WEST TEXAS TRANSMISSION PLANNING Workshop for Public Utility Commission Project No. 25819 07242002

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WEST TEXAS TRANSMISSION PLANNINGWorkshop for
Public Utility CommissionProject No. 25819
07/24/2002

• KENNETH A. DONOHOO, P.E.
• Manager of System Planning, Technical Operations
• kdonohoo_at_ercot.com
• www.ercot.com

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TRANSMISSION SYSTEM

• Is a Network
• Not a one way system
• Flows change with changing system conditions
• Events on the network can have far reaching
  effects across the whole system
• All customers share the benefits of a reliable
  interconnected network
• Is constantly changing and is very rapid
• Generation Output Changes
• Transmission System Changes

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MAJOR CONCERNS

• HOW MUCH PEAK CAPACITY SHOULD ERCOT BUILD
  TRANSMISSION FOR?
• Seasonal Production
• Diversity
• Time of Day
• Generation Interconnect Agreements
• STABILITY AFFECTS
• As the Wind Blows
• Regulation Ancillary Services
• Accurate Appropriate Aggregated Models Needed
• VOLTAGE CONTROL
• As the Wind Blows
• May Be Critical for Keeping Renewable Online
• High Voltage Off Peak a Major Concern
• STATCOM/DVAR/Mini SVC Devices
• Accurate Appropriate Aggregated Models Needed

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WEST TEXAS CURRENT

• TRANSMISSION TRANSFER LIMIT
• 1,100 MW to 1,300 MW
• Stability Thermal Limits
• EXISTING GENERATION
• 5,000 MW
• Growing Everyday
• LOAD
• 3,300 MW
• 1.0 to 1.5 Per Year Growth
• EXPORTABLE GENERATION
• 1,700 MW
• Higher Under Light Load Conditions

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WEST TEXAS POSSIBLE FUTURE

• GENERATION
• 7,000 MW to 8,500 MW
• LOAD
• 3,300 MW
• EXPORTABLE GENERATION
• 3,700 MW to 5,200 MW
• 100 to 200 INCREASE
• TRANSFER LIMIT 1,800 MW to 2,300 MW
• Stability Thermal Limits
• Voltage Limits

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WEST TEXAS TRANSFER STUDY
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Alternative A

• 345 kV Morgan Creek San Angelo Comanche SW
  Comanche Peak circuit
• 345 kV Jacksboro West Denton circuit
• 24 other transmission upgrades
• 1,827 Mvar of capacitor banks
• 270M cost index

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Alternative B

• 345 kV San Angelo Killeen circuit
• 345 kV Jacksboro West Denton circuit
• 18 other transmission upgrades
• 1,838 Mvar of capacitor banks
• 337M cost index

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Alternative C

• 345 kV Morgan Creek Parker circuit
• 345 kV Jacksboro West Denton circuit
• 18 other transmission upgrades
• 1,226 Mvar of capacitor banks
• 356M cost index

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Alternative D

• 765 kV Morgan Creek West Denton circuit
• 345 kV West Denton NW Carrollton circuit
• 345 kV West Denton Anna circuit
• 11 other transmission upgrades
• 978 Mvar of capacitor banks
• 480M cost index

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Alternative E

• DC Line Odessa West Denton circuit
• 345 kV West Denton NW Carrollton circuit
• 345 kV West Denton Anna circuit

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Preliminary Results

• Studies have been performed for options A C and
  both alternatives indicated to be unstable (not
  acceptable)
• Both cases are unstable in steady state without
  static VAR devices located at wind generation
  sites
• Suspect options B D will also be unstable
• VAR devices may be critical to keeping system
  stable and wind generation on line
• Propose change in Reactive Standards for Wind
  Generation
• Dynamic modeling of the wind farms and the
  combined cycle plants are problematic in
  completing this work

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MODEL DEVELOPMENT

• Development and Validation ERCOT Wind Generation
  Models
• Contract Complete and Executed 07/22/2002
• Electrotek Concepts, Inc.
• ERCOT System Planning Staff is Leading the
  Project
• Provides significant support to Wind Generation
  projects
• Includes monitoring of four sites

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PROJECT TIMELINE
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QUESTIONS