Reliability Assessment Committee Reliability Workshop Priorities Dave Angell, RAC Chair Western Electricity Coordinating Council

Western Electricity Coordinating Council Approach Priority Topic Details Potential Action Zen approach Knowing the question is the first step to knowing the answer. Western Electricity Coordinating Council

Near-Term Priorities -> RAC Improve inverter-based resources modeling in WECC base cases Evaluate changing resource mix impacts Clarify the roles, responsibilities and relationships between WECC Regional Planning Groups Transmission Planners Other stakeholders The answers from the Reliability Workshop are the near-term priorities Western Electricity Coordinating Council

Renewable Energy Models WECC Approved Dynamic Model Library Version January 2018 GE PSLF Status Comments reec_a approved 3/19/14 Renewable energy electrical control model for Wind type 3/4 and Photovoltaic reec_b Renewable energy electrical control model for Photovoltaic WECC Approved Dynamic Model Library From EPRI Model User Guide - The collaborative community of stakeholders has worked under the Western Electricity Coordinating Council’s (WECC) Renewable Energy Modeling Task Force (REMTF). Thus, at the culmination of the work, the models were WECC approved and have found their way into several of the major commercial software platforms, namely, Siemens PTI PSS®E, GE PSLFTM, PowerWorld Simulator and PowerTech Labs simulations tools Western Electricity Coordinating Council

Western Electricity Coordinating Council Blue Cut Fire Event Western Electricity Coordinating Council

Western Electricity Coordinating Council Canyon 2 Fire Event Western Electricity Coordinating Council

Western Electricity Coordinating Council reec_a Complex Western Electricity Coordinating Council

Western Electricity Coordinating Council reec_b Simpler Western Electricity Coordinating Council

Action Update WECC Approved Dynamic Model Library GE PSLF Status Comments reec_a approved 3/19/14 Renewable energy electrical control model for Wind type 3/4 and Photovoltaic reec_b Renewable energy electrical control model for Photovoltaic Where different variants of the same model exist, the preferred version for submittal to WECC is highlighted in green. Western Electricity Coordinating Council

Changing Resource Mix Impacts Existing transmission path ratings Remedial Action Scheme effectiveness/fault-duty Resource adequacy and the effectiveness of traditional methods for determining resource adequacy The transmission and distribution system interface due to DER Essential Reliability Services specific to the Western Interconnection Western Electricity Coordinating Council

Transmission Path Ratings Western Electricity Coordinating Council

Western Electricity Coordinating Council Flow Limited Paths Transmission Paths may be limited by the amount of available resources rather than reliability considerations Studies and analyses performed to determine the Accepted Rating of a transfer path must use realistic simulations A transmission Path's Accepted Rating will not be lowered because its maximum achievable flow is reduced due to system changes made by others System owners that make such changes shall be responsible for mitigating any adverse impacts on the other system(s) Western Electricity Coordinating Council

Remedial Action Scheme Effectiveness Colstrip Remedial Action Scheme (RAS) Acceleration Trend Relay (ATR) The generators advance during a short circuit on the power system. The ATR measures how fast the generators are advancing and trips unit(s) if to remain stable. When these units are replaced with wind, the ATR will not be available and a new RAS will need to be developed. Western Electricity Coordinating Council

Path Ratings & RAS - Action Under Review and Revision Western Electricity Coordinating Council

Determining Resource Adequacy 13.5% 14% 39% 27% Information from the WECC 2017 Reliability Report – 2016 data Total Capacity 267,000 MW Assess vulnerabilities from fuel availability Need ability to analyze more resource variability Western Electricity Coordinating Council

Resource Adequacy – Light Load System Peak July 27th at 5:00 PM System Minimum May 8th at 5:00 AM Western Electricity Coordinating Council

Light Load in California Cal Independent System Operator Western Electricity Coordinating Council

Resource Adequacy – Load Variability California Energy Commission data from November 2017 Western Electricity Coordinating Council

Resource Adequacy - Action Expand resource adequacy measures probabilistic approaches that reflect resource and load variability and reliability characteristics Include non-peak system conditions Western Electricity Coordinating Council

DER and the T & D Interface Distributed Energy Resources energy contribution in 2017 by state Western Electricity Coordinating Council

DER and the T & D Interface - Action Ensure there is sufficient detail on DER capability and performance to determine BPS impact Identify the type and periodicity of information needed from DER to improve load forecasting and generator modeling Account for the uncertainty introduced by integration of variable generation and essential reliability services Western Electricity Coordinating Council

Western Interconnection Essential Reliability Services Western Electricity Coordinating Council

Essential Reliability Services - Action All new resources should have the capability to support voltage and frequency - FERC Forecasting, visibility, and participation of DERs as an active part of the electric grid – Utility Planners and WECC Western Electricity Coordinating Council

Western Electricity Coordinating Council Clarify the Three Rs Planning Regions Responsibility WECC Role Stake-holder Relationship Western Electricity Coordinating Council

Questions Dave Angell dangell@idahopower.com (208) 388-2701 Here is what you should expect to see in December A three-year work plan Western Electricity Coordinating Council