ICT Strategic Transmission Plan (ISTEP)Review and Status UpdateEntergy Transmission Summit July 29, 2008 Astor Crown Plaza New Orleans, LouisianaDouglas Bowman, PELead Engineer, ICT Planning501-688-1640dbowman@SPP.org

ISTEP

ICT Strategic Transmission Expansion PlanAttachment KParagraph 14.1 - The ICT will identify potential economic upgrades on the Transmission System, including upgrades to existing facilities as well as construction of new facilities.Paragraph 14.3 The ICT will identify such upgrades based on screening criteria, which may include considerations such as frequent transmission loading relief events, frequently constrained flowgates in the Available Flowgate Capability process or Weekly Procurement Process (WPP), flowgates with high congestion costs as identified in the WPP process, and commonly invoked must-run operating guides.

ISTEP Scope and PurposePromote transmission expansion on the Entergy transmission system by identifying and developing economic projects that address transmission constraints through powerflow studies and stakeholder inputFocus on creating new, higher-voltage transmission in order to address potential issues on the Entergy transmission system, as opposed to upgrading the underlying lower-voltage system.Not used for cost allocationEntergy is not obligated to construct ISTEP projectsNot related to reliability requirements

ISTEP ObjectiveImprove Load-Serving CapabilityImprove Inter-regional Transfer CapabilityImprove Load Pockets/Load CentersRelieve Constraining Flowgates

ISTEP Phase ICompleted 12/2007Identified Operational Limitations213 TLRs resulting in curtailment of 340GWh of firm and non-firm transmission service from January to October, 2007.Identified Transfer Capability LimitationsMost limiting flowgates identified

ISTEP Phase I (continued) Modeling2015 Summer Peak CaseIncludes 2008 Construction Plan upgradesDoes not include Base Plan upgradesDoes not include Operating guides, redispatch, breaker operation, or other mitigation plans

ISTEP Phase I (continued)20 proposed projects consisting of one or more transmission upgradesProposed ProjectsLouisiana 7 ProjectsArkansas 5 ProjectsMississippi 5 ProjectsTexas 1 ProjectOther 2 Short Term Projects

ISTEP Phase IIStakeholders ranked Phase I projectsApproximately 20 stakeholder responsesTop 5 were selected from each stakeholder rankingFinal ranking was developed using a combination of stakeholder rankings and the ICTs knowledge of the Entergy system.

ISTEP Phase II ProjectsSouth LA BulkCentral Arkansas 230 kVAcadiana AreaCentral MS BulkMcAdams Series ReactorSeams Projects

South LA BulkProjects address: WOTAB Import Constraining flowgates Acadiana Flowgates: Webre Wells Mt. Olive Hartburg Wilbert Livonia Terrebonne Greenwood Cecelia Moril Meaux - JudiceSouth LA & Acadiana Fancy Point Hartburg 500 kVWebre Richard 500kV

Central AR 230kVProjects address: Constraining flowgates Flowgates: Morrilton East-GleasonConway- Donaghey Cabot-Gold Creek 230kVGleason - Conway W. 230 kVGold Creek-Conway Industrial 230kVCentral AR 230kV Conway W. Conway Ind. 230kV

Central AR 230kVProjects address: Constraining flowgates Flowgates: Morrilton East-GleasonConway- Donaghey Kanis-Mabelvale 230 kV Wrightsville-Little Rock South 230kVKanis 230/115kV transformerLittle Rock South 230/115kV transformerWrightsville 500/ 230kV transformerMabelvale 500/230kV transformer Central AR 230kV

Projects address: Constraining flowgates Flowgates: Morrilton East-GleasonConway- Donaghey Mt. Pine South-Carpenter 230 kV Carpenter-Hot Springs EHV 230kVHot Springs-Cheetah 230kVMabelvale-Cheetah 230kVCheetah-Mt. Pine South 230kVHot Springs EHV 500/230kV transformer Central AR 230kV

Acadiana AreaProjects address: WOTAB Import Constraining flowgates Acadiana Flowgates: Webre Wells Mt. Olive Hartburg Wilbert Livonia Terrebonne Greenwood Cecelia Moril Meaux - JudiceSouth LA & Acadiana Richard Sellers 230 kV

Sellers Meaux 230 kV

Sellers Segura 230 kV

Sellers Labbe 230kVLabbe Bonin 230 kVWells Labbe 230kV

Central MS BulkProjects address: Constraining flowgates Flowgates: Ray Braswell Baxter WilsonCentral MS Bulk Grand Gulf Ray Braswell 500 kV

McAdams Series ReactorInstall a 36 reactor in series with McAdams 500/230 kV transformerMcAdams Series Reactor 500/230kV

Seams ProjectsFt. Smith-ANO-ISES 500kVEl Dorado Longwood Series CompensationMessick 500/230Ft. Smith-NW Texarkana-McNeil 500kV-TurkS. Fayetteville Van Buren ANO 500kV

Ft. Smith ANO ISES 765 kVFt. Smith ANO ISES 500 kVProjects address:Improve SPP/Entergy Interface

El Dorado Longwood Series Compensation

Increase Transfer Capability of the LineEl Dorado Longwood Series Compensation

Messick 500/230 kV Mt Olive Hartburg Tap Stability IssueImprove SPP/Entergy InterfaceExisting Mt. Olive - Hartburg 500kVMessick 500/230kV

Ft. Smith NW Texarkana Turk McNeil 500 kVFT. Smith NW Texarkana 500kVNW Texarkana Turk 500kVTurk McNeil 500kVTurkProjects address:Improve SPP/Entergy Interface

S. Fayetteville Van Buren ANO 500kVS. Fayetteville Van Buren 500 kVVan Buren ANO 500kVProjects address: Improve SPP/Entergy Interface

StatusSouth LA BulkEngineering analysis completeEconomic analysis proceedingCentral Arkansas 230 kVEngineering analysis underwayAcadiana AreaEngineering analysis completeCurrently in stakeholder negotiations

Status (continued)Central MS BulkEngineering analysis underwayMcAdams Series ReactorEngineering analysis completeCurrently in stakeholder negotiationsSeams ProjectsEngineering analysis underway

ISTEP TimelineStakeholder comment period

Next StepsICT to study ISTEP projects in further detailContinue engineering analysis of ISTEP and seams projectsComplete Webre-Wells economic analysis Complete economic analysis of remaining ISTEP and seams projects