http://nodal.ercot.com 1

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Texas NodalCRR Conceptual System DesignCRR Team
Presentation to TPTFBeth Garza, CRR Deployment
ManagerNovember 6, 2006
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Approval Process

• Today
• 11/6 TPTF Presentation
• Next Steps
• 11/13 Comments Due
• 11/22 CRR Team Addresses Comments and Distributes
• 11/28 TPTF Presentation of Comment Disposition

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Conceptual System Design (CSD) Outline

• The CRR System five subsystems
• Market User Interface (MUI)
• Market Operator Interface (MOI)
• Data Interface
• Database
• Calculation
• For each subsystem we will describe
• Traceability
• Inputs/Outputs
• Processing
• System Overview / Technical Architecture
• Supplementary Specifications
• Appendix Mapping to Enterprise Level Use Case

Data Interface
MUI
DB
MOI
Calculation
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CRR System Black Box Diagram
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Market User Interface Key Points Issues

• Mapping of CRR data to areas of the MIS portal
  (Public, Secure, Certified)
• Common Data common to everybody (not just CRR
  Account Holders)
• Private Data only available to a specific CRR
  Account Holder
• Information related to CRRs on the MIS Secure
  area will NOT require users to be identified as
  CRR Account Holders
• CRR System assumes no Programmatic Interface for
  bids and offers
• Considered change in scope
• Current solution of file upload is sufficient to
  meet needs of project
• Counter-Party/CRR Account Holder Mapping
• Each CRR Account Holder will represent a single
  Counter-Party (legal entity)
• Each Counter-Party will only have a single
  Account Holder
• CRR System is capable of supporting a one-to-many
  (one Counter-Party to many Account Holders)

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Data Interface Data Input Table
INPUT
OUTPUT
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Data Interface Data Output Table
INPUT
OUTPUT
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Calculation Key Points Issues

• Early reviews identified opportunities for
  additional clarification
• Network Constraint
• Budget Constraint

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Next Steps

• Next Steps
• 11/13 Comments Due from TPTF
• 11/22 CRR Team Addresses Comments and Distributes
• 11/28 TPTF Presentation of Comment Disposition