2017 System Assessment Jonathan Young February 2017

Outline Timeline Active Timeline Work Base Cases Contingency & RAS Files What should we study? Special / Sensitivity Studies

Timeline Provide Review Cases for Members Finalize Ten Year Plan Solicit Order 1000 Potential Needs suggestions December Early January Review and Finalize Study Cases/Dynamics Data(Due by 16th) Mid January (After Case Finalization) Provide TPL /Stability Contingency & Automatic Action Files January Develop Contingency Lists Reaffirm base and sensitivity study plan Request updates to 2022 cases to create 2023 cases February Process & Review Contingency Results Evaluate Order 1000 Potential Needs Process & Review Transient Stability Study Contingency Results March/April Prepare System Assessment Identify Order 1000 Needs Prepare Need Statement Approve System Assessment Recommend Study Teams for Proposed & Order 1000 Needs TBD Timeline

Active Timeline Work Distribute Additional Updates (unplanned) Provide TPL /Stability Contingency & Automatic Action Files Develop Contingency Lists Reaffirm Base and Sensitivity Study Plan Request Updates to 2022 Cases to Create 2023 Cases

WECC Cases For Study Plan Base Case Desired Study Year WECC Build Yr Notes 1-2 Year Heavy Summer 2017 HS2-OP 2017 + 2 = 2019 2016 1-2 Year Heavy Winter 2016-17 HW3-OP 2017 + 2 = 2018/19 5 Year Heavy Summer 2022 HS1 2017 + 5= 2022 Plan to create a 2023 Case in early 2017 5 Year Heavy Winter 2021-22 HW2 2017 + 5= 2021/22 Long Term Heavy Summer 2026 HS1 2017 + 10= 2027 2015 Long Term Heavy Winter 22025-26 HW1 2017 + 10= 2026/27 1-5 Year Light 2017 7 LS 2019

Contingency & RAS Models Contingency Lists: All Cases: Base: Models to produce P1-P7 Addition: Models to accommodate any sensitivities RAS: TBD Recommendation: At a minimum, developing a way to indicate if a RAS could operate for the outage condition.

Confirmation on What to study? Traditionally we have studied all seven cases produced in the System Assessment process. It has been suggested that we still produce the cases but focus more on sensitivities and assessment fewer cases. We are recommending assessing the long-term peak cases and an off peak case. Comments?

Special / Sensitivities Studies N-1-1: Refine study method from past year’s to better meet the member needs High Renewable Study: Expand on mapping method used from 2016 Biennial Plan Evaluate the need for the delayed 2016 Operational & Planning gap study and study if needed Special Studies Geomagnetic Disturbance Study to align with NERC standard MOD-33

Questions?