James Wells – PWG Chair May 25, 2018 PWG Review Summary James Wells – PWG Chair May 25, 2018 Western Electricity Coordinating Council

Western Electricity Coordinating Council PWG Membership Western Electricity Coordinating Council

PWG Membership & Charter Currently Two Open Spots One open designated spot from Rocky Mountain Region One at large spot Charter review and membership evaluation to accommodate additional Reliability Coordinators in the Western Interconnection. Membership & Voting could be expanded: One from each RC One from each RSG Any interest or recommendations of candidates for membership please contact WECC Staff Liaison or PWG Chair Western Electricity Coordinating Council

PWG Action Item Tracking New form for tracking action items developed Working with WECC IT to create location for easy access New drop down for action items Western Electricity Coordinating Council

Western Electricity Coordinating Council BAL-004-0 Retirement Officially Retired FERC Approved Retirement BAL-004-0 Manual Time Error Correction Effective April 1, 2017 NAESB has informational filing to retire WEQ-006 Manual TEC Business Practice Standard Opportunity for FERC and NASBE to communicate better Western Electricity Coordinating Council

Western Electricity Coordinating Council BAL-004-0 Retirement Delta TE still required to be tracked for WI BAL-004-WECC-2 ATEC Peak RC and Avista (Western Interconnection time monitors) have upgraded system clocks and are ready to capture larger accumulated TE Recommended: Entities review system clocks and processes. Accumulated time error could exceed current clock capabilities Peak RC transmits accumulated TE and delta TE via ICCP if needed by entities Western Electricity Coordinating Council

Western Electricity Coordinating Council BAL-004-0 Retirement PWG encourages WECC & Peak RC to publish formal communication NERC Guideline exists. Peak RC as regional time monitor has ability to call for Manual Time Error Correction for reliability purposes. MTEC could be called upon via operating instruction or directive No document from Peak has been published defining any reliability reasons for MTEC PWG views MTEC as a commercial service that is not tied to reliability and accurate time can be obtained from alternative sources. Other Reliability Standards establish criteria and limits for frequency. As such PWG does not anticipate Peak RC to call for MTEC in the future. Western Electricity Coordinating Council

Western Electricity Coordinating Council BAL-004-WECC-3 WECC-0124 SAR & Drafting Team Scope: Addressing R1 regarding PII reconciliation to WIT tool Standard tool (one), regardless of multiple RC NERC Board Approved. Pending FERC Approval. Recommendation: Entities not using WIT for PII calculation and PII accumulation should review calculations and processes Reconcile with WIT prior to standard becoming enforceable. Western Electricity Coordinating Council

Western Electricity Coordinating Council BAL-003-1.1 SAR NWPP submitted technical document to support the SAR 2 SARs on the NERC level have been combined Drafting team actively working on BAL-003 standard update Identifies potential reliability gaps in standard Real Time Reliability, Event Selection, Measurement, Assumptions behind the standard Phase 1 - Focus on IFRO calculation and fix administrative issues with attachments Timeline/Goal: Draft out for comment in October Timeframe Western Electricity Coordinating Council

Western Electricity Coordinating Council BAL-002-3 (SAR) NERC SAR Proposing BAL-002-3 Goal: Provide clarification when BA is exempt from meeting 15 minute DCS rule Passed Ballot Drafting Team will receive and review comments in the next few weeks Future Action: Final posting and NERC 10 day ballot Western Electricity Coordinating Council

BAL-002-WECC-2 Field Trial Field Test planned for 2 years 1 Year of data collected *** DCS events since implementation of Field Test (May 1, 2017) Allowing entities to determine appropriate spin % for their system has not degraded DCS performance 100% pass rate of DCS events Western Electricity Coordinating Council

BAL-002-WECC-2 Field Trial Entities have been carrying over 50% of MSSC as spinning reserve (at least during reportable disturbances) This does not necessarily mean entities have been carrying 50% spinning reserve at all times Spinning reserve may be carried for other reasons BAL-003-1.1 FRO Variable based generation resources Western Electricity Coordinating Council

BAL-002-WECC-2 Field Trial WECC-0115 Drafting Team to reconvene to prepare report to move forward with retirement of R2 Field Test Active for 1 more year Goal: Retirement of R2 within next year Concern the field test data could be misinterpreted in efforts to retire the BAL-002-WECC-2 R2 Field Test may need to be extended until FERC approval of BAL-002-WECC-2 R2 retirement Western Electricity Coordinating Council

BAL-002-WECC-2 Field Trial Entity # # DCS Events Average Loss (MW) Average Contingency Reserve Obligation (MW) Average Spin (MW) % Pass Entity 1 N/A 100% Entity 2 3 509 554 400 Entity 3 2 505 585 1022 Entity 4 Entity 5 34 626 3511 6204 Western Electricity Coordinating Council

BAL-002-WECC-2 Field Trial # of events Average Loss (MW) *** Western Electricity Coordinating Council

PII – NSI Calculated Ramp Proof of Concept with data from May & June 2017 data from PWG member BA Minimal impact or benefit Potentially extremely costly to implement PWG no longer pursuing Western Electricity Coordinating Council

PII – Alberta Islanding PII = (1-Y) * (IIactual - Bi * ΔTE/6) Alberta Islanded from the Western Interconnection starting October 2nd to October 6th Even though Alberta NAI and NSI were 0 WIT did not recognize them as being islanded Due to the bias term in PII, Alberta erroneously accumulated PII Western Electricity Coordinating Council

PII – Alberta Islanding Retroactive Fix: OATI made a one time PII change in WIT for Alberta Corrective Action Going Forward: Alberta uses a fixed bias, investigating capability of sending fixed bias hourly via EIDE protocol where dispatchers could update bias in real time to 0 when islanded PWG Guideline Development Developing guideline and best practices for entities to utilize to prevent erroneous PII accumulation during islanding Evaluating PII accumulation for offline generation only BAs Once developed will be channeled through WECC OC for review and approval Western Electricity Coordinating Council

Event/Disturbances & Schedule Cuts Several PDCI Blocks in 2017 Resulting in NW RAS Generation Drop Canadian/United States Separation Event During events prolonged frequency events were experienced as a result of delayed schedule cuts Western Electricity Coordinating Council

Event/Disturbances & Schedule Cuts Ongoing analysis of PDCI and other events PWG defining problem and scope with examples Planned coordination with ISAS to develop best practice guideline for schedule cuts following an even/disturbance Western Electricity Coordinating Council

Western Electricity Coordinating Council ERSWG Measures Essential Reliability Service Work Group Measures Voltage Control Frequency Response Load and Resource Balancing Inertia Trends over time as generation portfolio changes Net Ramp and Demands Curves Rate of Change of Frequency (RoCoF) Western Electricity Coordinating Council

Western Electricity Coordinating Council ERSWG Measures Goal is not to create more work, but to interpret/validate what NERC is doing Make sure we can advise EPAS and OC how control performance is trending Western Electricity Coordinating Council

Patterns of Frequency Deviation PWG is evaluating time of day patters for frequency deviation PWG will be exploring these trends further and with more depth Solar generation Wind generation ACE Inertia (Wester Interconnection, Southern Area vs Northern Area) Developing formal request to Peak RC Capture additional data (inertia, non-synchronous generation, etc) by BA/region. PWG is in the discovery phase, has not seen this type of analysis performed Western Electricity Coordinating Council

Patterns of Frequency Deviation Western Electricity Coordinating Council

WECC Performance Charts Western Electricity Coordinating Council

Western Electricity Coordinating Council Accumulated TE Trend Western Electricity Coordinating Council

Number of TE Corrections Western Electricity Coordinating Council

Duration of TE Correction (Hours) Western Electricity Coordinating Council

Western Electricity Coordinating Council On and OFF Peak ABS Western Electricity Coordinating Council

Interconnection Ave CPS1 Trend Western Electricity Coordinating Council

Western Electricity Coordinating Council BAAL Exceedance 10-14 min Western Electricity Coordinating Council

Western Electricity Coordinating Council BAAL Exceedance 15-19 min Western Electricity Coordinating Council

BAAL Exceedance > 20 min Western Electricity Coordinating Council