2018 Gridliance High Plains Planning Study Final Transmission Plan

April 1, 2019

2018 GridLiance High Plains Planning Study Final Transmission Plan

Transmission Planning

April 1, 2019

Executive Summary

GridLiance High Plains LLC (GridLiance) performed its 2018 annual system assessment in compliance with the GridLiance Open Access Transmission Tariff Attachment K requirements. This assessment utilized the GridLiance Reliability Criteria in addition to North American Electric Reliability Corporation (NERC) and Southwest Power Pool, Inc. (SPP) criteria and protocols to address the unique needs and conditions of the GridLiance system. GridLiance identified reliability needs in the Oklahoma Panhandle and East Central Oklahoma regions, evaluated mitigation options, and estimated construction cost and timing.

Through the 2018 Local Planning Process (LPP), GridLiance has selected mitigations to the identified reliability needs over the 10-year study horizon. These recommended mitigations are listed in Table 1 below. GridLiance recommends for budgetary approval approximately $14 million of those upgrades in the next 2 years, as shown in Table 2. The remaining recommended mitigations will undergo continued evaluation in the next LPP study.

Upgrades Location Recommendation Close Egypt Switch after all necessary system East Central Submit to SPP for coordination & modifications and relay coordination within and Oklahoma recommend for budgetary approval external to the GridLiance system takes place1 Oklahoma Submit to SPP for coordination & Build new Y-Road Switching Station, 3-terminal ring bus Panhandle recommend for budgetary approval Retire Eva Regulator + Install 25-30 MVAR reactive Oklahoma Submit to SPP for coordination & support in Western Panhandle region2 Panhandle recommend for budgetary approval Add station and 25 MVAR reactive support at/near Oklahoma Submit to SPP for coordination & Turpin Panhandle recommend for budgetary approval New approximately 8.5-mi 115 kV line from Red Devil to Oklahoma Enel’s Goodwell Wind, station expansion, and rebuild Y- Continue Evaluation in 2019 LPP Panhandle Road-Goodwell-Red Devil 115 kV lines New approximately 25-mile 115 kV line from Dry Trails Oklahoma to new station tapping Liberal-Texas County Continue Evaluation in 2019 LPP Panhandle Interchange 115 kV line near Hooker, OK New approximately 30-mile 115 kV line from Rose to Oklahoma Continue Evaluation in 2019 LPP Sunflower’s Liberal Panhandle Install voltage support near Powell Corner 115 kV - 14.4 Oklahoma Continue Evaluation in 2019 LPP MVAR reactive support Panhandle Table 1: GridLiance 2018 LPP Recommended Mitigations

1 There are on-going interconnection discussions with other Transmission Owners for this project. Details on other equipment will be added upon execution of agreements. 2 Determination of size and placement of reactive support will be performed in a separate Electromagnetic Transients Program (EMTP) study.

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Project Cost Est. Proposed Upgrades Location Driver (millions) ISD Close Egypt Switch after all necessary system East Central modifications and relay coordination within and MW-Mile TBD 2019 Oklahoma external to the GridLiance system takes place Oklahoma Build new Y-Road Switching Station, 3-terminal ring bus Operational $4.5 2019 Panhandle Retire Eva Regulator + Install 25-30 MVAR reactive Thermal, Oklahoma $4.0 2020 support in Western Panhandle region Voltage Panhandle Add station and 25 MVAR reactive support at/near Oklahoma Voltage $5.0 2020 Turpin Panhandle Table 2: Projects Recommended for Construction

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OVERVIEW

GridLiance performed its annual system assessment in compliance with the GridLiance Open Access Transmission Tariff Attachment K requirements. This report outlines the study assumptions, findings, and mitigations resulting from the 2018 GridLiance Local Planning Study. The assessment utilized GridLiance’s Reliability Criteria, in addition to NERC and SPP criteria and protocols, to address the unique needs and conditions of the GridLiance system. As outlined in the Attachment K, GridLiance conducts an annual assessment of the GridLiance facilities’ current and expected operations thereby identifying actions needed to: (1) maintain the reliability of the GridLiance facilities in an economic and environmentally acceptable manner; (2) ensure that the load, transmission, and interconnection needs of GridLiance and GridLiance customers are met and services are provided in a manner that treats similarly situated customers comparably; and (3) meet needs driven by Public Policy requirements established by state or federal laws or regulations. As part of the system assessment, GridLiance has developed a plan to meet anticipated current and future transmission needs of its customers who are receiving generator interconnection services and transmission services on or across GridLiance transmission facilities. The GridLiance facilities under this study include its 115 and 69 kV Oklahoma panhandle facilities, 69 kV facilities in Nixa, Missouri, and the 138 kV East Central Oklahoma facilities that GridLiance expects to acquire this year.3 The geographic regions are depicted respectively in Figure 1, Figure 2, and Figure 3.

Figure 1: GridLiance Oklahoma Panhandle Service Area

3 In March 2019, after GridLiance’s LPP analysis was complete, GridLiance’s application to acquire the East Central Oklahoma Facilities from People’s Electric Cooperative was denied by Federal Energy Regulatory Commission (FERC) without prejudice. GridLiance plans to file another application in 2019 requesting approval of the acquisition.

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Figure 2: GridLiance Missouri Service Area

Figure 3: GridLiance East Central Oklahoma Service Area

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Modeling Assumptions

For this assessment, GridLiance used the most recent SPP 2018 Integrated Transmission Planning Near-Term (ITPNT) Scenario 0 (S0) and Baseline Reliability4 (BR) models as a study starting point. These cases are released every year and contain existing SPP transmission topology and any upgrades or facilities that have been approved for construction. GridLiance made modelling changes to accurately reflect current GridLiance topology and load forecasts as well as recently-announced nearby generation retirements. In addition to correcting existing topology in the SPP models, GridLiance modelled planned construction projects that have been announced since the 2018 ITPNT cases were finalized. These projects include the following:

• Panhandle Reliability Project (In-service date (ISD) June 2019)- construct a new 115/69 kV substation and 20 miles of new 115 kV transmission. The new 115/69 kV substation called Panhandle will bisect the Thrash to Cougar 69 kV transmission line one mile west of Thrash. This will create two new breakered 69 kV line sections, Powell Corner to Panhandle and Panhandle to Cougar. The new 115 kV transmission line will connect Powell Corner to Panhandle. • Second Cole 115/69 kV Transformer (ISD December 2019)5- Add second 115/69 kV 39.5 MVA transformer at Cole substation. • Nixa Espy- Downtown 69 kV Reconductor (ISD December 2019)- GridLiance received an NTC to reconductor its existing Espy to Downtown 69 kV line. • James River Reconfiguration (ISD June 2018)- City Utilities announced adding a second 161/69 kV transformer at its James River station and retiring generation units 4 and 5.

These updated models were used as base cases for this study. Near-term and long-term case years were studied to account for a variety of system conditions. GridLiance also studied summer high load cases with abnormal weather peak load in compliance with its Reliability Criteria.6 This abnormal weather peak load refers to the forecasted normal peak load for an average year plus 10% which is referenced as summer high load (SHL) in this report. GridLiance studied generation sensitivities dispatching generation at Centrahoma and States Edge. Since load served from the GridLiance facilities is at its highest during summer peak conditions, the following years and cases identified in Table 3 were studied for this assessment.

4 S0 assumes projected usage of long-term firm transmission service between SPP customers, dispatching each entity’s generation to meet their load and obligations. S0 emphasizes high conventional generation commitment and dispatch. Renewable generation is set to match the Model Development Working Group (MDWG) 2017 models. BR assumes expected usage of long-term firm transmission service usage. Renewable resources are dispatched at each facility's latest five-year average for the SPP coincident summer peak, not to exceed each facility's firm service amount. 5 GridLiance is currently coordinating with SPS on project construction timing. 6 GridLiance Reliability Criteria: GridLiance OASIS>> Transmission Planning>> GridLiance Reliability Criteria

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Year Season Scenario 0 & BR Sensitivity Cases Year 1(Current+1) Light load, Summer peak   Year 4 Summer peak   Year 9 Summer peak   Table 3: Steady State Annual Planning Study Models

Study Methodology

This study assessed the GridLiance system performance using its Reliability Criteria, in addition to the NERC Reliability Standard TPL-001-4 and SPP Planning Criteria. Steady state analysis was conducted under normal operating (P0) conditions and contingency outage events (P1-P7). Local contingencies 69 kV and above defined by GridLiance and contingencies posted by SPP that may impact the GridLiance system were included in the steady state analysis. The transmission system is expected to perform reliably under a variety of cases while remaining within defined thermal and voltage limits as set forth in GridLiance’s Reliability Criteria. GridLiance monitored transmission facilities 69 kV and above during normal and contingency conditions for first tier zones:

• SPS- 1502 and 823 • SPA- 521 • SPRM- 1583 • WFEC- 590

Thermal loading shall not exceed 100% of the normal (Rate A) or contingency (Rate B) rating. Voltage limits were monitored in accordance with GridLiance Reliability Criteria.

Issue Identification

The results in this report are focused on the base and summer high load cases. The studied generation sensitivities with dispatched Centrahoma and States Edge generation did not create any new thermal or voltage violations nor worsen those violations identified in the base and summer high load models. Additionally, GridLiance did not observe any thermal overload or voltage issues in the 2019 light load cases. External issues identified on monitored first tier facilities are included in Appendix B.

Thermal Overloads In the Oklahoma Panhandle region, GridLiance observed thermal overloading on the 15 MVA Eva Regulator in the 2027 summer base case and all summer high load cases under normal operating conditions. Additionally, all base and summer high load cases reported thermal overloading on this facility with the outage of the Cougar to Panhandle 69 kV circuit. The Hovey to Thompson 69 kV circuits reported

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thermal overloading in the 2027 summer high load case with the outage of the Texas County Interchange to Powell Corner 115 kV circuit.

In the Nixa Missouri region, GridLiance observed thermal overloading on the 20 MVA Southwestern Power Administration (SPA) Nixa 161/69 kV transformer due to the outage of the 70 MVA Nixa 161/69 kV transformer in all base and summer high load cases. SPA has planned transformer upgrades with an ISD of 2021 that would mitigate this overloading. The 69 kV line from the SPA Nixa station to the GridLiance Espy station had thermal overloading in the base 2027 summer case as well as the 2022 and 2027 summer high load cases with the outage of the new 150 MVA James River 161/69 kV transformer 2. These overloads are due to terminal equipment limitations in the SPA Nixa substation. GridLiance has shared these results with SPA and will work to coordinate the appropriate mitigation as 2022 approaches.

Table 4 and Table 5 contain the thermal loadings observed for the above facilities in base and summer high load models.

From Bus To Bus Base Load-Thermal Loading % Ckt ID Contingency Number Name kV Number Name kV 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522922 EVA-W 2 69 523051 TC-EVAREG 2 69 1 Base Case 91.64 96.2 100.41 93.58 96.7 522922 EVA-W 2 69 523051 TC-EVAREG 2 69 1 P1.2-COUGAR-PANHANDLE 69 kV 107.91 111.96 118.12 108.32 112.04 505496 NIXA 5 161 3WNDTR NXA X2 WND 2 1 P1.3-SINGLE 505496-505501-505497(1) 101.57 105.47 122.29 100.00 105.12 505501 NIXA 2 69 505543 NX ESPY2 69 1 P1.3-SINGLE 549903-549961-549945(1) - - 104.83 - -

Table 4: Base Load Thermal Overloads7

From Bus To Bus Summer High Load-Thermal Loading % Ckt ID Contingency Number Name kV Number Name kV 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522922 EVA-W 2 69 523051 TC-EVAREG 2 69 1 Base Case 101.47 103 108 103.5 104 522922 EVA-W 2 69 523051 TC-EVAREG 2 69 1 P1.2-COUGAR-PANHANDLE 69 kV 120.39 124.82 132.79 120.74 124.9 523001 TC-HOVEY 2 69 523065 TC-THOMPSON2 69 1 P1.2-TX CO - POWELL CORNER 115 kV - - 101.17 - - 523001 TC-HOVEY 2 69 523065 TC-THOMPSON2 69 2 P1.2-TX CO - POWELL CORNER 115 kV - - 101.17 - - 505496 NIXA 5 161 3WNDTR NXA X2 WND 2 1 P1.3-SINGLE 505496-505501-505497(1) 106.56 110.77 128.13 104.61 110.41 505501 NIXA 2 69 505543 NX ESPY2 69 1 P1.3-SINGLE 549903-549961-549945(1) 95.00 101.00 109.13 96.00 100.00

Table 5: Summer High Load Thermal Overloads

Voltage Violations GridLiance did not observe voltage violations in the Nixa Missouri and East Central Oklahoma regions on monitored GridLiance facilities8 under normal operating and contingency outage conditions. The following voltage results are focused on GridLiance facilities in the Oklahoma Panhandle region.

During normal conditions, GridLiance observed voltage below the minimum 0.95 (p.u) on the Eva Regulator in all base and summer high load cases. Additional buses along the Cougar to Blade 69 kV circuit showed low voltage during 2022 and 2027 summer high load cases. Table 6 shows the base case voltage violations for each base and summer high load case year.

7 Table cells with "-” indicate that the results are well within limits set by GridLiance Reliability Criteria. 8 Issues identified on first tier facilities due to external outages are included in Appendix B.

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Oklahoma Panhandle-Lowest Voltage (p.u) P0 Conditions Base Load Summer High Load Bus Number Bus Name Bus kV 2019 S 2022 S 2027 S 2019 S 2022 S 2027 S 523051 TC-EVAREG 2 69 0.946 0.922 0.919 0.929 0.908 0.902 522909 FELT 2 69 - - - - 0.944 0.936 522919 COUGAR 2 69 - - - - 0.949 0.942 522920 ELMS_TAP 2 69 - - - - 0.949 0.942 522940 WILDCAT 2 69 - - - - 0.949 0.942 522949 ELMS 2 69 - - - - 0.949 0.942 Table 6: Lowest Voltage (p.u) Violations during P0 Conditions

Section 2.0 System Voltage Limits of the GridLiance Reliability Criteria specifies the minimum voltage of 0.93 (p.u.) and a maximum voltage deviation of 7% for contingency outage events. GridLiance observed low voltage and voltage deviation violations in the Oklahoma Panhandle region for various P1-P7 contingency events.

Table 7 shows the lowest voltage (p.u.) reported for each contingency event in each base and summer high load case year.

Oklahoma Panhandle-Lowest Voltage (p.u.) P1-P7 Conditions Base Load Summer High Load Contingency Low Voltage Impact 2019 S 2022 S 2027 S 2019 S 2022 S 2027 S P2.2-TXCOUNTY- 115 kV BUS System voltage collapse 0.00 0.00 0.00 0.00 0.00 0.00 P7-TXCOUNTY-SUB System voltage collapse 0.00 0.00 0.00 0.00 0.00 0.00 P2.2-TXCOUNTY-69 kV BUS Widespread, Cougar to Beard subs 0.85 0.83 0.81 0.86 0.84 0.82 P2.2-HOVEY-69 kV BUS Cougar-Blade 69 kV 0.90 0.90 0.87 0.88 0.86 0.84 P7-HOVEY-SUB Cougar-Blade 69 kV 0.90 0.88 0.86 0.88 0.86 0.84 P1.2-COUGAR-PANHANDLE 69 kV Cougar-Blade 69 kV 0.89 0.87 0.85 0.86 0.81 0.78 P1.2-HOVEY-BLADE 69 kV Cougar-Blade 69 kV 0.90 0.88 0.88 0.88 0.86 0.85 P1.2-POWELL CORNER-TX CO 115 kV Western loop from PC to Panhandle 0.91 0.89 0.87 0.90 0.86 0.84 P2.2-COLE-115 kV BUS Jefferson-Elmwood 69 kV 0.76 0.72 0.68 0.69 0.65 0.61 P2.2-COLE-69 kV BUS Jefferson-Turpin 69 kV 0.90 0.87 0.87 0.87 0.85 0.84 P7-COLE-SUB Jefferson-Turpin 69 kV 0.89 0.87 0.85 0.86 0.84 0.82 P7- HITCHLAND SUB Widespread, Cougar to Elmwood subs 0.80 0.77 0.76 0.62 0.55 0.49 P1.3-115/69-COLE-XFMR-50MVA Jefferson-Elmwood 69 kV 0.77 - - 0.72 - - P1.4-TXCOUNTY-69 KV SWSHNT Nearby PC and Hvy 69 kV - - - - 0.92 0.91 P1.2-TX CO-HITCHLAND 115 kV CKT 1 Elkhart-Cougar 69 kV - - - - 0.92 0.91 P2.2-THOMPSON-69 kV BUS Cougar-Blade 69 kV - - - - 0.93 0.92 P7-DBL CKT-69kVHOVEY-THOMPSON Elkhart-Cougar 69 kV - - 0.93 - 0.92 0.91 Table 7: Lowest Voltage (p.u) Violations during P1-P7 Contingency Outages

The most severe event being the outage of the Texas County Interchange 115 kV bus. Approximately 120 MW of load is served by this source, resulting in system blackout during an outage. Loss of the Texas County Interchange 69 kV bus results in widespread low voltage and deviation on the north and western system served from Texas County Interchange. GridLiance also observed widespread low voltage and deviation stretching across the entire Oklahoma Panhandle system for the loss of Hitchland 115 kV bus.

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Significant portions of the western Oklahoma Panhandle 69 kV system experience low voltage and deviation due to the outage of Hovey 69 kV bus. This area of the Panhandle system experiences poor voltage support for transmission circuit outage of 69 kV Cougar to Panhandle, 69 kV Hovey to Blade, and 115 kV Powell Corner to Texas County Interchange.

Additionally, GridLiance observed low voltage and voltage deviation violations on the 69 kV system served off Cole 115/69 kV substation for loss of either Cole bus or substation. The 2019 summer case reported voltage drop with the loss of the existing 115/69 kV Cole transformer. GridLiance modelled the incoming second Cole transformer in the 2022 and 2027 models, which mitigates the voltage issues identified in the 2019 summer cases.

GridLiance did not observe any new voltage deviation issues in the summer high load cases. The system voltage is about 2% lower in the summer high load cases, pushing some voltages below the minimum limit that were previously not reported in base cases. Full base and summer high load case voltage results are shown in Appendix A.

MW-Mile Violations GridLiance identified reliability concerns on the transmission system due to long radial circuits serving the portions of the Oklahoma Panhandle with lines terminating at the Dry Trails and Rose substations, as well as the radial circuit terminating at the Monte Vista substation in East Central Oklahoma. There are operational concerns in providing reliable service to load customers on these circuits. The load served off these radial circuits exceeds the limits set by Section 6.0 Transmission Service to Distribution Substations of the GridLiance Reliability Criteria. Specifically, load serving substations served at a transmission voltage shall have at least two sources of transmission service if the MW-mile exceeds 200 MW-mile. This MW-mile calculation is used to measure load loss exposure. Table 8 below shows the existing MW-mile on the circuits to Dry Trails, Rose, and Monte Vista; all circuits exceed the 200 MW-mile criteria. The load values used align with the most recent Network Integration Transmission Service Agreement (NITSA) 10-year forecast for the Oklahoma Panhandle Region and the 2019 load projections received from People’s Electric Cooperative for the East Central Oklahoma region. 9

Station Load (MW) Radial Miles System MW-Mile Dry Trails 26.02 11.85 308.28 Lobo 3.10 7.95 24.64 Total Dry Trails CKT MW-Mile 332.91 Anthony 0.68 14.85 10.10 Rose 7.06 28.50 201.21 Total Rose CKT MW-Mile 211.31 Ahloso 22.81 12.86 293.34 Monte Vista 4.77 18.90 90.15 Total Monte Vista CKT MW-Mile 383.49 Table 8: GridLiance Radial MW-Mile

9 This does not include expected load growth in the region.

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MW Violations GridLiance identified similar reliability issues for load levels between breakers. The load served by circuits that exceeds the limits set by Section 6.0 of the GridLiance Reliability Criteria are shown below in Table 9. There are operational concerns in providing reliable service to load customers on these circuits that exceed a defined load level. Specifically, load service substations served at a transmission voltage shall have at least two sources of transmission service if the amount of load between breakers exceeds 20 MW. The modeled load values align with the most recent NITSA 10-year forecast for the Oklahoma Panhandle Region and the 2019 load projections received from People’s Electric Cooperative for the East Central Oklahoma region.

Station Load (MW) Dry Trails 26.02 Lobo 3.10 Total MW 29.12 Ahloso 22.81 Total MW 22.81 Table 9: GridLiance Load Between Breakers

Other Violations No other criteria violations were identified in this assessment. GridLiance did not identify any transmission needs driven by Public Policy Requirements.

Mitigations

GridLiance has considered various mitigation options for the identified reliability concerns.

Panhandle Oklahoma Region Western Panhandle: To alleviate thermal overloading on the Eva Regulator as described in Table 4 and Table 5 above, GridLiance studied retiring the Eva Regulator.10 GridLiance observed that retiring the Eva Regulator fully mitigated the associated thermal overloading. While retiring the Eva Regulator mitigated low voltage issues associated with certain contingency outage events as shown in Table 10, GridLiance observed additional low voltage issues not mitigated by the retirement. Additionally, GridLiance observed new low voltage violations on the Western Panhandle 69 kV system during normal operating conditions with the retirement. The Eva Regulator provides needed voltage support to the local area; therefore with its retirement, additional equipment would be needed to replace the Eva Regulator to prevent worsening the previously identified low voltage issues on the Panhandle system.

10 Eva Regulator begins overloading at 108% in the Base 2019 summer case during the outage of the Powell Corner to Texas County 115 kV line.

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Retire Eva Regulator in Western Panhandle-Lowest Voltage (p.u) Pre Mitigation With Eva Regulator In Service Retire Eva Regulator Contingency Low Voltage Impact Base 22S SHL 27S Base 22S SHL 27S P2.2-HOVEY-69 kV BUS Eva Reg to Cougar 69 kV 0.90 0.84 - - P7-HOVEY-SUB Eva Reg to Cougar 69 kV 0.88 0.84 - - P1.2-HOVEY-BLADE 69 kV Cougar-Blade 69 kV 0.88 0.85 - - P1.2-TX CO-HITCHLAND 115 kV CKT 1 Elkhart-Cougar 69 kV - 0.91 - - P2.2-THOMPSON-69 kV BUS Cougar-Blade 69 kV - 0.92 - - P7-DBL CKT-69kVHOVEY-THOMPSON Elkhart-Cougar 69 kV - 0.91 - - P1.4-TXCOUNTY-69 KV SWSHNT Nearby PC and Hvy 69 kV - 0.91 - -

Table 10: Voltage Issues Mitigated by Eva Regulator Retirement

With the retirement of the Eva Regulator, GridLiance has identified the need for approximately 30 MVAR of reactive support in the Western Panhandle region. By pairing the Eva Regulator retirement with the additional reactive support, this option alleviates thermal overloads and provides needed voltage support to the nearby system, fully mitigating low voltage for various contingency outage events. Table 11 shows how the studied mitigation options impacted the identified Western Panhandle voltage issues. The determination of size and placement for the recommended reactive support will be performed in a separate Electromagnetic Transient Program (EMTP) study.

Retire Eva Regulator and Add Reactive Support in Western Panhandle-Lowest Voltage (p.u) Pre Mitigation Retire Eva Regulator Add 30 MVAR Reactive Support Contingency Low Voltage Impact Base 22S SHL 27S Base 22S SHL 27S BASE CASE Eva to Cougar 69 kV 0.92 0.90 - - P2.2-TXCOUNTY- 115 kV BUS System voltage collapse 0.00 0.00 0.00 0.00 P7-TXCOUNTY-SUB System voltage collapse 0.00 0.00 0.00 0.00 P2.2-TXCOUNTY-69 kV BUS Widespread, Cougar to Beard subs 0.91 0.87 - - P1.2-COUGAR-PANHANDLE 69 kV Cougar-Blade 69 kV 0.76 0.67 - - P1.2-POWELL CORNER-TX CO 115 kV Western loop from PC to Panhandle 0.88 0.79 - - P7- HITCHLAND SUB Widespread, Cougar to Elmwood subs 0.88 0.56 - - Table 11: Western Panhandle Voltage Mitigation Results

As a near term operating guide, GridLiance studied closing the north to south emergency Panhandle tie. Closing in this tie would mitigate voltage issues in the near term due to bus or substation outage at Hovey, and loss of the Cougar to Panhandle 69 kV circuit. This is not a long-term mitigation as GridLiance Reliability Criteria does not allow for line switching during N-1 conditions. GridLiance will address these issues on the system with the additional reactive support discussed above.

Close Panhandle Emergency Tie-Lowest Voltage (p.u.) Pre Mitigation Contingency Low Voltage Impact Base 22S SHL 27S P2.2-TXCOUNTY-69 kV BUS Widespread, Wildcat to Beard subs 0.86 0.83 P2.2-HOVEY-69 kV BUS Eva Reg to Wildcat 69 kV - 0.92 P7-HOVEY-SUB Eva Reg to Wildcat 69 kV - 0.92 P1.2-COUGAR-PANHANDLE 69 kV Cougar-Blade 69 kV 0.93 0.93

Table 12: Operating Guide-Close Panhandle Emergency Tie

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Eastern Panhandle: GridLiance studied three alternative solutions to mitigate voltage drop during a contingency outage event at Cole Interchange 115 kV bus, 69 kV bus, or the full Cole Interchange substation. The first option was to add a capacitor bank at Jefferson substation. While this option mitigates low voltage seen for loss of the entire sub or the 69 kV bus, there is still low voltage on the eastern 69 kV system during an outage on the 115 kV bus. As a second option, GridLiance evaluated adding either a 20-25 MVAR capacitor bank or SVC at the Turpin 69 kV substation to provide needed voltage support during the Cole Interchange 115 kV bus outage. While a capacitor bank improved the system voltage with the placement at Turpin instead of Jefferson station, it did not fully mitigate the low voltage violations during the Cole Interchange 115 kV bus outage. The addition of a 25 MVAR static VAR compensator (SVC) at Turpin resulted in full mitigation for base 2022 summer load levels, though in the 2027 summer high load case power flow analysis indicated a potential low voltage issue.

A third option is to build a new 7-mile 115 kV line from Ponderosa 69 kV station to Sunflower’s Liberal 115 kV station or a 115 kV tap near Liberal. This would require station expansion at Ponderosa and a 115/69 kV transformer. While this option improved system voltage performance, GridLiance observed low voltage and voltage deviation higher than allowable under GridLiance Reliability Criteria.

As a near term operating guide, closing the Elmwood to Clearlake (WFEC) emergency tie allows load on Balko, Elmwood, Haskell, and Hardesty stations to be served that would otherwise be shed in a 69 kV or full substation outage. This is not a long-term mitigation as GridLiance Reliability Criteria does not allow for line switching during N-1 conditions. GridLiance also recognizes that closing the emergency tie in case of an outage would not be feasible for the increased load levels in the 2027 summer high load case due to limitations on the emergency tie.

Operational Needs: The 115 kV Powell Corner, Red Devil, and Texas County Interchange stations connect at an existing 3-terminal tap. The 3-terminal line configuration exposes approximately 36 miles of 115 kV for any outage along those lines. An outage along these 36 miles affects much of the Western Panhandle system, including all load south of the 3-terminal tap, since the Texas County Interchange station is the primary source for the Panhandle system.11 To address this issue GridLiance’s identified solution is a 115 kV switching station at the 3-terminal tap called Y-Road, which mitigates the operational concern of losing multiple lines and a significant amount of load for a single outage. By reducing the system exposure to 8 miles north to Powell Corner, 10 miles east to Texas County, and 18 miles south to Red Devil, Y-Road station delivers improved reliability to load and increased operational flexibility. During summer peak conditions with the new Y-Road station in service, some load which would otherwise be lost without the Y-Road project may need to be shed during certain contingency events. These issues are presented in tables in Appendix C. These issues can be

11 This includes the largest Panhandle system load, Dry Trails.

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mitigated by the Red Devil and Dry Trails options discussed later in this section and will continue to be evaluated in future LPP studies.

Texas County Interchange Outage: GridLiance has identified a need for a second source for the approximately 120 MW of load currently served by the Texas County Interchange 115/69 kV station. Loss of the Texas County Interchange 115 kV bus or full substation results in system blackout. This presents severe reliability issues for transmission service to this load. GridLiance has studied several new 115 kV connection options and one new 345 kV option to mitigate this need. The 115 kV options provide connections from Red Devil station to sources at Lasley, Hitchland, or Goodwell Wind. These options assume the new switching station at Y-Road to allow the new connection options at Red Devil to eliminate elongating a three-terminal line. The Red Devil connection options to Hitchland and Goodwell Wind fully mitigate the low voltage issues for the outage of Texas County Interchange 115 kV bus. The Lasley 115 kV connection does not provide sufficient voltage support as shown in Table 13 below. A larger 345 kV option is to build a new 16.5-mile 115 kV line from Dry Trails to a new tap station on the Hitchland-Walkemeyer 345 kV line. The new source provided by this solution at Dry Trails fully mitigates system voltage collapse for Texas County Interchange 115 kV bus or full substation outage. The three Red Devil options and Dry Trails option also mitigated the thermal overloads on the Hovey to Thompson 69 kV lines.

Pre Mitigation Red Devil-Lasley 115 kV Red Devil-Hitchland 115 kV Red Devil-GW Wind 115 kV Dry Trails - 345 Tap Contingency Low Voltage Impact Base 22S SHL 27S Base 22S SHL 27S Base 22S SHL 27S Base 22S SHL 27S P2.2-TXCOUNTY- 115 kV BUS System voltage collapse 0.94 0.85 ------Table 13:Voltage-Texas County Interchange 115 kV Bus Outage Mitigations

When considering load growth, the Hitchland and Goodwell Wind options showed low voltage in the Base 2027 summer case for the outage of Texas County Interchange substation as shown in Table 14 below.

Pre Mitigation Red Devil-Lasley 115 kV Red Devil-Hitchland 115 kV Red Devil-GW Wind 115 kV Dry Trails - 345 Tap Contingency Low Voltage Impact Base 22S Base 27S Base 22S Base 27S Base 22S Base 27S Base 22S Base 27S P7-TXCOUNTY-SUB System voltage collapse 0.88 0.83 0.93 0.87 0.95 0.91 - -

Table 14: Voltage-Texas County Interchange Substation Outage Mitigations

GridLiance studied the Red Devil to Hitchland and Goodwell Wind 115 kV connections with an additional 14.4 MVAR of reactive support at Powell Corner to support long term load growth in the region.

Pre Mitigation RD-Hitchland + 14.4 MVAR RD-GW Wind + 14.4 MVAR Contingency Low Voltage Impact Base 27S Base 27S P7-TXCOUNTY-SUB System voltage collapse 0.93 0.95

Table 15: Voltage-Red Devil Connections with Capacitor Bank

GridLiance also evaluated the Red Devil to Goodwell Wind option with the Goodwell Wind generation dispatched at maximum output of 200 MW. Under these conditions, there would be overloading on the existing 115 kV lines from Y-Road to Goodwell and Goodwell to Red Devil for the loss of the

April 1, 2019

Goodwell Wind to Hitchland 115 kV line or a substation outage at Hitchland as shown in Table 16. To mitigate the thermal overloading, this solution includes rebuilding the 115 kV Y-Road to Goodwell line and reconductoring the 115 kV Goodwell to Red Devil line.

From Bus To Bus RD-GW Wind (Max Output) Ckt ID Contingency Number Name kV Number Name kV Base 22S SHL 27S 522912 Y ROAD 3 115 522935 GOODWELL 3 115 1 P7-HITCHLAND-115KV-SUB 133.2 133.0 522930 RED DEVIL 3 115 522935 GOODWELL 3 115 1 P7-HITCHLAND-115KV-SUB 106.5 106.4 522912 Y ROAD 3 115 522935 GOODWELL 3 115 1 SINGLE 523093-523174(1) 133.0 132.8 522930 RED DEVIL 3 115 522935 GOODWELL 3 115 1 SINGLE 523093-523174(1) 106.3 106.2 Table 16: Thermal Overloads-Red Devil to Goodwell Wind 115 kV at Maximum Output

Hovey to Thompson: In the 2027 summer high load case, the Hovey to Thompson 69 kV lines overload for loss of Powell Corner to Texas County Interchange 115 kV circuit. GridLiance considered the following long-term solutions: • Rebuild the double circuit Hovey to Thompson 69 kV lines; and • Build a new 115 kV Hovey to Texas County Interchange line. GridLiance observed the aforementioned Red Devil options and the below Dry Trails options that add a second source also mitigate the thermal overloads on the Hovey to Thompson 69 kV lines. MW-Mile Mitigations: GridLiance identified the following potential solutions to mitigate the MW-Mile violation at Dry Trails substation: • 42-mile 115 kV connection from Dry Trails to Liberal. • 25-mile 115 kV connection from Dry Trails to new tap on Liberal-Texas County Interchange 115 kV line near existing Hooker station. • 18-mile 115 kV connection from Dry Trails to new tap station on the Hitchland-Walkemeyer 345 kV line. The new source provided by this solution also mitigates system voltage collapse for Texas County Interchange 115 kV bus or full substation outage. GridLiance identified the following potential solutions to mitigate the MW-Mile violation at Rose substation:

• 30-mile 115 kV connection from Rose to Liberal. • 20-mile 115 kV connection from Rose to 345 kV Badger station, with additional 345/115kV transformer at Badger or new station. GridLiance identified no-harm to the GridLiance and neighboring systems for the identified MW- Mile solutions. By looping the Dry Trails and Rose substations using the above options, the radial MW-Mile calculations would be reduced well below the 200 MW-Mile criteria, as shown in Table 17.

April 1, 2019

Station Load (MW) Radial Miles System MW-Mile Dry Trails 26.02 0 0.00 Lobo 3.10 0.36 1.12 Total Dry Trails CKT MW-Mile 1.12 Anthony 0.68 2.23 1.52 Rose 7.06 0 0.00 Total Rose CKT MW-Mile 1.52 Table 17: Looped Panhandle Radial MW-Mile

East Central Oklahoma Region MW-Mile Mitigations: In East Central Oklahoma, closing the currently open three-way switch at Egypt would loop the radial facilities serving Monte Vista and Ahloso loads and relieve the MW-Mile violation as shown in Table 18.

Station Load (MW) Radial Miles System MW-Mile Ahloso 22.81 2.86 65.24 Monte Vista 4.77 0.00 0.00 Total Monte Vista CKT MW-Mile 65.24 Table 18: Looped East Central Radial MW-Mile

GridLiance did not identify any thermal or voltage issues due to closing the Egypt switch. At the time of this report, GridLiance is engaged in conversations with interconnected transmission owners to determine the necessary coordination to facilitate closing the Egypt switch. While this low-cost solution mitigates the MW-Mile violation, the load at Ahloso still exceeds the 20 MW load between breaker criteria. No cost-effective solutions were identified to address this issue. The development of an economically feasible mitigation for the MW violation at Ahloso will continue to be evaluated in future LPP studies.

Missouri Region Nearby violations: In the Nixa Missouri region, GridLiance observed thermal overloading on the 20 MVA SPA Nixa 161/69 kV transformer due to the outage of the 70 MVA Nixa 161/69 kV transformer in all base and summer high load cases. SPA has planned transformer upgrades with an ISD of 2021 that would mitigate this overloading.

The 69 kV line from SPA’s Nixa station to GridLiance’s Espy station had thermal overloading in the base 2027 summer case and the 2022 and 2027 summer high load cases with the outage of the new 150 MVA James River 161/69 kV transformer 2. These overloads are due to terminal equipment limitations in the SPA Nixa substation. GridLiance has shared these results with SPA and will work to coordinate the appropriate mitigation as 2022 approaches.

April 1, 2019

GridLiance 2018 LPP Plan

After studying various mitigation options and their impact on the issues identified in this analysis, GridLiance prepared preliminary planning level cost estimates for the mitigation options along with potential in-service dates (ISD) to consider in phasing project construction. GridLiance has evaluated a portfolio of transmission projects across a 2019-2027 study horizon to meet the identified needs in the Oklahoma Panhandle and East Central Oklahoma regions. The table below lists the potential mitigation options along with potential ISD.

2018 LPP Project Description Potential ISD Western Panhandle Voltage Support Retire Eva Regulator + Install 25-30 MVAR reactive support in Western 2020 Panhandle region12 Eastern Panhandle Voltage Support Add station and 25 MVAR reactive support at/near Turpin 2020 New approximately 7-mi 115 kV line from Ponderosa to Sunflower’s Liberal, 2022 new 115/69 kV station at Ponderosa New Source (TX-CO Outage) New approximately 23-mi 115kV line from Red Devil to SPS’ Hitchland 2022 New approximately 8.6-mi 115 kV line from Red Devil to Enel’s Goodwell 2022 Wind Install 14.4 MVAR reactive support at Powell Corner 2027 New approximately 18-mi 115 kV line from Dry Trails to a new 345/115 kV 2025 station tapping Walkemeyer-Hitchland 345 kV line Operational Needs Build new Y-Road Switching Station, 3-terminal ring bus 2019 Hovey To Thompson Overloads Rebuild Hovey to Thompson 69 kV lines 2027 New approximately 9-mi 115 kV line from Hovey to Texas County Interchange 2027 New approximately 23-mi 115kV line from Red Devil to SPS’ Hitchland 2022 New approximately 8.6-mi 115 kV line from Red Devil to Enel’s Goodwell 2022 Wind New approximately 25-mile 115 kV line from Dry Trails to new station tapping 2025 Liberal-Texas County Interchange 115 kV line near Hooker, OK New approximately 42-mile 115 kV line from Dry Trails to Sunflower’s Liberal 2025 New approximately 18-mi 115 kV line from Dry Trails to a new 345/115 kV 2025 station tapping Walkemeyer-Hitchland 345 kV line MW-Mile Dry Trails New approximately 25-mile 115 kV line from Dry Trails to new station tapping 2025 Liberal-Texas County Interchange 115 kV line near Hooker, OK New approximately 42-mile 115 kV line from Dry Trails to Sunflower’s Liberal 2025 New approximately 18-mi 115 kV line from Dry Trails to a new 345/115 kV 2025 station tapping Walkemeyer-Hitchland 345 kV line MW-Mile Rose New approximately 30-mile 115 kV line from Rose to Sunflower’s Liberal 2026

12 Determination of size and placement of reactive support will be performed in a separate EMTP study

April 1, 2019

New approximately 20-mile 115 kV line from Rose to OKGE’s Badger 345kV 2026 station, add 345/115 kV transformer MW-Mile Ahloso Close Egypt Switch after all necessary system modifications and relay 2019 coordination within and external to the GridLiance system takes place 13 Table 19: GridLiance 2018 LPP Project Options

Considering cost, mitigation effectiveness, and construction time, GridLiance has selected the following projects to mitigate issues identified in the 2018 LPP planning study:

Western Panhandle Voltage Support Cost ($M)14 Potential ISD Retire Eva Regulator + Install 25-30 MVAR reactive support in Western 4 2020 Panhandle region Eastern Panhandle Voltage Support Add station and 25 MVAR reactive support at/near Turpin 5 2020 New Source (TX-CO Outage) New approximately 8.6-mi 115 kV line from Red Devil to Enel’s TBD 2022 Goodwell Wind Install 14.4 MVAR reactive support at Powell Corner TBD 2027 Operational Needs Build new Y-Road Switching Station, 3-terminal ring bus 4.5 2019 MW-Mile Dry Trails New approximately 25-mile 115 kV line from Dry Trails to new station TBD 2024 tapping Liberal-Texas County Interchange 115 kV line near Hooker, OK MW-Mile Rose New approximately 30-mile 115 kV line from Rose to Sunflower’s Liberal TBD 2026

MW-Mile Ahloso Close Egypt Switch after all necessary system modifications and relay TBD 2019 coordination within and external to the GridLiance system takes place Table 20: GridLiance Selected 2018 LPP Mitigations

13 There are on-going interconnection discussions with other Transmission Owners for this project. Details on other equipment will be added upon execution of agreements. 14 These planning level cost estimates are subject to internal review and budgeting. Including the projects and the associated costs in this table does not indicate financial commitment.

April 1, 2019

APPENDIX A

Base Load -Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 523051 TC-EVAREG 2 69 BASE CASE 0.946 0.926 0.919 0.947 0.922 522900 GRIGGS-T 2 69 P1.2-Powell Corner-TX Co 115 kV 0.932 0.911 0.903 0.942 0.912 522901 TIE-NO 2 69 P1.2-Powell Corner-TX Co 115 kV 0.950 0.933 0.923 0.934 522902 GRIGGS 2 69 P1.2-Powell Corner-TX Co 115 kV 0.927 0.905 0.897 0.936 0.906 522904 LOBO 3 115 P1.2-Powell Corner-TX Co 115 kV 0.933 0.914 0.908 0.944 0.914 522905 STURGIS 2 69 P1.2-Powell Corner-TX Co 115 kV 0.933 0.911 0.904 0.941 0.911 522908 PIRATE 2 69 P1.2-Powell Corner-TX Co 115 kV 0.924 0.905 0.894 0.935 0.905 522909 FELT 2 69 P1.2-Powell Corner-TX Co 115 kV 0.907 0.886 0.875 0.918 0.887 522915 CLARK-T 2 69 P1.2-Powell Corner-TX Co 115 kV 0.925 0.906 0.895 0.936 0.906 522919 COUGAR 2 69 P1.2-Powell Corner-TX Co 115 kV 0.912 0.891 0.880 0.922 0.892 522920 ELMS_TAP 2 69 P1.2-Powell Corner-TX Co 115 kV 0.912 0.892 0.881 0.923 0.892 522921 THRASH 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.919 0.912 0.949 0.919 522925 DOOLIN 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.919 0.912 0.949 0.919 522929 POWELL CNR 2 69 P1.2-Powell Corner-TX Co 115 kV 0.946 0.922 0.916 0.923 522932 MARTINEZ 2 69 P1.2-Powell Corner-TX Co 115 kV 0.937 0.921 0.909 0.949 0.921 522937 BLADE 2 69 P1.2-Powell Corner-TX Co 115 kV 0.924 0.905 0.894 0.935 0.905 522940 WILDCAT 2 69 P1.2-Powell Corner-TX Co 115 kV 0.912 0.891 0.880 0.922 0.892 522941 LOBO-T 3 115 P1.2-Powell Corner-TX Co 115 kV 0.933 0.914 0.908 0.944 0.914 522944 STURGIS-T 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.919 0.912 0.949 0.919 522948 PANHANDLE 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.919 0.912 0.949 0.920 522949 ELMS 2 69 P1.2-Powell Corner-TX Co 115 kV 0.912 0.892 0.881 0.923 0.892 522950 THRALL 2 69 P1.2-Powell Corner-TX Co 115 kV 0.938 0.914 0.907 0.944 0.914 522954 HOVEY 3 115 P1.2-Powell Corner-TX Co 115 kV 0.933 0.928 0.934 522957 POWELL CNR 3 115 P1.2-Powell Corner-TX Co 115 kV 0.942 0.923 0.917 0.924 522960 PANHANDLE 3 115 P1.2-Powell Corner-TX Co 115 kV 0.941 0.921 0.914 0.921 523006 TC-ELKHART 2 69 P1.2-Powell Corner-TX Co 115 kV 0.937 0.921 0.909 0.949 0.921 523044 TC-ELKHRT_T2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.930 0.941 523099 TC-DRYTRLS 3 115 P1.2-Powell Corner-TX Co 115 kV 0.928 0.909 0.903 0.939 0.909 522908 PIRATE 2 69 P1.2-HOVEY-BLADE 69 KV 0.910 0.891 0.877 0.904 0.884 522909 FELT 2 69 P1.2-HOVEY-BLADE 69 KV 0.919 0.902 0.888 0.914 0.894 522919 COUGAR 2 69 P1.2-HOVEY-BLADE 69 KV 0.924 0.907 0.893 0.919 0.900 522920 ELMS_TAP 2 69 P1.2-HOVEY-BLADE 69 KV 0.920 0.902 0.889 0.915 0.895 522937 BLADE 2 69 P1.2-HOVEY-BLADE 69 KV 0.910 0.891 0.877 0.904 0.884 522940 WILDCAT 2 69 P1.2-HOVEY-BLADE 69 KV 0.924 0.907 0.893 0.919 0.900 522949 ELMS 2 69 P1.2-HOVEY-BLADE 69 KV 0.920 0.902 0.889 0.915 0.895 522898 BEARD-T 2 69 P2.2-COLE-115KV BUS 0.823 0.793 0.763 0.823 0.792 522903 ELMWOOD 2 69 P2.2-COLE-115KV BUS 0.757 0.721 0.682 0.755 0.719 522908 PIRATE 2 69 P2.2-COLE-115KV BUS 0.945 0.927 0.943 522909 FELT 2 69 P2.2-COLE-115KV BUS 0.947 0.931 0.913 0.941 0.929 522910 ADAMS 2 69 P2.2-COLE-115KV BUS 0.833 0.803 0.775 0.832 0.802 522911 BALKO 2 69 P2.2-COLE-115KV BUS 0.763 0.727 0.690 0.762 0.726 522915 CLARK-T 2 69 P2.2-COLE-115KV BUS 0.946 0.928 0.944 522916 ELMWOOD-T 2 69 P2.2-COLE-115KV BUS 0.757 0.721 0.682 0.755 0.719 522917 ADAMS-T 2 69 P2.2-COLE-115KV BUS 0.835 0.806 0.778 0.835 0.805 522918 COLE 2 69 P2.2-COLE-115KV BUS 0.781 0.747 0.711 0.780 0.745 522919 COUGAR 2 69 P2.2-COLE-115KV BUS 0.936 0.918 0.946 0.933 522920 ELMS_TAP 2 69 P2.2-COLE-115KV BUS 0.936 0.918 0.946 0.933 522923 TURPIN 2 69 P2.2-COLE-115KV BUS 0.794 0.761 0.728 0.793 0.760 522927 JEFFERSON 2 69 P2.2-COLE-115KV BUS 0.867 0.840 0.816 0.866 0.839 522934 TURPIN-T 2 69 P2.2-COLE-115KV BUS 0.795 0.763 0.729 0.794 0.761 522937 BLADE 2 69 P2.2-COLE-115KV BUS 0.945 0.927 0.943 522940 WILDCAT 2 69 P2.2-COLE-115KV BUS 0.936 0.918 0.946 0.933 522943 BEARD 2 69 P2.2-COLE-115KV BUS 0.821 0.791 0.761 0.821 0.790 522946 HARDESTY 2 69 P2.2-COLE-115KV BUS 0.771 0.736 0.699 0.770 0.735 522947 HASKELL 2 69 P2.2-COLE-115KV BUS 0.759 0.723 0.684 0.757 0.720 522949 ELMS 2 69 P2.2-COLE-115KV BUS 0.936 0.918 0.946 0.933 522953 PONDEROSA 2 69 P2.2-COLE-115KV BUS 0.792 0.759 0.725 0.791 0.757 523018 TC-HOOKER 2 69 P2.2-COLE-115KV BUS 0.867 0.840 0.816 0.866 0.839

Table A1: Oklahoma Panhandle- Base Load- Voltage Violations

April 1, 2019

Base Load -Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522898 BEARD-T 2 69 P2.2-COLE-69KV BUS 0.912 0.893 0.882 0.916 0.889 522910 ADAMS 2 69 P2.2-COLE-69KV BUS 0.916 0.897 0.886 0.919 0.894 522917 ADAMS-T 2 69 P2.2-COLE-69KV BUS 0.918 0.899 0.889 0.922 0.896 522923 TURPIN 2 69 P2.2-COLE-69KV BUS 0.900 0.880 0.868 0.904 0.877 522927 JEFFERSON 2 69 P2.2-COLE-69KV BUS 0.935 0.917 0.907 0.938 0.914 522934 TURPIN-T 2 69 P2.2-COLE-69KV BUS 0.901 0.880 0.869 0.904 0.877 522943 BEARD 2 69 P2.2-COLE-69KV BUS 0.910 0.891 0.880 0.914 0.887 522953 PONDEROSA 2 69 P2.2-COLE-69KV BUS 0.897 0.877 0.865 0.901 0.874 523018 TC-HOOKER 2 69 P2.2-COLE-69KV BUS 0.935 0.917 0.907 0.938 0.914 522898 BEARD-T 2 69 P7-COLE-SUB 0.905 0.884 0.871 0.903 0.882 522910 ADAMS 2 69 P7-COLE-SUB 0.908 0.889 0.876 0.907 0.887 522917 ADAMS-T 2 69 P7-COLE-SUB 0.911 0.891 0.878 0.909 0.889 522923 TURPIN 2 69 P7-COLE-SUB 0.892 0.872 0.857 0.891 0.870 522927 JEFFERSON 2 69 P7-COLE-SUB 0.928 0.909 0.897 0.926 0.907 522934 TURPIN-T 2 69 P7-COLE-SUB 0.893 0.872 0.858 0.891 0.870 522943 BEARD 2 69 P7-COLE-SUB 0.903 0.882 0.869 0.901 0.880 522953 PONDEROSA 2 69 P7-COLE-SUB 0.890 0.869 0.854 0.888 0.867 523018 TC-HOOKER 2 69 P7-COLE-SUB 0.928 0.909 0.897 0.926 0.907 522901 TIE-NO 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.948 0.930 0.944 522908 PIRATE 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.918 0.904 0.882 0.923 0.900 522909 FELT 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.886 0.871 0.846 0.891 0.867 522915 CLARK-T 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.920 0.906 0.884 0.924 0.902 522919 COUGAR 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.891 0.876 0.851 0.896 0.872 522920 ELMS_TAP 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.894 0.879 0.855 0.899 0.875 522932 MARTINEZ 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.940 0.921 0.936 522937 BLADE 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.918 0.904 0.882 0.923 0.900 522940 WILDCAT 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.891 0.876 0.851 0.896 0.872 522949 ELMS 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.894 0.879 0.855 0.899 0.875 523006 TC-ELKHART 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.940 0.921 0.936 522909 FELT 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.941 0.927 0.945 0.933 522908 PIRATE 2 69 P2.2-HOVEY-69KV BUS 0.900 0.884 0.867 0.892 0.874 522909 FELT 2 69 P2.2-HOVEY-69KV BUS 0.910 0.894 0.877 0.902 0.884 522919 COUGAR 2 69 P2.2-HOVEY-69KV BUS 0.914 0.899 0.883 0.906 0.889 522920 ELMS_TAP 2 69 P2.2-HOVEY-69KV BUS 0.910 0.895 0.878 0.902 0.885 522937 BLADE 2 69 P2.2-HOVEY-69KV BUS 0.900 0.884 0.867 0.892 0.874 522940 WILDCAT 2 69 P2.2-HOVEY-69KV BUS 0.914 0.899 0.883 0.906 0.889 522949 ELMS 2 69 P2.2-HOVEY-69KV BUS 0.910 0.878 0.902 0.885 522908 PIRATE 2 69 P7-HOVEY-SUB 0.899 0.882 0.867 0.890 0.873 522909 FELT 2 69 P7-HOVEY-SUB 0.908 0.892 0.877 0.900 0.883 522919 COUGAR 2 69 P7-HOVEY-SUB 0.913 0.897 0.883 0.905 0.888 522920 ELMS_TAP 2 69 P7-HOVEY-SUB 0.909 0.893 0.878 0.901 0.884 522937 BLADE 2 69 P7-HOVEY-SUB 0.899 0.882 0.867 0.890 0.873 522940 WILDCAT 2 69 P7-HOVEY-SUB 0.913 0.897 0.883 0.905 0.888 522949 ELMS 2 69 P7-HOVEY-SUB 0.909 0.893 0.878 0.901 0.884 522898 BEARD-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.834 0.840 522903 ELMWOOD 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.769 0.774 522910 ADAMS 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.844 0.849 522911 BALKO 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.775 0.781 522916 ELMWOOD-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.769 0.774 522917 ADAMS-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.846 0.851 522918 COLE 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.793 0.798 522923 TURPIN 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.806 0.811 522927 JEFFERSON 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.877 0.882 522934 TURPIN-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.807 0.812 522943 BEARD 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.832 0.838 522946 HARDESTY 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.783 0.789 522947 HASKELL 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.771 0.776 522953 PONDEROSA 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.803 0.809 523018 TC-HOOKER 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.877 0.882

Table A1: Oklahoma Panhandle- Base Load- Voltage Violations (cont.)

April 1, 2019

Base Load -Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522898 BEARD-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.939 0.936 0.927 0.944 0.934 522900 GRIGGS-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.925 0.913 0.899 0.923 0.910 522901 TIE-NO 2 69 P2.2-TXCOUNTY-69KV BUS 0.911 0.903 0.884 0.911 0.899 522902 GRIGGS 2 69 P2.2-TXCOUNTY-69KV BUS 0.920 0.907 0.892 0.917 0.904 522904 LOBO 3 115 P2.2-TXCOUNTY-69KV BUS 0.929 0.919 0.907 0.928 0.916 522905 STURGIS 2 69 P2.2-TXCOUNTY-69KV BUS 0.930 0.917 0.903 0.926 0.914 522907 BOAR 2 69 P2.2-TXCOUNTY-69KV BUS 0.903 0.890 0.878 0.903 0.888 522908 PIRATE 2 69 P2.2-TXCOUNTY-69KV BUS 0.893 0.883 0.863 0.892 0.879 522909 FELT 2 69 P2.2-TXCOUNTY-69KV BUS 0.885 0.872 0.853 0.883 0.869 522910 ADAMS 2 69 P2.2-TXCOUNTY-69KV BUS 0.932 0.927 0.918 0.937 0.925 522915 CLARK-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.894 0.884 0.864 0.893 0.880 522917 ADAMS-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.934 0.929 0.920 0.939 0.927 522919 COUGAR 2 69 P2.2-TXCOUNTY-69KV BUS 0.890 0.878 0.859 0.888 0.874 522920 ELMS_TAP 2 69 P2.2-TXCOUNTY-69KV BUS 0.889 0.877 0.857 0.887 0.873 522921 THRASH 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.925 0.912 0.935 0.923 522922 EVA-W 2 69 P2.2-TXCOUNTY-69KV BUS 0.917 0.909 0.890 0.916 0.906 522925 DOOLIN 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.925 0.912 0.935 0.923 522927 JEFFERSON 2 69 P2.2-TXCOUNTY-69KV BUS 0.923 0.916 0.906 0.927 0.914 522928 OPTIMA 2 69 P2.2-TXCOUNTY-69KV BUS 0.912 0.899 0.887 0.912 0.897 522929 POWELL CNR 2 69 P2.2-TXCOUNTY-69KV BUS 0.943 0.928 0.916 0.937 0.926 522932 MARTINEZ 2 69 P2.2-TXCOUNTY-69KV BUS 0.896 0.887 0.867 0.895 0.884 522937 BLADE 2 69 P2.2-TXCOUNTY-69KV BUS 0.893 0.883 0.863 0.892 0.879 522940 WILDCAT 2 69 P2.2-TXCOUNTY-69KV BUS 0.890 0.878 0.859 0.888 0.874 522941 LOBO-T 3 115 P2.2-TXCOUNTY-69KV BUS 0.929 0.919 0.907 0.928 0.916 522943 BEARD 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.934 0.925 0.943 0.932 522944 STURGIS-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.924 0.912 0.934 0.922 522948 PANHANDLE 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.926 0.913 0.935 0.923 522949 ELMS 2 69 P2.2-TXCOUNTY-69KV BUS 0.889 0.877 0.857 0.887 0.873 522950 THRALL 2 69 P2.2-TXCOUNTY-69KV BUS 0.934 0.920 0.907 0.929 0.917 522954 HOVEY 3 115 P2.2-TXCOUNTY-69KV BUS 0.927 0.917 0.905 0.927 0.914 522957 POWELL CNR 3 115 P2.2-TXCOUNTY-69KV BUS 0.938 0.928 0.916 0.937 0.925 522960 PANHANDLE 3 115 P2.2-TXCOUNTY-69KV BUS 0.937 0.926 0.914 0.935 0.923 523001 TC-HOVEY 2 69 P2.2-TXCOUNTY-69KV BUS 0.915 0.903 0.891 0.916 0.901 523006 TC-ELKHART 2 69 P2.2-TXCOUNTY-69KV BUS 0.896 0.887 0.867 0.895 0.884 523018 TC-HOOKER 2 69 P2.2-TXCOUNTY-69KV BUS 0.923 0.916 0.906 0.927 0.914 523044 TC-ELKHRT_T2 69 P2.2-TXCOUNTY-69KV BUS 0.916 0.908 0.889 0.915 0.904 523051 TC-EVAREG 2 69 P2.2-TXCOUNTY-69KV BUS 0.849 0.831 0.814 0.849 0.828 523065 TC-THOMPSON2 69 P2.2-TXCOUNTY-69KV BUS 0.905 0.892 0.880 0.905 0.890 523066 TUCKER 2 69 P2.2-TXCOUNTY-69KV BUS 0.905 0.892 0.880 0.905 0.890 523072 TC-SEABOARD2 69 P2.2-TXCOUNTY-69KV BUS 0.903 0.890 0.878 0.903 0.888 523099 TC-DRYTRLS 3 115 P2.2-TXCOUNTY-69KV BUS 0.924 0.914 0.902 0.923 0.911 522898 BEARD-T 2 69 P7-HITCHLAND-115KV-SUB 0.903 0.893 0.884 0.900 0.895 522900 GRIGGS-T 2 69 P7-HITCHLAND-115KV-SUB 0.863 0.841 0.822 0.859 0.843 522901 TIE-NO 2 69 P7-HITCHLAND-115KV-SUB 0.861 0.840 0.819 0.861 0.844 522902 GRIGGS 2 69 P7-HITCHLAND-115KV-SUB 0.857 0.835 0.815 0.852 0.836 522903 ELMWOOD 2 69 P7-HITCHLAND-115KV-SUB 0.934 0.933 0.929 0.929 0.934 522904 LOBO 3 115 P7-HITCHLAND-115KV-SUB 0.867 0.848 0.832 0.864 0.849 522905 STURGIS 2 69 P7-HITCHLAND-115KV-SUB 0.867 0.844 0.826 0.861 0.846 522907 BOAR 2 69 P7-HITCHLAND-115KV-SUB 0.894 0.873 0.861 0.897 0.877 522908 PIRATE 2 69 P7-HITCHLAND-115KV-SUB 0.838 0.815 0.792 0.836 0.819 522909 FELT 2 69 P7-HITCHLAND-115KV-SUB 0.825 0.801 0.777 0.822 0.804 522910 ADAMS 2 69 P7-HITCHLAND-115KV-SUB 0.895 0.884 0.874 0.893 0.886 522911 BALKO 2 69 P7-HITCHLAND-115KV-SUB 0.939 0.938 0.935 0.934 0.939 522912 Y ROAD 3 115 P7-HITCHLAND-115KV-SUB 0.888 0.871 0.855 0.884 0.871 522915 CLARK-T 2 69 P7-HITCHLAND-115KV-SUB 0.839 0.816 0.793 0.838 0.820 522916 ELMWOOD-T 2 69 P7-HITCHLAND-115KV-SUB 0.934 0.933 0.929 0.929 0.934 522917 ADAMS-T 2 69 P7-HITCHLAND-115KV-SUB 0.898 0.886 0.877 0.895 0.888 522919 COUGAR 2 69 P7-HITCHLAND-115KV-SUB 0.831 0.807 0.784 0.828 0.810 522920 ELMS_TAP 2 69 P7-HITCHLAND-115KV-SUB 0.830 0.806 0.783 0.828 0.809

Table A1: Oklahoma Panhandle- Base Load- Voltage Violations (cont.)

April 1, 2019

Base Load -Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522921 THRASH 2 69 P7-HITCHLAND-115KV-SUB 0.874 0.853 0.836 0.869 0.854 522922 EVA-W 2 69 P7-HITCHLAND-115KV-SUB 0.869 0.848 0.827 0.868 0.852 522923 TURPIN 2 69 P7-HITCHLAND-115KV-SUB 0.926 0.921 0.913 0.922 0.922 522925 DOOLIN 2 69 P7-HITCHLAND-115KV-SUB 0.874 0.853 0.836 0.869 0.854 522926 BOURK 2 69 P7-HITCHLAND-115KV-SUB 0.909 0.887 0.876 0.912 0.892 522927 JEFFERSON 2 69 P7-HITCHLAND-115KV-SUB 0.888 0.874 0.863 0.887 0.876 522928 OPTIMA 2 69 P7-HITCHLAND-115KV-SUB 0.880 0.859 0.846 0.881 0.862 522929 POWELL CNR 2 69 P7-HITCHLAND-115KV-SUB 0.881 0.858 0.841 0.873 0.859 522930 RED DEVIL 3 115 P7-HITCHLAND-115KV-SUB 0.886 0.869 0.852 0.881 0.869 522931 REED 2 69 P7-HITCHLAND-115KV-SUB 0.909 0.887 0.876 0.912 0.892 522932 MARTINEZ 2 69 P7-HITCHLAND-115KV-SUB 0.846 0.824 0.801 0.846 0.828 522934 TURPIN-T 2 69 P7-HITCHLAND-115KV-SUB 0.925 0.920 0.912 0.921 0.921 522935 GOODWELL 3 115 P7-HITCHLAND-115KV-SUB 0.887 0.870 0.853 0.882 0.870 522937 BLADE 2 69 P7-HITCHLAND-115KV-SUB 0.838 0.815 0.792 0.836 0.819 522940 WILDCAT 2 69 P7-HITCHLAND-115KV-SUB 0.831 0.807 0.784 0.828 0.810 522941 LOBO-T 3 115 P7-HITCHLAND-115KV-SUB 0.867 0.848 0.832 0.864 0.849 522943 BEARD 2 69 P7-HITCHLAND-115KV-SUB 0.901 0.891 0.881 0.898 0.893 522944 STURGIS-T 2 69 P7-HITCHLAND-115KV-SUB 0.874 0.853 0.835 0.869 0.854 522947 HASKELL 2 69 P7-HITCHLAND-115KV-SUB 0.935 0.934 0.931 0.930 0.935 522948 PANHANDLE 2 69 P7-HITCHLAND-115KV-SUB 0.874 0.853 0.836 0.870 0.855 522949 ELMS 2 69 P7-HITCHLAND-115KV-SUB 0.830 0.806 0.783 0.828 0.809 522950 THRALL 2 69 P7-HITCHLAND-115KV-SUB 0.872 0.848 0.831 0.864 0.849 522953 PONDEROSA 2 69 P7-HITCHLAND-115KV-SUB 0.922 0.916 0.908 0.918 0.918 522954 HOVEY 3 115 P7-HITCHLAND-115KV-SUB 0.880 0.860 0.845 0.878 0.862 522957 POWELL CNR 3 115 P7-HITCHLAND-115KV-SUB 0.877 0.858 0.842 0.874 0.859 522960 PANHANDLE 3 115 P7-HITCHLAND-115KV-SUB 0.875 0.855 0.838 0.871 0.856 523001 TC-HOVEY 2 69 P7-HITCHLAND-115KV-SUB 0.884 0.863 0.850 0.885 0.866 523006 TC-ELKHART 2 69 P7-HITCHLAND-115KV-SUB 0.846 0.824 0.801 0.846 0.828 523018 TC-HOOKER 2 69 P7-HITCHLAND-115KV-SUB 0.888 0.874 0.863 0.887 0.876 523044 TC-ELKHRT_T2 69 P7-HITCHLAND-115KV-SUB 0.867 0.846 0.825 0.866 0.850 523051 TC-EVAREG 2 69 P7-HITCHLAND-115KV-SUB 0.804 0.775 0.755 0.803 0.778 523065 TC-THOMPSON2 69 P7-HITCHLAND-115KV-SUB 0.893 0.871 0.859 0.895 0.875 523066 TUCKER 2 69 P7-HITCHLAND-115KV-SUB 0.893 0.871 0.859 0.895 0.875 523072 TC-SEABOARD2 69 P7-HITCHLAND-115KV-SUB 0.894 0.873 0.861 0.897 0.877 523089 TC-TXCOUNTY2 69 P7-HITCHLAND-115KV-SUB 0.909 0.887 0.876 0.912 0.892 523099 TC-DRYTRLS 3 115 P7-HITCHLAND-115KV-SUB 0.862 0.843 0.826 0.859 0.844 523113 TC-MCMURRY 3 115 P7-HITCHLAND-115KV-SUB 0.910 0.895 0.882 0.904 0.895 523090 TEXAS_CNTY 3 115 P7-HITCHLAND-115KV-SUB 0.907 0.890 0.874 0.899 0.889 523106 TXPHSF 3 115 P7-HITCHLAND-115KV-SUB 0.905 0.889 0.863 0.896 0.886

Table A1: Oklahoma Panhandle- Base Load- Voltage Violations (cont.)

April 1, 2019

Summer High Load-Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 523051 TC-EVAREG 2 69 Base Case 0.945 0.911 0.902 0.929 0.908 522909 FELT 2 69 Base Case 0.948 0.936 0.944 522919 COUGAR 2 69 Base Case 0.942 0.949 522920 ELMS_TAP 2 69 Base Case 0.942 0.949 522940 WILDCAT 2 69 Base Case 0.942 0.949 522949 ELMS 2 69 Base Case 0.942 0.949 522900 GRIGGS-T 2 69 P1.2-Powell Corner-TX Co 115 kV 0.932 0.887 0.876 0.924 0.889 522901 TIE-NO 2 69 P1.2-Powell Corner-TX Co 115 kV 0.949 0.903 0.889 0.944 0.906 522902 GRIGGS 2 69 P1.2-Powell Corner-TX Co 115 kV 0.926 0.880 0.869 0.917 0.883 522904 LOBO 3 115 P1.2-Powell Corner-TX Co 115 kV 0.932 0.894 0.885 0.928 0.896 522905 STURGIS 2 69 P1.2-Powell Corner-TX Co 115 kV 0.933 0.888 0.878 0.924 0.890 522908 PIRATE 2 69 P1.2-Powell Corner-TX Co 115 kV 0.923 0.873 0.858 0.914 0.876 522909 FELT 2 69 P1.2-Powell Corner-TX Co 115 kV 0.907 0.883 0.838 0.896 0.856 522915 CLARK-T 2 69 P1.2-Powell Corner-TX Co 115 kV 0.924 0.874 0.859 0.916 0.877 522919 COUGAR 2 69 P1.2-Powell Corner-TX Co 115 kV 0.911 0.860 0.845 0.901 0.862 522920 ELMS_TAP 2 69 P1.2-Powell Corner-TX Co 115 kV 0.912 0.860 0.845 0.901 0.863 522921 THRASH 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.897 0.887 0.932 0.899 522922 EVA-W 2 69 P1.2-Powell Corner-TX Co 115 kV 0.913 0.899 0.915 522925 DOOLIN 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.897 0.887 0.932 0.899 522927 JEFFERSON 2 69 P1.2-Powell Corner-TX Co 115 kV 0.935 0.928 0.935 522928 OPTIMA 2 69 P1.2-Powell Corner-TX Co 115 kV 0.929 0.923 0.932 522929 POWELL CNR 2 69 P1.2-Powell Corner-TX Co 115 kV 0.946 0.902 0.893 0.936 0.904 522932 MARTINEZ 2 69 P1.2-Powell Corner-TX Co 115 kV 0.937 0.888 0.873 0.930 0.891 522937 BLADE 2 69 P1.2-Powell Corner-TX Co 115 kV 0.923 0.873 0.858 0.914 0.876 522940 WILDCAT 2 69 P1.2-Powell Corner-TX Co 115 kV 0.911 0.860 0.845 0.901 0.862 522941 LOBO-T 3 115 P1.2-Powell Corner-TX Co 115 kV 0.932 0.894 0.885 0.928 0.896 522944 STURGIS-T 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.897 0.887 0.932 0.899 522948 PANHANDLE 2 69 P1.2-Powell Corner-TX Co 115 kV 0.940 0.897 0.887 0.932 0.900 522949 ELMS 2 69 P1.2-Powell Corner-TX Co 115 kV 0.912 0.860 0.845 0.901 0.863 522950 THRALL 2 69 P1.2-Powell Corner-TX Co 115 kV 0.937 0.892 0.882 0.927 0.894 522954 HOVEY 3 115 P1.2-Powell Corner-TX Co 115 kV 0.915 0.907 0.948 0.917 522957 POWELL CNR 3 115 P1.2-Powell Corner-TX Co 115 kV 0.941 0.903 0.895 0.937 0.906 522960 PANHANDLE 3 115 P1.2-Powell Corner-TX Co 115 kV 0.940 0.900 0.890 0.934 0.902 523001 TC-HOVEY 2 69 P1.2-Powell Corner-TX Co 115 kV 0.933 0.927 0.935 523006 TC-ELKHART 2 69 P1.2-Powell Corner-TX Co 115 kV 0.937 0.888 0.873 0.930 0.891 523018 TC-HOOKER 2 69 P1.2-Powell Corner-TX Co 115 kV 0.935 0.928 0.935 523044 TC-ELKHRT_T2 69 P1.2-Powell Corner-TX Co 115 kV 0.911 0.897 0.913 523099 TC-DRYTRLS 3 115 P1.2-Powell Corner-TX Co 115 kV 0.928 0.889 0.880 0.923 0.891 522908 PIRATE 2 69 P1.2-HOVEY-BLADE 69 KV 0.909 0.867 0.850 0.882 0.861 522909 FELT 2 69 P1.2-HOVEY-BLADE 69 KV 0.919 0.898 0.862 0.893 0.872 522919 COUGAR 2 69 P1.2-HOVEY-BLADE 69 KV 0.924 0.884 0.869 0.899 0.878 522920 ELMS_TAP 2 69 P1.2-HOVEY-BLADE 69 KV 0.920 0.880 0.864 0.894 0.874 522937 BLADE 2 69 P1.2-HOVEY-BLADE 69 KV 0.909 0.867 0.850 0.882 0.861 522940 WILDCAT 2 69 P1.2-HOVEY-BLADE 69 KV 0.924 0.884 0.869 0.899 0.878 522949 ELMS 2 69 P1.2-HOVEY-BLADE 69 KV 0.920 0.880 0.864 0.894 0.873 522898 BEARD-T 2 69 P2.2-COLE-115KV BUS 0.774 0.737 0.705 0.776 0.739 522900 GRIGGS-T 2 69 P2.2-COLE-115KV BUS 0.940 0.927 0.939 522901 TIE-NO 2 69 P2.2-COLE-115KV BUS 0.940 0.923 0.941 522902 GRIGGS 2 69 P2.2-COLE-115KV BUS 0.933 0.920 0.948 0.933 522903 ELMWOOD 2 69 P2.2-COLE-115KV BUS 0.692 0.647 0.605 0.693 0.648 522908 PIRATE 2 69 P2.2-COLE-115KV BUS 0.940 0.915 0.898 0.937 0.916 522909 FELT 2 69 P2.2-COLE-115KV BUS 0.925 0.901 0.880 0.922 0.902 522910 ADAMS 2 69 P2.2-COLE-115KV BUS 0.786 0.750 0.720 0.788 0.752 522911 BALKO 2 69 P2.2-COLE-115KV BUS 0.700 0.655 0.614 0.701 0.657 522915 CLARK-T 2 69 P2.2-COLE-115KV BUS 0.941 0.916 0.899 0.938 0.917 522916 ELMWOOD-T 2 69 P2.2-COLE-115KV BUS 0.692 0.647 0.605 0.693 0.648 522917 ADAMS-T 2 69 P2.2-COLE-115KV BUS 0.789 0.753 0.723 0.791 0.755 522918 COLE 2 69 P2.2-COLE-115KV BUS 0.722 0.679 0.640 0.723 0.680 522919 COUGAR 2 69 P2.2-COLE-115KV BUS 0.931 0.907 0.886 0.927 0.907 522920 ELMS_TAP 2 69 P2.2-COLE-115KV BUS 0.930 0.907 0.884 0.927 0.907 522922 EVA-W 2 69 P2.2-COLE-115KV BUS 0.947 0.926 0.948

Table A2: Oklahoma Panhandle- Summer High Load Voltage Violations

April 1, 2019

Summer High Load-Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522923 TURPIN 2 69 P2.2-COLE-115KV BUS 0.739 0.698 0.662 0.740 0.700 522927 JEFFERSON 2 69 P2.2-COLE-115KV BUS 0.827 0.794 0.769 0.828 0.797 522932 MARTINEZ 2 69 P2.2-COLE-115KV BUS 0.949 0.924 0.906 0.948 0.925 522934 TURPIN-T 2 69 P2.2-COLE-115KV BUS 0.740 0.699 0.663 0.741 0.701 522937 BLADE 2 69 P2.2-COLE-115KV BUS 0.940 0.915 0.898 0.937 0.916 522943 BEARD 2 69 P2.2-COLE-115KV BUS 0.772 0.734 0.702 0.773 0.736 522946 HARDESTY 2 69 P2.2-COLE-115KV BUS 0.710 0.666 0.626 0.711 0.668 522947 HASKELL 2 69 P2.2-COLE-115KV BUS 0.694 0.649 0.608 0.696 0.651 522949 ELMS 2 69 P2.2-COLE-115KV BUS 0.930 0.907 0.885 0.927 0.907 522953 PONDEROSA 2 69 P2.2-COLE-115KV BUS 0.736 0.695 0.658 0.737 0.696 523006 TC-ELKHART 2 69 P2.2-COLE-115KV BUS 0.949 0.924 0.906 0.948 0.925 523018 TC-HOOKER 2 69 P2.2-COLE-115KV BUS 0.827 0.794 0.769 0.828 0.797 523044 TC-ELKHRT_T2 69 P2.2-COLE-115KV BUS 0.945 0.929 0.946 523099 TC-DRYTRLS 3 115 P2.2-COLE-115KV BUS 0.941 0.926 0.940 522898 BEARD-T 2 69 P2.2-COLE-69KV BUS 0.890 0.869 0.856 0.895 0.868 522910 ADAMS 2 69 P2.2-COLE-69KV BUS 0.895 0.874 0.862 0.899 0.873 522917 ADAMS-T 2 69 P2.2-COLE-69KV BUS 0.897 0.877 0.864 0.902 0.875 522923 TURPIN 2 69 P2.2-COLE-69KV BUS 0.877 0.855 0.841 0.881 0.853 522927 JEFFERSON 2 69 P2.2-COLE-69KV BUS 0.916 0.897 0.885 0.920 0.895 522934 TURPIN-T 2 69 P2.2-COLE-69KV BUS 0.877 0.855 0.841 0.882 0.854 522943 BEARD 2 69 P2.2-COLE-69KV BUS 0.888 0.867 0.854 0.893 0.865 522953 PONDEROSA 2 69 P2.2-COLE-69KV BUS 0.873 0.852 0.837 0.878 0.850 523018 TC-HOOKER 2 69 P2.2-COLE-69KV BUS 0.916 0.897 0.885 0.920 0.895 522898 BEARD-T 2 69 P7-COLE-SUB 0.882 0.860 0.844 0.881 0.860 522908 PIRATE 2 69 P7-COLE-SUB 0.941 0.925 0.939 522910 ADAMS 2 69 P7-COLE-SUB 0.886 0.865 0.850 0.886 0.865 522915 CLARK-T 2 69 P7-COLE-SUB 0.942 0.926 0.940 522917 ADAMS-T 2 69 P7-COLE-SUB 0.889 0.868 0.852 0.888 0.867 522923 TURPIN 2 69 P7-COLE-SUB 0.868 0.846 0.828 0.867 0.845 522927 JEFFERSON 2 69 P7-COLE-SUB 0.908 0.888 0.874 0.907 0.887 522934 TURPIN-T 2 69 P7-COLE-SUB 0.868 0.846 0.829 0.868 0.845 522937 BLADE 2 69 P7-COLE-SUB 0.941 0.925 0.939 522943 BEARD 2 69 P7-COLE-SUB 0.879 0.858 0.842 0.879 0.857 522953 PONDEROSA 2 69 P7-COLE-SUB 0.865 0.842 0.825 0.864 0.842 523018 TC-HOOKER 2 69 P7-COLE-SUB 0.908 0.888 0.874 0.907 0.887 522901 TIE-NO 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.905 0.878 0.943 0.903 522908 PIRATE 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.917 0.853 0.819 0.895 0.850 522909 FELT 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.886 0.851 0.775 0.858 0.810 522915 CLARK-T 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.919 0.855 0.822 0.897 0.853 522919 COUGAR 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.891 0.820 0.783 0.864 0.817 522920 ELMS_TAP 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.894 0.823 0.786 0.867 0.820 522922 EVA-W 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.921 0.895 0.919 522932 MARTINEZ 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.896 0.868 0.934 0.894 522937 BLADE 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.917 0.853 0.819 0.895 0.850 522940 WILDCAT 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.891 0.820 0.783 0.864 0.817 522949 ELMS 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.894 0.823 0.786 0.867 0.820 523006 TC-ELKHART 2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.896 0.868 0.934 0.894 523044 TC-ELKHRT_T2 69 P1.2-COUGAR-PANHANDLE 69 KV 0.919 0.892 0.916 522908 PIRATE 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.932 0.916 0.943 0.925 522915 CLARK-T 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.933 0.917 0.944 0.926 522919 COUGAR 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.925 0.908 0.934 0.917 522920 ELMS_TAP 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.924 0.908 0.934 0.917 522932 MARTINEZ 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.940 0.923 0.933 522937 BLADE 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.932 0.916 0.943 0.925 522940 WILDCAT 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.925 0.908 0.934 0.918 522949 ELMS 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.924 0.908 0.934 0.917 523006 TC-ELKHART 2 69 P7-DBL CKT-69kVHOVEY-THOMPSON 0.940 0.923 0.933 522908 PIRATE 2 69 P2.2-HOVEY-69KV BUS 0.877 0.859 0.839 0.867 0.850 522909 FELT 2 69 P2.2-HOVEY-69KV BUS 0.888 0.870 0.851 0.878 0.861 522919 COUGAR 2 69 P2.2-HOVEY-69KV BUS 0.893 0.876 0.857 0.883 0.867 522920 ELMS_TAP 2 69 P2.2-HOVEY-69KV BUS 0.889 0.871 0.852 0.879 0.863 522937 BLADE 2 69 P2.2-HOVEY-69KV BUS 0.877 0.859 0.839 0.867 0.850 522940 WILDCAT 2 69 P2.2-HOVEY-69KV BUS 0.893 0.876 0.857 0.883 0.867 522949 ELMS 2 69 P2.2-HOVEY-69KV BUS 0.889 0.871 0.852 0.879 0.863

Table A2: Oklahoma Panhandle- Summer High Load Voltage Violations (cont.)

April 1, 2019

Summer High Load-Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522908 PIRATE 2 69 P7-HOVEY-SUB 0.875 0.857 0.837 0.865 0.848 522909 FELT 2 69 P7-HOVEY-SUB 0.886 0.868 0.849 0.876 0.860 522919 COUGAR 2 69 P7-HOVEY-SUB 0.892 0.874 0.856 0.882 0.866 522920 ELMS_TAP 2 69 P7-HOVEY-SUB 0.887 0.870 0.850 0.877 0.861 522937 BLADE 2 69 P7-HOVEY-SUB 0.875 0.857 0.837 0.865 0.848 522940 WILDCAT 2 69 P7-HOVEY-SUB 0.892 0.874 0.856 0.882 0.866 522949 ELMS 2 69 P7-HOVEY-SUB 0.887 0.870 0.850 0.877 0.861 522898 BEARD-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.834 0.797 522903 ELMWOOD 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.768 0.718 522910 ADAMS 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.843 0.808 522911 BALKO 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.775 0.725 522916 ELMWOOD-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.768 0.718 522917 ADAMS-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.846 0.811 522918 COLE 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.792 0.746 522923 TURPIN 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.805 0.762 522927 JEFFERSON 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.877 0.847 522934 TURPIN-T 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.806 0.764 522943 BEARD 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.832 0.794 522946 HARDESTY 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.783 0.735 522947 HASKELL 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.770 0.720 522953 PONDEROSA 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.803 0.759 523018 TC-HOOKER 2 69 P1.3-115/69-COLE-XFMR-50MVA 0.877 0.847 522908 PIRATE 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.929 0.918 0.927 522915 CLARK-T 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.930 0.919 0.928 522919 COUGAR 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.919 0.908 0.945 0.917 522920 ELMS_TAP 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.918 0.908 0.945 0.917 522932 MARTINEZ 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.940 0.929 0.938 522937 BLADE 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.929 0.918 0.927 522940 WILDCAT 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.919 0.908 0.945 0.917 522949 ELMS 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.918 0.908 0.945 0.916 523006 TC-ELKHART 2 69 P1.2-TX CO-HITCHLAND 115 kV CKT 1 0.940 0.929 0.938 522908 PIRATE 2 69 P2.2-THOMPSON-69 kV BUS 0.939 0.924 0.948 0.931 522915 CLARK-T 2 69 P2.2-THOMPSON-69 kV BUS 0.940 0.925 0.949 0.932 522937 BLADE 2 69 P2.2-THOMPSON-69 kV BUS 0.939 0.924 0.948 0.931 522898 BEARD-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.939 0.919 0.909 0.929 0.919 522900 GRIGGS-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.925 0.892 0.875 0.906 0.892 522901 TIE-NO 2 69 P2.2-TXCOUNTY-69KV BUS 0.911 0.872 0.850 0.891 0.871 522902 GRIGGS 2 69 P2.2-TXCOUNTY-69KV BUS 0.919 0.886 0.868 0.900 0.885 522904 LOBO 3 115 P2.2-TXCOUNTY-69KV BUS 0.928 0.903 0.889 0.915 0.902 522905 STURGIS 2 69 P2.2-TXCOUNTY-69KV BUS 0.929 0.898 0.882 0.911 0.897 522907 BOAR 2 69 P2.2-TXCOUNTY-69KV BUS 0.902 0.871 0.856 0.886 0.870 522908 PIRATE 2 69 P2.2-TXCOUNTY-69KV BUS 0.893 0.851 0.828 0.870 0.850 522909 FELT 2 69 P2.2-TXCOUNTY-69KV BUS 0.884 0.859 0.818 0.860 0.840 522910 ADAMS 2 69 P2.2-TXCOUNTY-69KV BUS 0.914 0.910 0.899 0.921 0.910 522912 Y ROAD 3 115 P2.2-TXCOUNTY-69KV BUS 0.942 0.930 0.941 522915 CLARK-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.894 0.852 0.829 0.871 0.851 522917 ADAMS-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.933 0.913 0.901 0.923 0.912 522919 COUGAR 2 69 P2.2-TXCOUNTY-69KV BUS 0.889 0.847 0.825 0.866 0.847 522920 ELMS_TAP 2 69 P2.2-TXCOUNTY-69KV BUS 0.888 0.846 0.823 0.864 0.845 522921 THRASH 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.907 0.892 0.920 0.907 522922 EVA-W 2 69 P2.2-TXCOUNTY-69KV BUS 0.917 0.879 0.857 0.898 0.878 522925 DOOLIN 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.907 0.892 0.920 0.907 522927 JEFFERSON 2 69 P2.2-TXCOUNTY-69KV BUS 0.923 0.898 0.886 0.910 0.898 522928 OPTIMA 2 69 P2.2-TXCOUNTY-69KV BUS 0.911 0.880 0.865 0.895 0.880 522929 POWELL CNR 2 69 P2.2-TXCOUNTY-69KV BUS 0.942 0.912 0.898 0.924 0.911 522930 RED DEVIL 3 115 P2.2-TXCOUNTY-69KV BUS 0.940 0.927 0.950 0.939 522932 MARTINEZ 2 69 P2.2-TXCOUNTY-69KV BUS 0.896 0.854 0.830 0.874 0.853 522935 GOODWELL 3 115 P2.2-TXCOUNTY-69KV BUS 0.941 0.928 0.940 522937 BLADE 2 69 P2.2-TXCOUNTY-69KV BUS 0.893 0.851 0.828 0.870 0.850 522940 WILDCAT 2 69 P2.2-TXCOUNTY-69KV BUS 0.889 0.847 0.825 0.866 0.847 522941 LOBO-T 3 115 P2.2-TXCOUNTY-69KV BUS 0.928 0.903 0.889 0.915 0.902 522943 BEARD 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.917 0.907 0.927 0.917 Table A2: Oklahoma Panhandle- Summer High Load Voltage Violations (cont.)

April 1, 2019

Summer High Load-Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522944 STURGIS-T 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.907 0.891 0.919 0.906 522948 PANHANDLE 2 69 P2.2-TXCOUNTY-69KV BUS 0.937 0.908 0.892 0.920 0.907 522949 ELMS 2 69 P2.2-TXCOUNTY-69KV BUS 0.888 0.846 0.823 0.864 0.845 522950 THRALL 2 69 P2.2-TXCOUNTY-69KV BUS 0.934 0.902 0.887 0.914 0.901 522954 HOVEY 3 115 P2.2-TXCOUNTY-69KV BUS 0.927 0.900 0.886 0.912 0.899 522957 POWELL CNR 3 115 P2.2-TXCOUNTY-69KV BUS 0.937 0.912 0.898 0.924 0.912 522960 PANHANDLE 3 115 P2.2-TXCOUNTY-69KV BUS 0.936 0.909 0.894 0.921 0.908 523001 TC-HOVEY 2 69 P2.2-TXCOUNTY-69KV BUS 0.915 0.884 0.870 0.899 0.884 523006 TC-ELKHART 2 69 P2.2-TXCOUNTY-69KV BUS 0.896 0.854 0.830 0.874 0.853 523018 TC-HOOKER 2 69 P2.2-TXCOUNTY-69KV BUS 0.923 0.898 0.886 0.910 0.898 523044 TC-ELKHRT_T2 69 P2.2-TXCOUNTY-69KV BUS 0.915 0.877 0.855 0.896 0.877 523065 TC-THOMPSON2 69 P2.2-TXCOUNTY-69KV BUS 0.904 0.873 0.857 0.888 0.872 523066 TUCKER 2 69 P2.2-TXCOUNTY-69KV BUS 0.904 0.873 0.857 0.888 0.872 523072 TC-SEABOARD2 69 P2.2-TXCOUNTY-69KV BUS 0.902 0.871 0.856 0.886 0.870 523099 TC-DRYTRLS 3 115 P2.2-TXCOUNTY-69KV BUS 0.923 0.898 0.884 0.910 0.897 522898 BEARD-T 2 69 P7-HITCHLAND-115KV-SUB 0.767 0.746 0.696 0.785 0.734 522899 ANTHONY 3 115 P7-HITCHLAND-115KV-SUB 0.867 0.849 0.818 0.876 0.840 522900 GRIGGS-T 2 69 P7-HITCHLAND-115KV-SUB 0.690 0.642 0.574 0.711 0.627 522901 TIE-NO 2 69 P7-HITCHLAND-115KV-SUB 0.664 0.609 0.533 0.692 0.594 522902 GRIGGS 2 69 P7-HITCHLAND-115KV-SUB 0.681 0.633 0.563 0.703 0.617 522903 ELMWOOD 2 69 P7-HITCHLAND-115KV-SUB 0.824 0.822 0.786 0.836 0.812 522904 LOBO 3 115 P7-HITCHLAND-115KV-SUB 0.708 0.665 0.601 0.728 0.650 522905 STURGIS 2 69 P7-HITCHLAND-115KV-SUB 0.699 0.652 0.585 0.719 0.637 522907 BOAR 2 69 P7-HITCHLAND-115KV-SUB 0.743 0.701 0.643 0.767 0.689 522908 PIRATE 2 69 P7-HITCHLAND-115KV-SUB 0.637 0.581 0.504 0.664 0.565 522909 FELT 2 69 P7-HITCHLAND-115KV-SUB 0.623 0.568 0.492 0.650 0.552 522910 ADAMS 2 69 P7-HITCHLAND-115KV-SUB 0.756 0.732 0.681 0.775 0.720 522911 BALKO 2 69 P7-HITCHLAND-115KV-SUB 0.830 0.829 0.794 0.842 0.819 522912 Y ROAD 3 115 P7-HITCHLAND-115KV-SUB 0.738 0.699 0.637 0.756 0.684 522914 BOYD 3 115 P7-HITCHLAND-115KV-SUB 0.874 0.857 0.826 0.883 0.848 522915 CLARK-T 2 69 P7-HITCHLAND-115KV-SUB 0.638 0.582 0.506 0.665 0.566 522916 ELMWOOD-T 2 69 P7-HITCHLAND-115KV-SUB 0.824 0.822 0.786 0.836 0.812 522917 ADAMS-T 2 69 P7-HITCHLAND-115KV-SUB 0.759 0.735 0.684 0.778 0.723 522918 COLE 2 69 P7-HITCHLAND-115KV-SUB 0.848 0.848 0.814 0.860 0.838 522919 COUGAR 2 69 P7-HITCHLAND-115KV-SUB 0.632 0.577 0.502 0.658 0.561 522920 ELMS_TAP 2 69 P7-HITCHLAND-115KV-SUB 0.630 0.575 0.499 0.656 0.559 522921 THRASH 2 69 P7-HITCHLAND-115KV-SUB 0.710 0.664 0.598 0.729 0.649 522922 EVA-W 2 69 P7-HITCHLAND-115KV-SUB 0.673 0.618 0.543 0.701 0.603 522923 TURPIN 2 69 P7-HITCHLAND-115KV-SUB 0.801 0.789 0.745 0.817 0.778 522925 DOOLIN 2 69 P7-HITCHLAND-115KV-SUB 0.710 0.664 0.598 0.729 0.649 522926 BOURK 2 69 P7-HITCHLAND-115KV-SUB 0.762 0.721 0.664 0.786 0.709 522927 JEFFERSON 2 69 P7-HITCHLAND-115KV-SUB 0.743 0.713 0.659 0.763 0.701 522928 OPTIMA 2 69 P7-HITCHLAND-115KV-SUB 0.725 0.682 0.622 0.748 0.669 522929 POWELL CNR 2 69 P7-HITCHLAND-115KV-SUB 0.721 0.675 0.611 0.738 0.660 522930 RED DEVIL 3 115 P7-HITCHLAND-115KV-SUB 0.734 0.695 0.633 0.752 0.680 522931 REED 2 69 P7-HITCHLAND-115KV-SUB 0.762 0.721 0.664 0.786 0.709 522932 MARTINEZ 2 69 P7-HITCHLAND-115KV-SUB 0.640 0.583 0.505 0.670 0.567 522934 TURPIN-T 2 69 P7-HITCHLAND-115KV-SUB 0.800 0.787 0.742 0.815 0.776 522935 GOODWELL 3 115 P7-HITCHLAND-115KV-SUB 0.736 0.697 0.634 0.754 0.681 522937 BLADE 2 69 P7-HITCHLAND-115KV-SUB 0.637 0.581 0.504 0.664 0.565 522940 WILDCAT 2 69 P7-HITCHLAND-115KV-SUB 0.632 0.577 0.502 0.658 0.561 522941 LOBO-T 3 115 P7-HITCHLAND-115KV-SUB 0.708 0.666 0.601 0.728 0.650 522942 LITTAU 3 115 P7-HITCHLAND-115KV-SUB 0.873 0.856 0.825 0.882 0.846 522943 BEARD 2 69 P7-HITCHLAND-115KV-SUB 0.764 0.743 0.693 0.782 0.731 522944 STURGIS-T 2 69 P7-HITCHLAND-115KV-SUB 0.710 0.664 0.598 0.729 0.649 522946 HARDESTY 2 69 P7-HITCHLAND-115KV-SUB 0.839 0.838 0.803 0.850 0.828 522947 HASKELL 2 69 P7-HITCHLAND-115KV-SUB 0.825 0.824 0.788 0.838 0.814 522948 PANHANDLE 2 69 P7-HITCHLAND-115KV-SUB 0.710 0.664 0.598 0.729 0.649 522949 ELMS 2 69 P7-HITCHLAND-115KV-SUB 0.630 0.575 0.499 0.656 0.559 522950 THRALL 2 69 P7-HITCHLAND-115KV-SUB 0.709 0.662 0.596 0.726 0.646 522952 ROSE 3 115 P7-HITCHLAND-115KV-SUB 0.857 0.839 0.807 0.867 0.830 522953 PONDEROSA 2 69 P7-HITCHLAND-115KV-SUB 0.796 0.783 0.738 0.811 0.772 Table A2: Oklahoma Panhandle- Summer High Load Voltage Violations (cont.)

April 1, 2019

Summer High Load-Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 522954 HOVEY 3 115 P7-HITCHLAND-115KV-SUB 0.723 0.682 0.620 0.744 0.668 522957 POWELL CNR 3 115 P7-HITCHLAND-115KV-SUB 0.720 0.679 0.615 0.740 0.664 522960 PANHANDLE 3 115 P7-HITCHLAND-115KV-SUB 0.714 0.670 0.605 0.734 0.655 523001 TC-HOVEY 2 69 P7-HITCHLAND-115KV-SUB 0.730 0.687 0.628 0.753 0.675 523006 TC-ELKHART 2 69 P7-HITCHLAND-115KV-SUB 0.640 0.583 0.505 0.670 0.567 523012 TC-ANTHY_TP3 115 P7-HITCHLAND-115KV-SUB 0.867 0.849 0.818 0.876 0.840 523018 TC-HOOKER 2 69 P7-HITCHLAND-115KV-SUB 0.743 0.713 0.659 0.763 0.701 523024 TC-BEAVER 3 115 P7-HITCHLAND-115KV-SUB 0.857 0.839 0.807 0.867 0.830 523044 TC-ELKHRT_T2 69 P7-HITCHLAND-115KV-SUB 0.671 0.616 0.540 0.699 0.601 523051 TC-EVAREG 2 69 P7-HITCHLAND-115KV-SUB 0.617 0.567 0.499 0.642 0.553 523065 TC-THOMPSON2 69 P7-HITCHLAND-115KV-SUB 0.741 0.698 0.640 0.765 0.686 523066 TUCKER 2 69 P7-HITCHLAND-115KV-SUB 0.741 0.698 0.640 0.765 0.686 523072 TC-SEABOARD2 69 P7-HITCHLAND-115KV-SUB 0.743 0.701 0.643 0.767 0.689 523089 TC-TXCOUNTY2 69 P7-HITCHLAND-115KV-SUB 0.762 0.721 0.664 0.786 0.709 523099 TC-DRYTRLS 3 115 P7-HITCHLAND-115KV-SUB 0.701 0.659 0.594 0.722 0.644 523113 TC-MCMURRY 3 115 P7-HITCHLAND-115KV-SUB 0.773 0.740 0.685 0.788 0.726 523142 TC-AGGIE 3 115 P7-HITCHLAND-115KV-SUB 0.864 0.845 0.813 0.873 0.836 523090 TEXAS_CNTY 3 115 P7-HITCHLAND-115KV-SUB 0.764 0.729 0.670 0.779 0.714 523106 TXPHSF 3 115 P7-HITCHLAND-115KV-SUB 0.783 0.751 0.690 0.793 0.736 523120 COLE 3 115 P7-HITCHLAND-115KV-SUB 0.874 0.857 0.826 0.883 0.848

Table A2: Oklahoma Panhandle- Summer High Load Voltage Violations (cont.)

April 1, 2019

APPENDIX B

From Bus To Bus Base Load-Thermal Loading % Ckt ID Contingency Number Name kV Number Name kV 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505594-300895(1) 103.03 105.74 116.82 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505574-505594(1) 105.24 105.38 118.38 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505570-505588(1) 107.63 108.61 122.70 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505570-505574-505576(1) 101.40 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505552-512644-512832(1) 101.69 505460 BULL SH5 161 338813 5MIDWAY# 161 1 SINGLE 505460-338123(1) 102.41 505440 DONIPHN5 161 301201 2DONIPH 69 1 SINGLE 505440-301201(2) 111.26 116.95 124.71 110.10 113.68 505434 IDALIA 5 161 301243 2IDALIA 69 1 SINGLE 505434-301243(2) 100.70 102.78 523304 MOORE_W 3 115 523315 RB-S&S 3 115 1 SINGLE 523332-523339(1) 115.33 523304 MOORE_W 3 115 523315 RB-S&S 3 115 1 SINGLE 523339-524043(1) 120.85 523106 TXPHSF 3 115 539672 E-LIBER3 115 1 P7 HITCHLAND 115kV SUB 112.50

Table B1: External Area- Base Load- Thermal Overloads

From Bus To Bus Summer High Load-Thermal Loading % Ckt ID Contingency Number Name kV Number Name kV 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505594-300895(1) 103.34 105.85 116.92 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505574-505594(1) 105.74 105.62 118.63 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505570-505588(1) 108.43 108.98 123.09 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505570-505574-505576(1) 101.64 505588 STIGLER5 161 300877 2STIGLER 69 1 SINGLE 505552-512644-512832(1) 101.81 505460 BULL SH5 161 338813 5MIDWAY# 161 1 SINGLE 505460-338123(1) 102.40 505440 DONIPHN5 161 301201 2DONIPH 69 1 SINGLE 505440-301201(2) 111.77 117.11 124.89 110.23 113.84 505434 IDALIA 5 161 301243 2IDALIA 69 1 SINGLE 505434-301243(2) 100.72 102.81 523304 MOORE_W 3 115 523315 RB-S&S 3 115 1 SINGLE 523332-523339(1) 115.50 523304 MOORE_W 3 115 523315 RB-S&S 3 115 1 SINGLE 523339-524043(1) 121.04 523113 TC-MCMURRY 3 115 523090 TEXAS_CNTY 3 115 1 P7 HITCHLAND 115kV SUB 118.30 122.73 115.08 112.47 121.90 523142 TC-AGGIE 3 115 523120 COLE 3 115 1 P7 HITCHLAND 115kV SUB 123.70 128.49 121.83 118.37 127.95 523106 TXPHSF 3 115 539672 E-LIBER3 115 1 P7 HITCHLAND 115kV SUB 103.59 109.03 143.48 103.82 114.01

Table B2: External Area- Summer High Load- Thermal Overloads

Base Load -Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 523221 XIT_INTG 6 230 SINGLE 523221-523869(1) 0.891 0.883 0.890 523315 RB-S&S 3 115 SINGLE 523304-523315(1) 0.880 0.795 0.896 0.880 523318 DUMAS_19ST 3 115 SINGLE 523304-523315(1) 0.889 0.806 0.889 523325 EXELL 3 115 SINGLE 523304-523315(1) 0.855 523332 EXELL_TP 3 115 SINGLE 523304-523315(1) 0.857 523339 FAIN 3 115 SINGLE 523304-523315(1) 0.890 523318 DUMAS_19ST 3 115 SINGLE 523315-523318(1) 0.876 523221 XIT_INTG 6 230 SINGLE 523869-523959(1) 0.880 0.868 0.880 523869 CHAN+TASCOS6 230 SINGLE 523869-523959(1) 0.878 0.866 0.878 523227 RB-DALLAM 2 69 SINGLE 523869-523959(1) 0.898

Table B3: External Area- Base Load- Voltage Violations

April 1, 2019

Summer High Load-Voltage (p.u.) Bus Number Bus Name Bus kV Contingency 2019 S0 2022 S0 2027 S0 2019 SBR 2022 SBR 523221 XIT_INTG 6 230 SINGLE 523221-523869(1) 0.889 0.880 0.889 523315 RB-S&S 3 115 SINGLE 523304-523315(1) 0.897 0.880 0.796 0.896 0.880 523318 DUMAS_19ST 3 115 SINGLE 523304-523315(1) 0.889 0.806 0.889 523325 EXELL 3 115 SINGLE 523304-523315(1) 0.856 523332 EXELL_TP 3 115 SINGLE 523304-523315(1) 0.857 523339 FAIN 3 115 SINGLE 523304-523315(1) 0.890 523318 DUMAS_19ST 3 115 SINGLE 523315-523318(1) 0.876 523772 COBRN_CREEK3 115 SINGLE 523776-523777-523774(1) 1.089 523776 WHEELER 3 115 SINGLE 523776-523777-523774(1) 1.079 523782 MAGIC_CITY 2 69 SINGLE 523776-523777-523774(1) 1.061 523789 GB-WHEELER 2 69 SINGLE 523776-523777-523774(1) 1.066 523796 HOWARD 2 69 SINGLE 523776-523777-523774(1) 1.066 523797 HOWARD 3 115 SINGLE 523776-523777-523774(1) 1.072 523221 XIT_INTG 6 230 SINGLE 523869-523959(1) 0.878 0.865 0.879 523869 CHAN+TASCOS6 230 SINGLE 523869-523959(1) 0.876 0.863 0.877 523220 XIT_INTG 3 115 SINGLE 523869-523959(1) 0.898 523227 RB-DALLAM 2 69 SINGLE 523869-523959(1) 0.895 523228 DALLAM 3 115 SINGLE 523869-523959(1) 0.898 523237 HILMARCHZ 3 115 SINGLE 523869-523959(1) 0.900 523246 DALHART 3 115 SINGLE 523869-523959(1) 0.898

Table B4: External Area- Summer High Load- Voltage Violations

April 1, 2019

APPENDIX C

From Bus To Bus Thermal Loading % Ckt ID Contingency Number Name kV Number Name kV SHL 19S Base 22S SHL 27S 523001 TC-HOVEY 2 69 523065 TC-THOMPSON2 69 1 P1.2-Y-RD - TX CO 115 kV 106.1 100.4 114.5 523001 TC-HOVEY 2 69 523065 TC-THOMPSON2 69 2 P1.2-Y-RD - TX CO 115 kV 106.1 100.4 114.5 523001 TC-HOVEY 2 69 523065 TC-THOMPSON2 69 1 P1.2-Y-RD - POWELL CORNER 115 kV - - 101.5 523001 TC-HOVEY 2 69 523065 TC-THOMPSON2 69 2 P1.2-Y-RD - POWELL CORNER 115 kV - - 101.5 Table C1: Thermal Overloads- Y-Road Station

Y-Road Single Line Outage- Lowest Voltage (p.u.) Base Load Summer High Load Contingency Low Voltage Impact 2019 S 2022 S 2027 S 2019 S 2022 S 2027 S P1.2-Y-RD - TX CO 115 kV Western, Hovey to Cougar 0.87 0.80 0.80 0.83 0.81 0.79 P1.2-Y-RD - POWELL CORNER 115 kV Western, Hovey to Cougar 0.92 0.90 0.88 0.85 0.83 0.82 Table C2: Low Voltage- Y-Road Station