345 kV BREAKER AUTO #1 FRONTIER 138kV AUTO #2 INSTALL 138 kV BREAKER

8. Hanks & Kolbs: Upgrade Substation Bus Scenario: • Firm load within the Port Arthur area has grown such that the Hanks and Kolbs substation through bus overloads under the loss of the Sabine to Mid County 230 kV line. Recommended Solution: • Upgrade limiting elements of substation bus at Hanks & Kolbs. Estimated Cost: $0.2 MM

9. Hanks & Kolbs: Upgrade Substation Bus Kolbs Hanks

10. EGSI-TX Circuit Breaker Upgrades Scenario: • Based on asymmetrical fault current analysis, various circuit breakers have been identified as underrated. Recommended Solution: • Replace the identified underrated circuit breakers with appropriately sized breakers. • 2006 • Cow 69kV #5515, #5510 • Orange 69kV #3165, 3145 • 2007 • Orange 69kV #3365 • South Beaumont 69kV #3700 • Port Neches 138kV #3345 • West End 69kV #22135 • 2008 • Orange 69kV #3370 • Dupont Bulk 69kV #3255, #3260 • Helbig 69kV #5585

11. EGSI-TX 69 kV System Voltage Support Calvert 69 kV Substation • Loss of 69 kV Line 159 (Bryan – APL Hearne) causes under-voltages at Calvert 69 kV Substation. • Expand existing capacitor bank to 12 MVAr • Approximate Cost: $0.6 MM Sandy Shores 69kV Substation • Multiple contingencies cause under-voltages on 69 kV Line 175 “Beach Line.” • Install 11 MVAr capacitor bank Estimated Cost: $0.5 MM

12. 2007 EGSI-TX 69 kV Voltage Support EXPAND EXISTING CAP BANK INSTALL 11MVAR CAP BANK

13. Porter-Tamina-Conroe:Upgrade 138 kV Lines 823 & 886 Scenario: • Lines 823 & 886 are 138 kV tie lines to the Western Region and the Conroe area specifically. • The loss of 138 kV Line 886 (Oak Ridge – Porter) overloads Lines 823 & 886 above their thermal limits. Recommended Solution: • Upgrade Line 886 (Tamina – Conroe) to 531 MVA capacity; replace switches and breaker at Tamina Substation to increase rating on the Porter-Tamina line segment. Estimated Cost: $5.5 MM

14. 2007 Porter-Tamina-Conroe:Upgrade 138 kV Lines 823 & 886 UPGRADE TO 531MVA CAPACITY

15. 69 kV Beaumont Network Upgrades Scenario: • In the 69 kV Beaumont area there exists several single contingency thermal overloads including: • 69 kV Line 581 (Helbig – Rosedale) • 69 kV Line 468 (Elizabeth – Gallier) • 230/69 kV Helbig Autotransformers • 69 kV Bus Tie Breakers (Helbig & Amelia) Recommended Solution: • Add line breakers at Yankee Doodle 69 kV Substation. • Close normally open points at Lincoln and Crockett 69 kV Substations. • Rebuild 69 kV Line 576 (Lincoln – South Beaumont) & 69 kV Line 98/190 (Dupont Beaumont – South Beaumont) to 106 MVA capacity. • Approximately 5.5 miles of 69 kV transmission lines Estimated Cost: $8 MM

16. 2007 69 kV Beaumont Network Upgrades CROCKETT CLOSE N.O. BREAKER CLOSE N.O. SWITCH YANKEE DOODLE L-155 VIRGINIA LINCOLN L-458 CARDINAL ADD LINE BREAKERS UPGRADE LINE 576 L-458 UPGRADE LINE 190 LAMAR CDT NITRO DUPONT BEAUMONT SOUTH BEAUMONT BULK UPGRADE LINE 98

17. 2010+ Western Region Reliability Improvement Plan:Phase III and IV Western Region Reliability Improvement Plan (Phases 3 & 4)* • Potentially convert 138 kV Lines 524/824 (Jacinto-Lewis Creek) to 230 kV operation. • Construct a 230 kV transmission line from Cypress to Jacinto. • Construct a 230 kV transmission line from Porter to Lewis Creek. • Install static and dynamic VAR support in the Western Region. * Note: This set of projects may be modified based on further activities and developments occurring at the Louisiana and Texas Commissions.

18. Alternatives to the Western Region Reliability Improvement Plan • Projects identified in Phases 3 and 4 of the WRRIP results in greater reliance on and strengthening of the transmission corridor between the Western Region and the Beaumont area. • Because of recent events such as the isolation of the Western Region from the rest of the Entergy System, the Company has developed several alternatives to the projects described above. These alternatives would strengthen the Western Region’s ties to the west.

19. WRRIP Alternative 1 • Enhancement of the reliability at Grimes Substation in order to reduce the reliance from the Beaumont area • Upgrades of 138 kV Lines 112 and 485 to sufficient capacity • Installation of a 345 kV bulk tie between Grimes and Lewis Creek • This option also requires additional firm local generation.

20. WRRIP Alternative 2 • Enhancement of the reliability of the 345 kV tie to AEP-West in order to reduce reliance from the Beaumont area. • Upgrade of 138 kV Line 485 to sufficient capacity • Installation of a 345 kV switchyard on Line 119 including a 345 kV tie line to Rivtrin Substation • This option also requires additional firm local generation.

21. ALT #2 Construct 345 kV Network Into Rivtrin Enhance 138kV and 345kV Network at Grimes and Lewis Creek Construct/ Enhance 230 kV Network Into Lewis Creek Current Plan: Phases 3 & 4 ALT # 1

22. Approved 2007 ETEC-RelatedTransmission Reliability Projects inEntergy’s Construction Plan

23. Longer-Term Reliability Target Areas (2011+) Potential thermal overloads under single contingency conditions: • 138 kV Line 516 (Sabine – Port Neches) • For the loss of Line 515 (Sabine – Port Neches) • 138 kV overloads in the Jasper-Newton area • For the loss of the Hartburg-Cypress 500 kV line • 138 kV Lines from between Lewis Creek and Dobbin • For the loss of 138kV sources from either the Lewis Creek or Grimes end • [Could be addressed by the Longmire reconfiguration project] • 230 kV Line 496 (China – Sabine) • For the loss of Line 599 (China – Amelia) • 230 kV Line 194 (Hartburg-Helbig) • For the loss of the Hartburg-Cypress 500 kV line • 138 kV Line 88 (Dayton – Cheek) • For the loss of Line 496 (China – Sabine) • 138 kV Line 571 (Jacinto – Porter) • For the loss of Line 822 (China – Porter) • 138 kV Line 150 (Dayton – Long John) • For the loss of Line 579 (Jacinto – Cleveland) • 138 kV Line 561 (Gulfrich – Crown Orange) • For the loss of Line 590 (Gulfrich – Ausimont) • 138 kV Line 582 (Oak Ridge – Porter) • For the loss of Line 886 (Tamina – Porter) • 138 kV Line 86 (Dayton – Eastgate) • For the loss of Line 882 (China – Porter) • 138 kV Line 515 (Sabine – Port Neches) • For the loss of Line 516 (Sabine – Port Neches) • Other target areas/ projects: • Depressed voltages in the Lacon Substation area • WRRIP Phase 4