Mgr. Interconnection Reliability Initiatives ECC Update Peak RC Users Group October 25, 2017 Jeremy West Mgr. Interconnection Reliability Initiatives

UFMP Migration Update Successful migration June 27th Reminder of primary changes with ECC UFMP: Factors based off real-time topology More granular mapping

UFMP Migration Update Events Since Migration: June 27-30: July: Three Step 3 events (17.28 hours) July: One Step 2 event Sixteen Step 3 events (52.95 hours) Six Step 4 events (1055.6 MW relief required) August: Thirteen Step 4 events (1472.2 MW relief required)

UFMP Migration Update Events Since Migration: September October 1-15 Two Step 2 events Five Step 3 events (11.9 hours) Forty-two Step 4 events (7844.2 MW relief required) October 1-15 One Step 1 event (test from Peak) Four Step 3 events (6.1 hours) Ten Step 4 events (1075 MW relief required)

UFMP Migration Update USF Event Count by Qualified Path Path 30 = 20 (5 Competing Path) Path 31 = 21 (6 Competing Path) Path 36 = 39 Path 66 = 24

Peak will continue to analyze UFMP results post-migration UFMP Migration Update ECC Migration Benefit? Scheduling practice changes? Peak will continue to analyze UFMP results post-migration

UFMP Migration Update Issues since Migration: Cleanup on USF event messaging Research on USF events Relief provided Competing path issues USF Issuance Performance Mappings (ongoing)

Mappings Installed mappings with BAs regularly impacted by USF Step 4 events Installed approximately 850 linkages between sources/sinks and granular factors (service points) REMINDER: Peak is continuing to verify and update mappings; second round focused on sinks

Mapping Effort Example BA Service Point Name WSM Substation WSM Unit AZPS PALOVERDE_GEN PALVDGEN UPLGEN1 UPLGEN2 UPLGEN3 Category BA PSE Type Name Service Point 1 AZPS APS01 Source PALOVERDE PALOVERDE_GEN AZUS01 BANN01 BURBT4 CLTN00 EPEC01 GLNDGL IIDMA1 LAWM01 LDWP PASM01 PNMMS1 RVSRV SCETAG SRP SRPMST VERNON Type of Source 1 Generation at a single point 2 Groups of generators 3 System Level 4 Tie Points 5 Non-Energy 6 Not modelled in WSM 7 Missing in WSM (ticket entered) 8 Sink registered as both 9 Sink point

ECC Major Project Phases June 2016: Current Hour Situational Awareness Provide visualization of impact “layers” on Elements. Increase knowledge of e-Tag impacts. Provide ACE/Gen. re-dispatch analysis capability. Inform mitigation plans with BAs and TOPs.  June 2016 June 2017: WebSAS Integration  June 2017 Move UFMP support from webSAS to ECC. Base curtailment factors on Real-time conditions. Implement more granular mappings. Q2 2018: Future Hour Situational Awareness Key Talking Points: RT Situational Awareness – Carry over from previous slide. Continue to emphasize the value of a tool that provides situational awareness of Real-time flows and impact layers across the ENTIRE Western Interconnection. WebSAS Integration – No functionality lost. More accurate calculations through use of RT data. WebSAS WILL be retired upon completion of this phase. Future-Hour – Same functionality extended to future hours to identify/address potential issues. Expanded Congestion Mgmt. – Will be thoroughly discussed and vetted. Not intended to provide a “magic button” to address all congestion issues. Rather, looking to expand tool functionality to provide reliability entities with a method to manage congestion for any Facility via an agreed upon methodology. Apply forecast and outage data to provide look-ahead visualization of potential SOL exceedances. Provide time to adjust system prior to actual events. Early 2019: Expanded Mitigation Expand SOL management functionality to all defined Elements. Monitor and mitigate seams issues between BAs and Markets by determining relief obligations. Work with stakeholders on final design.

≥95%?? Future Hour Situational Awareness https://safeordangerous.com/139/safe-live-near-power-lines ECC future hour will use forecast and outage data to predict near-future flows

Future Hour Situational Awareness Key Inputs: Forecast data – generation and load Outage data – IRO-017 data Outputs: Now H+1 H+2 Outages Outages

Future Hour Situational Awareness

Industry Changes Drive ECC Need Seams issues https://www.westerneim.com/Pages/About/default.aspx https://www.wecc.biz/Administrative/Balancing_Authorities_JAN17.pdf

ECC Element Definition

Expanded Mitigation ECC Engine Elements No Yes No Relief Obligation Can be through: RTCA (RT) OPA (Near Term) Studies (Long Term) Element Exceeding Threshold 100% Normal Lim PTDF 100% Highest Lim OTDF Do flows from non-native BA/TOP entities have x% impact to Element? BA/TOP resolve individually No Yes Does BA/TOP have x% (or y%) impact on Element? Did BA/TOP provide relief in timely & appropriate manner? No Relief Obligation Assign Obligation based on x% No Additional Action Relief Assignment via Peak-led instructions

115 kV Line FLO 345 kV Line (related to Qualified Path) Expanded Mitigation 115 kV Line FLO 345 kV Line (related to Qualified Path) Post-Contingency Flow 116.5 Element Limit (100% H.A.) 77 Relief (95% Limit) 43.35

Expanded Mitigation

115 kV Line FLO 345 kV Line (related to Qualified Path) Expanded Mitigation Relief Obligation at Various TDFs 115 kV Line FLO 345 kV Line (related to Qualified Path) Post-Contingency Flow 116.5 Element Limit (100% H.A.) 77 Relief (95% Limit) 43.35 5 Percent Impact (Percent) CISO 2.30 (9.3) PACE 3.90 (15.8) PNM 1.50 (6.1) PSCO 1.40 (5.7) SRP 5.50 (22.3) WACM 10.10 (40.9) TOTAL 24.7 All e-Tag or ACE 10 Percent NONE Impact cannot meet Relief

115 kV Line FLO 345 kV Line (related to Qualified Path) Expanded Mitigation Relief Obligation at Various TDFs 115 kV Line FLO 345 kV Line (related to Qualified Path) Post-Contingency Flow 116.5 Element Limit (100% H.A.) 77 Relief (95% Limit) 43.35 3 Percent 1 2 5 6 7 GTL ACE Impact (%) CISO 3.90 5.80 9.7 (21.0) NWMT 1.30 1.3 (2.9) PACE 0.90 1.40 11.80 14.1 (31.0) PNM 0.30 0.20 1.00 1.5 (3.3) PSCO 1.4 (3.1) SRP 5.50 5.5 (12.0) WACM 0.40 10.40 0.50 0.70 12.0 (26.0) Total 5.20 7.00 1.60 28.70 2.10 45.5

Expanded Mitigation Potential BA View for Relief Obligation For discussion purposes – display design not finalized

Expanded Mitigation

Ultimate goal of ECC expanded mitigation phase is: Relief obligation assigned to stakeholders who have impact on flow exceedance Agreement on the “authority” (standards, agreements, etc.) to enforce obligation

Key Project Activities Expanded Mitigation Key Project Activities November 6-7: ECC Task Force meeting (Portland) Complete ECC “final state” documentation with Task Force input November 8 (target) Post ECC “final state” documentation for review and 30 day comment period by industry via Peak MAC (may include industry outreach) December Peak Board / MAC meetings Provide progress update

Thank you! https://www.integrity.oati.com ECC@peakrc.com Jeremy West jwest@peakrc.com (970) 613-3542