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Entergy Gulf States, Inc.(Texas)

Approved & Proposed Transmission Reliability

Projects

Entergy/ETEC Subcommittee Meeting

The Woodlands, TX

November 28, 2006

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Recap of 2004-06 EGSI-TX TransmissionWestern Region Reliability Improvement Plan:

Phase IIScenario:• 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.

o Loss of Lewis Creek Unit & 345 kV Line 119 (Crockett-Grimes)o Loss of Lewis Creek Unit & 230 kV Line 568 (China-Jacinto)o 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:o 500/230 kV Auto (Cypress) COMPLETEDo Construct Line 822 (China-Porter) 230 kV COMPLETEDo Construct 230/138 kV Porter Substation COMPLETEDo Upgrade Line 599 (Amelia-China) 230 kV COMPLETEDo Install 300 MVAr SVC at Porter Substation COMPLETEDo Install series compensation on Line 822 (China-Porter) COMPLETED

Estimated Cost: $115 MM

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2006 EGSI-TX Approved Transmission Reliability Projects

Western Region Phase II

INSTALLED 300 MVAr

SVC

INSTALLED 300 MVAr

SVC

INSTALLED SERIES

CAPACITOR ON LINE 822

INSTALLED SERIES

CAPACITOR ON LINE 822

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Approved 2007 EGSI-TXTransmission Reliability Projects in

Entergy’s Construction Plan

Project Name

In Service

Year

Estimated Cost

($MM) Comments

Grimes: Reconfigure Substation 2007 $0.5 Approved

Kolbs & Hanks: 230 kV Bus Upgrades 2007 $0.2 Approved

Splendora Switch Clearance/Replacement (Mandatory – Safety) 2007 $0.08 Approved

EGSI-TX Underrated Breaker Upgrades (12- 69 kV breakers, Mandatory – Safety) 2007 - 2008 $1.3 Approved

Calvert: Expand cap bank to 12 MVAr 2008 $0.6 Approved

Sandy Shores: Install 11 MVAr cap bank 2008 $0.5 Scoping Only

Porter-Tamina-Conroe Upgrade 138 kV lines 2008 $5.5 Approved

Beaumont 69 kV Improvement Plan 2009 $8 Approved

Western Region Reliability Improvement Plan: Phase 3 2010 $2

Scoping & Engineering Only

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Approved EGSI-TX Transmission Reliability Projects in Entergy’s Construction Plan

Sandy Shores:Add 69 kV Cap Bank

Calvert: Expand 69 kV Cap Bank

Helbig

Calvert

Sandy Shores

Grimes: Reconfigure 345/138 kV Substation

Grimes

South Beaumont

Amelia

Beaumont 69 kV System Improvement Plan

Conroe

Tamina

Porter-Tamina-Conroe:Upgrade 138kV Lines

Porter

Others:• WRRIP- Phase 3

Scoping & Engineering

• Upgrades of underrated breakers (various locations, mandatory-safety)

• Splendora: Replace switch (mandatory-safety)

Kolbs

HanksKolbs & Hanks:

Upgrade 230 kV Bus

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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)

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Grimes 345/138 kV Substation Reconfiguration

AUTO #1

AUTO #2 FRO

NTIE

RC

RO

CK

ETT

RECONFIGURE 345 kV BUS

RECONFIGURE 345 kV BUS

INSTALL 138 kV BREAKER

INSTALL 138 kV BREAKER

INSTALL 345 kV BREAKER

INSTALL 345 kV BREAKER

2007

345kV

138kV

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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

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HanksKolbs

Hanks & Kolbs: Upgrade Substation Bus

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EGSI-TX Circuit Breaker UpgradesScenario:• 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

o Cow 69kV #5515, #5510o Orange 69kV #3165, 3145

– 2007o Orange 69kV #3365o South Beaumont 69kV #3700o Port Neches 138kV #3345o West End 69kV #22135

– 2008o Orange 69kV #3370o Dupont Bulk 69kV #3255, #3260o Helbig 69kV #5585

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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

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EGSI-TX 69 kV Voltage Support

INSTALL 11MVAR

CAP BANK

INSTALL 11MVAR

CAP BANK

EXPAND EXISTING CAP BANK

EXPAND EXISTING CAP BANK

2007

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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

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2007

UPGRADE TO 531MVA CAPACITY

UPGRADE TO 531MVA CAPACITY

Porter-Tamina-Conroe:Upgrade 138 kV Lines 823 & 886

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69 kV Beaumont Network Upgrades

Scenario:• In the 69 kV Beaumont area there exists several single contingency

thermal overloads including:o 69 kV Line 581 (Helbig – Rosedale)o 69 kV Line 468 (Elizabeth – Gallier)o 230/69 kV Helbig Autotransformerso 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.o Approximately 5.5 miles of 69 kV transmission lines

Estimated Cost: $8 MM

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69 kV Beaumont Network Upgrades

CARDINAL

LAMAR

SOUTH BEAUMONTBULK

VIRGINIALINCOLN

YANKEEDOODLE

CROCKETT

DUPONT BEAUMONT

NITROCDT

L-458

L-458

L-1

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UPGRADE LINE 576

UPGRADE LINE 576

UPGRADE LINE 190

UPGRADE LINE 190

UPGRADE LINE 98

UPGRADE LINE 98

CLOSE N.O.

SWITCH

CLOSE N.O.

SWITCH

CLOSE N.O.

BREAKER

CLOSE N.O.

BREAKER

ADD LINE BREAKERS

ADD LINE BREAKERS

2007

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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.

2010+

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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.

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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.

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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.

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Current Plan: Phases 3 & 4

ALT #2

ALT # 1

Construct/ Enhance 230 kV Network Into Lewis

Creek

Construct/ Enhance 230 kV Network Into Lewis

Creek

Construct 345 kV Network Into Rivtrin

Construct 345 kV Network Into Rivtrin

Enhance 138kV and

345kV Network at Grimes and Lewis Creek

Enhance 138kV and

345kV Network at Grimes and Lewis Creek

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Project NameIn Service

Year

Estimated Cost ($MM)

Comments

JNEC Deweyville - Add breakers & cut-in Line 2007 $0.4 Approved

SHECO - Menard Substation Upgrades 2007 $0.1 Approved

SHECO - Turkey Creek Substation Upgrades 2007 $0.1 Approved

Approved 2007 ETEC-RelatedTransmission Reliability Projects in

Entergy’s Construction Plan

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Longer-Term Reliability Target Areas (2011+)

• 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)

• 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]

Potential thermal overloads under single contingency conditions:

• Other target areas/ projects:– Depressed voltages in the

Lacon Substation area– WRRIP Phase 4