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Planning Transmission for Uncertainty

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Planning Transmission for Uncertainty WESTERN ELECTRICITY COORDINATING COUNCIL Planning Transmission for Uncertainty: Applications and Lessons for the Western Interconnection FINAL REPORT JANUARY 2016 Jonathan L. Ho, Benjamin F. Hobbs, Pearl Donohoo‐Vallett, Qingyu Xu, Saamrat Kasina, Sang Woo Park, and Yueying Ouyang Department of Geography & Environmental Engineering Environment, Energy, Sustainability & Health Institute The Johns Hopkins University Baltimore, MD Report Prepared for The Western Electricity Coordinating Council Acknowledgement This material is based upon work supported by the Western Electricity Coordinating Council and by the U.S. Department of Energy, Office of Electricity Delivery and Energy Reliability through a contract man‐ aged by the Lawrence Berkeley National Laboratory. The project team would like to thank Vijay Satyal, Gary Simonson, Michael Bailey, and Keenan Moyer of WECC and Joseph Eto of LBNL for their support and advice during this project. We also gratefully acknowledge the contributions of the members of the Technical Advisory Committee whose advice was invaluable in development of the study cases. We also thank Yujia Zhu and Prof. Daniel Tylavsky of the Department of Electrical Engineering at Arizona State University for access to their software for power network reduction and the advice they provided on its use. Jim McCalley contributed to an earlier ver‐ sion of the literature survey in Section 2. However, the authors are solely responsible for any opinions or errors in this document. All authors performed this work when associated with Johns Hopkins University. Jonathan Ho is now with the National Renewable Energy Laboratory, Pearl Donohoo‐Vallett is with Brattle Consultants, and Yueying Ouyang is with Energy & Environmental Economics (E3) Consultants. Disclaimers This report was prepared as an account of work sponsored in part by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agen‐ cy thereof. The information and studies discussed in this report are intended to provide general information to poli‐ cy‐makers and stakeholders but are not a specific plan of action and are not intended to be used in any State electric facility approval or planning processes. Table of Contents List of Figures ............................................................................................................................................... iv List of Tables ............................................................................................................................................... vii Executive Summary ....................................................................................................................................... 1 ES‐1. Overview ......................................................................................................................................... 1 ES‐2. Motivation and Goal ....................................................................................................................... 1 ES‐3. Model Structure .............................................................................................................................. 2 ES‐3. Scenarios Considered ...................................................................................................................... 6 ES‐4. Quantifying the Value of Stochastic Programming ......................................................................... 8 ES‐5. Quantifying the Value of Stochastic Programming ......................................................................... 9 ES‐6. Sensitivity of Transmission Recommendations to Assumptions .................................................. 12 ES‐6. Conclusions ................................................................................................................................... 14 1 Introduction ........................................................................................................................................ 15 1.1 Motivation ................................................................................................................................... 15 1.2 Scope ........................................................................................................................................... 17 2 A Brief Review of Economic Methods for Long‐Run Transmission Planning ...................................... 20 2.1 Methods Used in Practice and Their Limitations ........................................................................ 20 2.2 What is Stochastic Transmission Planning? ................................................................................ 21 3 Methodology ....................................................................................................................................... 26 3.1 JHSMINE Transmission Planning Tool ......................................................................................... 26 3.2 Specific WECC Implementations of JHSMINE ............................................................................. 28 3.3 Experimental design .................................................................................................................... 29 4 Data Development .............................................................................................................................. 32 4.1 Scenario Definitions and Probabilities ........................................................................................ 32 4.1.1 Scenario definition and development ................................................................................. 32 4.1.2 Probability definition .......................................................................................................... 36 4.2 WECC 21‐Zone Network Definition ............................................................................................. 40 4.3 WECC 300 Bus Network Definition by Network Reduction ........................................................ 43 4.3.1 Preserved Bus Selection ...................................................................................................... 44 4.3.2 Generation Assumptions for the 300‐Bus Network ............................................................ 48 ii 4.4 Load Assumptions and Aggregation ........................................................................................... 49 4.5 Investable Transmission Lines ..................................................................................................... 50 4.6 Hydro scenario development for 21‐zone model ....................................................................... 52 4.7 Generation Data Geographical Aggregation ............................................................................... 54 4.7.1 Existing Generator Properties (Sources: Common Case, Transmission Expansion Planning Dataset) ............................................................................................................................................. 54 4.7.2 Regulation Rules (Sources: DSIRE, Common Case) ............................................................. 55 4.7.3 Investable Generation Location (Sources: Transmission Expansion Planning Dataset, WREZ report) ............................................................................................................................................. 57 5 Results and Discussion ........................................................................................................................ 59 5.1 Is it Practical to Use Stochastic Programming in WECC? ............................................................ 59 5.2 Do Stochastic Transmission Plans differ from Deterministic Plans? ........................................... 61 5.2.1 Differences between the Stochastic Plans and the Deterministic Plans ............................ 61 5.2.2 But are Stochastic Plans Actually Better? ........................................................................... 64 5.2.3 Robust Planning: Can Good Plans be Defined by Identifying Lines Chosen by Multiple Deterministic Models? ........................................................................................................................ 69 5.3 Sensitivities to Model Structure, Uncertainties, and Assumptions ............................................ 71 5.3.1 Are Stochastic Solutions Sensitive to the Number or the Probabilities of the Scenarios ... 71 5.3.2 Failure to Launch: How Does Uncertainty in CCTA Line Completion Affect Transmission Plans? ............................................................................................................................................. 74 5.3.3 Does Representation of Generator Flexibility affect Transmission Plans? ......................... 80 5.3.4 How Does Network
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