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Study Results PC8-PC16 System Stress Tests This slide deck contains results from the 2012 TEPPC Study Program related to the various stress tests performed on the 2022 Common Case. The results of the studies are shown along with an indicator to show the robustness of transmission in that area. Slide 2 2 Description and goal Assumptions Results 10-Year Stress Test Results Slide 3 Study Description and Goal Slide 4 4 PC8-PC15 Add 6,000 GWh Renewables PC16 RPS Off-Ramp Stress Test Cases two concepts Slide 5 5 Evaluate systems ability to integrate and deliver added resources to load, subject to transmission constraints Stress the system Proxy for o High gas (makes RE more competitive) o High load (requires higher RPS and more RE) o CO 2 Policy (less thermal, more RE) o Increase in RPS (more RE) Studies are designed as indicators Summary Examine the Robustness of the Power Grid Help us to understand how the system may behave under a variety of future conditions. This is robust planning. Slide 6 6 No additional transmission added Small addition of RE will not solely justify addition of large interregional project Capital cost analysis will not be performed as it is outside the intent of the study Caveats Slide 7 Study Assumptions Slide 8 Stress Test: PC8-PC15 Resource Selection Process Calculate ratios of renewables in TEPPC 2022 Common Case Do not include existing resources Do not include DG IRP and LRS data Apply ratio to future build-out of 6,000 GWh Concept: past trends are best the representation of what could be added to each state More recourses available than what is identified in WREZ More granular information from CPUC/CAISO Locate resources using WREZ Extrapolation Method Slide 9 Resources from CPUC scenario that were originally decremented for Common Case net-short are added Solar +1000 GWh Geothermal -1000 GWh Evaluated as one 6,000 GWh study. Resource split 50/50 in each Basin state. Per CPUC Slide 10 10 Stress Test: PC16 Resource Removal Process WECC Class Explanation Class 0Existing Class 1Under active construction. Projected to be in-service within five years. Class 2Additions that were reported to have: 1)Regulatory approval (or in review) 2)Signed Interconnection agreement 3)Expected on-line date within seven years Class 3Meet NERC criteria for Future Planned or Future Other Resources but that do not meet Class 1 or 2 Class 4Meet NERC criteria for Conceptual Resources WECC LRS Data Collection Manual Remove Slide 11 Slide 12 Common Case Results Refresher Slide 13 Selection based on Regional Significance Construction Status Financial Indicators Implementation Indicators Slide 14 Potential area of concern High utilization can be explained or is expected Slide 15 Flow: BC to NW Flow: NW to BC Slide 16 IPP generation Slide 17 Common Trends System seems to be fairly robust given the CCTA and Common Case starting point of system utilization. 1 When more renewable energy is added to the system, gas appears to be the marginal resource in all studies (except Montana), given our current price assumptions. CA gas units are most marginal. 2 Heavier utilization, not much congestion (i.e., the transmission system still permits economic transfer). 3 Slide 18 California Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Stress test had only minor impact on transmission utilization. Including additional generation in CA reduces requirement for imports. Slide 19 Slide 20 Slide 21 Arizona Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Increase in AZ to CA imports. Congestion on P29. More detailed analysis required. Slide 22 Slide 23 Slide 24 New Mexico Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Increase in P22 (SW of 4- Corners) utilization, but not congested. Other paths are not heavily impacted. Slide 25 Slide 26 Slide 27 Wyoming Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Some sensitivity observed P29 and P36. Large change in RMPA to Basin flow. Slide 28 Slide 29 Slide 30 Montana Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator P8 congested as a result. MT system is relatively isolated and is easily stressed. Slide 31 Slide 32 Slide 33 Washington Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Small impact. Slide 34 Slide 35 Slide 36 Oregon Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Very little congestion observed. Slide 37 Slide 38 Slide 39 Basin Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Increased utilization, but not much congestion. Slide 40 Slide 41 Slide 42 RPS Off-Ramp Stress Test AssumptionsTransmission Results Generation ImpactsKey Finding Robustness Indicator Decrease in congestion outweighs increase. Side bar: Is it apparent that our system designed for RPS compliance is highly versatile and can accommodate more local generation? Slide 43 Slide 44 Slide 45 Quick Summary Robustness Indicator NA Slide 46 Questions or thoughts on this study?