The California ISO 2023-2024 transmission planning cycle involves key stakeholder activities from 2023 through early 2024. Each year, the ISO conducts its transmission planning process to identify potential system limitations as well as opportunities for system reinforcements that improve reliability and efficiency. The transmission planning process core product is the ISO Transmission Plan, which provides an evaluation of the ISO control grid, examines conventional grid reliability requirements and projects, summarizes key collaborative activities and provides details on key study areas and associated findings.
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Jun 03, 2024 Board approved transmission plan posted
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May 23, 2024 Board of Governors approval
Jul 18, 2024 Board of Governors approval for transmission plan extension |
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https://stakeholdercenter.caiso.com/InitiativeDocuments/New-Humboldt-Fern-Road-500kV-Transmission-Line-Project-Reconciled-Final-Costs.pdf
New Humboldt Fern Road 500kV Transmission Line Project Reconciled Final Costs 08/15/2025
New Humboldt Collinsville 500kV Substation and Transmission Line Project Reconciled Final Costs 08/15/2025
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https://stakeholdercenter.caiso.com/InitiativeDocuments/New-Humboldt-Collinsville-500-kV-Line-And-Substation-project-Project-Sponsor-Selection-Report.pdf
https://stakeholdercenter.caiso.com/InitiativeDocuments/New-Humboldt-Fern-Road-500kV-Line-Approved-Project-Sponsor-Selection-Report.pdf
New Humboldt to Fern Road 500 kV Line Project - Project Sponsor Selection Report 06/02/2025
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Qualified project sponsor applications https://stakeholdercenter.caiso.com/InitiativeDocuments/List-of-Qualified-Applicants-Humboldt-to-Fern-Road-500kV-Transmission-Line-Project.docx
List of Qualified Applicants - Humboldt to Fern Road 500 kV Transmission Line Project 02/11/2025
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Validated Project Sponsor Applications https://stakeholdercenter.caiso.com/InitiativeDocuments/ListofValidatedProjectSponsorApplications-HumboldtCollinsville500KVSubstationandTransmissionLineProject.pdf https://stakeholdercenter.caiso.com/InitiativeDocuments/List-of-Validated-Project-Sponsor-Applications-New-Humboldt-to-Fern-Road-500-kV-Transmission-Line-Project.pdf |
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https://stakeholdercenter.caiso.com/InitiativeDocuments/2023-2024-Competitive-Solicitation-Questions-Matrix-R3.pdf
2023-2024 Competitive Solicitation Questions Matrix R3 09/23/2024
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https://stakeholdercenter.caiso.com/InitiativeDocuments/2023-2024-Competitive-Solicitation-Questions-Matrix-R2.pdf
2023-2024 Competitive Solicitation Questions Matrix R2 08/27/2024
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https://stakeholdercenter.caiso.com/InitiativeDocuments/2023-2024-Competitive-Solicitation-Questions-Matrix-R1.pdf
2023-2024 Competitive Solicitation Questions Matrix R1 08/12/2024
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https://stakeholdercenter.caiso.com/InitiativeDocuments/2023-2024-Competitive-Solicitation-Questions-Matrix-R0.pdf
2023-2024 Competitive Solicitation Questions Matrix R0 07/30/2024
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/2023–2024-Transmission-Planning-Process-Phase-3-Competitive-Solicitation-jun-26-2024.pdf
2023-2024 Transmission Planning Process Phase - 3 - Competitive Solicitation - Jun 26, 2024 06/24/2024
2023-2024 Transmission Planning Process Phase - 3 Sequence Revised Schedule 10/03/2024
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/ISO-Responses-Stakeholder-Comments-2024-June-17.pdf
ISO Responses - Stakeholder Comments - Jun 17, 2024 07/16/2024
Draft - Addendum1- 2023-2024 Transmission Plan 07/16/2024
Presentation - 2023-2024 Transmission Planning Process - June 17, 2024 06/13/2024
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https://stakeholdercenter.caiso.com/InitiativeDocuments/Key-Selection-Factors-2023-2024-Transmission-Planning-Process.pdf
Key Selection Factors - 2023-2024 Transmission Planning Process 06/12/2024
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https://stakeholdercenter.caiso.com/InitiativeDocuments/BOARDAPPROVED_2023-2024_TransmissionPlan.pdf
Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix A - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix B - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix C - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix D - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix E - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix F - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix G - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix H - Board Approved 2023-2024 Transmission Plan 06/03/2024
Appendix I - Board Approved 2023-2024 Transmission Plan 06/03/2024
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https://stakeholdercenter.caiso.com/InitiativeDocuments/REVISEDDRAFT_2023-2024_TransmissionPlan.pdf
Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix A - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix B - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix C - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix D - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix E - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix F - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix G - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix H - Revised Draft 2023-2024 Transmission Plan 05/15/2024
Appendix I - Revised Draft 2023-2024 Transmission Plan 05/15/2024
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/ISO-Responses-Stakeholder-Comments-2024-Apr-9.pdf
ISO Responses - Stakeholder Comments - Apr 09, 2024 04/16/2025
Presentation - 2023-2024 Transmission Planning Process - Apr 09, 2024 04/05/2024
Draft 2023-2024 Transmission Plan 04/01/2024
Appendix A - Draft 2023-2024 Transmission Plan 04/01/2024
Appendix B - Draft 2023-2024 Transmission Plan 04/01/2024
Appendix C - Draft 2023-2024 TransmissionPlan 04/01/2024
Appendix D - Draft 2023-2024 TransmissionPlan 04/01/2024
Appendix E - Draft 2023-2024 TransmissionPlan 04/01/2024
Appendix F - Draft 2023-2024 TransmissionPlan 04/01/2024
Appendix G - Draft 2023-2024 Transmission Plan 04/01/2024
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Letter |
https://stakeholdercenter.caiso.com/InitiativeDocuments/Letter-Project-Cost-Update-for-GLW-VEA-Area-Upgrades-and-Beatty-230-kV-Projects-Nov142023.pdf
Letter - Project Cost Update for GLW-VEA Area Upgrades and Beatty 230 kV Projects - Nov 14, 2023 01/02/2024
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/Presentation-2023-2024-Transmission-Planning-Process-Nov16223.pdf
Presentation - 2023-2024 Transmission Planning Process - Nov 16, 2023 11/14/2023
ISO Responses to Comments - 2023-2024 Transmission Planning Process - Nov 16, 2023 04/09/2024
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/ISOResponsestoComments-2023-2024TransmissionPlanningProcess-Sep26-27-2023.pdf
ISO Responses to Comments - 2023-2024 Transmission Planning Process - Sep 26-27, 2023 11/27/2023
CAISO Presentation - 2023-2024 Transmission Planning Process - Sep 27, 2023 09/22/2023
GLW Presentation - 2023-2024 Transmission Planning Process - Sep 27, 2023 09/22/2023
PG&E Presentation - 2023-2024 Transmission Planning Process - Sep 27, 2023 09/22/2023
SCE Presentation - 2023-2024 Transmission Planning Process - Sep 27, 2023 09/26/2023
SDGE Presentation - 2023-2024 Transmission Planning Process - Sep 27, 2023 09/22/2023
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/Agenda-2023-2024TransmissionPlanningProcess-Sep26-27-2023.pdf
Agenda - 2023-2024 Transmission Planning Process - Sep 26-27, 2023 09/22/2023
CAISO Presentation - 2023-2024 Transmission Planning Process - Sep 26, 2023 09/22/2023
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Phase 2 - conduct technical studies and develop comprehensive plan |
The ISO performs technical studies, and with stakeholders develops an annual comprehensive transmission plan that examines the ISO controlled grid and reliability requirements and identifies mitigation solutions. Transmission mitigation solutions may meet reliability, economic or public policy-driven needs that support state, federal, municipal and county policy requirements and directives.The ISO performs technical studies, and with stakeholders develops an annual comprehensive transmission plan that examines the ISO controlled grid and reliability requirements and identifies mitigation solutions. Transmission mitigation solutions may meet reliability, economic or public policy-driven needs that support state, federal, municipal and county policy requirements and directives. |
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Reliability assessment https://www.caiso.com/PublishedDocuments/2023-2024-Preliminary-Reliability-Assessment-Results.zip
Link to 2023-2024 Preliminary Reliability Assessment Results.zip 12/20/2023
2023-2024 Preliminary Reliability Assessment Results 08/18/2023
2023-2024 Final Reliability Results 10/31/2023
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https://stakeholdercenter.caiso.com/InitiativeDocuments/Final-Study-Plan-2023-2024-Transmission-Planning-Process.pdf
Final Study Plan - 2023-2024 Transmission Planning Process 08/16/2023
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Phase 1 - develop study plan |
In collaboration with stakeholders, the ISO develops and finalizes a study plan that consists of a common set of assumptions for reliability and other planning studies the ISO will perform in Phase 2. The development of a conceptual statewide transmission plan begins in this phase and may be completed during Phase 1 or Phase 2. Stakeholders may also request economic planning studies to assess potential economic benefits (such as congestion relief) in specific areas of the grid. |
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/ISOResponsestoComments–2023-2024TransmissionPlanningProcess-Eldorado230kVShortCircuitDutyMitigationProject–Jun282023.pdf
https://stakeholdercenter.caiso.com/InitiativeDocuments/Presentation-2023-2024-Transmission-Planning-Process-Jun282023.pdf
Presentation - 2023-2024 Transmission Planning Process - Jun 28, 2023 06/27/2023
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Web meeting |
https://stakeholdercenter.caiso.com/InitiativeDocuments/ISOResponsestoComments–2023-2024TransmissionPlanningProcess–Feb282023.pdf
ISO Responses to Comments – 2023-2024 Transmission Planning Process – Feb 28, 2023 11/20/2023
Draft Study Plan - 2023-2024 Transmission Planning Process - Feb 28, 2023 02/23/2023
Presentation - 2023-2024 Transmission Planning Process - Feb, 28, 2023 02/27/2023
Agenda - 2023-2024 Transmission Planning Process - Feb, 28, 2023 02/27/2023
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