SYSTEM IMPACT RESTUDY H252W ERIS REPORT. El Paso Electric Company

Transcription

1 SYSTEM IMPACT RESTUDY H252W ERIS REPORT Prepared for: El Paso Electric Company Prepared by: Engineers, LLC 1526 Cole Boulevard Building 3, Suite 150 Lakewood, CO (303)

2 FOREWORD This report was prepared for the purpose of addressing the system impacts of the identified project of the Interconnection Customer, at the request of System Planning at El Paso Electric Company. Any correspondence concerning this document, including technical and commercial questions, should be referred to: David Tovar Manager System Planning Department El Paso Electric Company 100 North Stanton, Loc. 751 El Paso, Texas Phone: (915) Fax: (915) Or Roberto Favela Principal Engineer El Paso Electric Company 100 North Stanton, Loc. 751 El Paso, Texas Phone: (915) Fax: (915) i

3 Table of Contents EXECUTIVE SUMMARY INTRODUCTION H252W PROJECT DESCRIPTION STUDY METHODOLOGY PROCEDURE, ASSUMPTIONS & CRITERIA DEVELOPMENT AND DESCRIPTION OF POWER FLOW CASES DYNAMIC STABILITY MODELING DYNAMIC STABILITY MODELING STEADY STATE POWER FLOW ANALYSIS NORMAL OPERATING CONDITION POWER FLOW EVALUATION Pre-project P0 Outage Power Flow Evaluation Post-project P0 Outage Power Flow Evaluation EMERGENCY OPERATING CONDITION POWER FLOW EVALUATION Pre-project P1-P7 Power Flow Evaluation Post-project P1-P7 Power Flow Evaluation ERIS EVALUATION POWER FLOW ANALYSIS CONCLUSION STEADY STATE VOLTAGE ANALYSIS NORMAL OPERATING CONDITION VOLTAGE EVALUATION EMERGENCY OPERATING CONDITION VOLTAGE EVALUATION DELTA VOLTAGE EVALUATION POWER FACTOR TEST STEADY STATE VOLTAGE ANALYSIS CONCLUSIONS SHORT CIRCUIT ANALYSIS SHORT CIRCUIT ANALYSIS PROCEDURE SHORT CIRCUIT ANALYSIS MODELING SHORT CIRCUIT ANALYSIS RESULTS AND CONCLUSION STABILITY ANALYSIS STABILITY STUDY CASE DEVELOPMENT AND H252W STABILITY MODELING ERIS STABILITY ANALYSIS & RESULTS LOW VOLTAGE RIDE THROUGH TEST STABILITY ANALYSIS CONCLUSION COST ESTIMATES, COST ALLOCATION, & PROJECT SCHEDULE H252W PRELIMINARY COST ESTIMATES H252W ERIS INTERCONNECTION SCHEDULE DISCLAIMER CONCLUSIONS List of Tables TABLE 2-1: TRANSMISSION SYSTEM PERFORMANCE CRITERIA... 6 TABLE 2-2: SENIOR QUEUED PROJECTS AND ASSOCIATED NETWORK UPGRADES... 7 TABLE 2-2: CASE DISPATCH... 7 TABLE 3-1: H252W ERIS DISPATCH RESULTS... 9 TABLE 4-1: POWER FACTOR TEST RESULTS TABLE 5-1: H252W PROJECT SHORT CIRCUIT MODELING DATA TABLE 7-1: EPE INTERCONNECTION FACILITIES COSTS FOR H252W (PRIMARY POI) TABLE 7-2: SUBSTATION NETWORK INTERCONNECTION FACILITIES COSTS FOR H252W (PRIMARY POI) TABLE 7-3: EPE INTERCONNECTION FACILITIES COSTS FOR H252W (ALTERNATE POI) TABLE 7-4: SUBSTATION NETWORK INTERCONNECTION FACILITIES COSTS FOR H252W (ALTERNATE POI) ii

4 List of Figures FIGURE 1-1: EPE 2022 TRANSMISSION MAP WITH H252W POI... 4 FIGURE 7-1: H252W CONCEPTUAL ONE-LINE (PRIMARY POI) FIGURE 7-2: H252W CONCEPTUAL ONE-LINE (ALTERNATE POI) Appendices APPENDIX A APPENDIX B APPENDIX C APPENDIX D PROJECT MODELING INFORMATION CONTINGENCY LISTS STABILITY ANALYSIS RESULTS PRELIMINARY INTERCONNECTION SCHEDULE iii

5 252W ERIS System Impact Restudy Report EXECUTIVE SUMMARY The objective of this System Impact Study (SIS) was to evaluate potential impacts to the Study Area (defined as the EPE system and the PNM system in southern New Mexico) transmission system caused by the requested addition of the H252W generator interconnection project. The proposed project has requested Energy Resource Interconnection Service (ERIS 1 ). The H252W Project is comprised of up to 252 MW of wind powered generation. The H252W Point Of Interconnection (POI) is proposed at the Hidalgo 345 kv substation (Primary POI). An Alternative POI was requested to tap the Hidalgo to Luna 345 kv line approximately nine (9) miles east of the Hidalgo Substation. Given the location of the proposed interconnection on a jointly owned substation (Primary POI) or a jointly owned transmission line (Alternate POI), EPE has identified the joint owner, Public Service Company of New Mexico (PNM), as an Affected System for this SIS. For the ERIS evaluation, Short Circuit, Steady State, and Stability contingency analyses were performed using all applicable standards from EPE, PNM, the Western Electric Coordinating Council (WECC), and the North American Electric Reliability Corporation (NERC). To resolve any observed criteria violations, H252W generation was reduced until all violations were resolved. Transmission Service Disclaimer to EPE Customer Please note that this SIS Report addresses generation interconnection upgrades and requirements only. This SIS Report does not address or imply any right to receive transmission service from EPE or any other transmission provider. SIS Results Summary Steady State Results Steady State analysis was completed by applying applicable NERC Transmission Planning Performance Requirements (TPL) planning scenarios P0-P7. Results showed that no overloaded transmission facilities were present in the Study Area under P0-P7 conditions after the addition of the H252W Project. Although no thermal violations were observed, the H252W Project ERIS output may be limited by the Available Transfer Capability (ATC) on the transmission path from the Hidalgo Substation to the Luna Substation. (See Section 3.3 for details.) Voltage analysis results also showed no criteria violations under NERC TPL P0-P7 planning scenarios. Power Factor Test results showed that the H252W Project, as designed, can maintain the required leading and lagging 0.95 pu power factor. Short Circuit Results 1 Energy Resource Interconnection Service (ERIS) shall mean an Interconnection Service that allows the Interconnection Customer to connect its Generating Facility to the Transmission Provider's Transmission System to be eligible to deliver the Generating Facility's electric output using the existing firm or non-firm capacity of the Transmission Provider's Transmission System on an as available basis. Energy Resource Interconnection Service in and of itself does not convey transmission service. 1

6 A Short Circuit analysis was performed to determine if the addition of the H252W Project would cause any existing EPE transmission system circuit breakers to exceed their interrupting ratings. Results of the short circuit study showed that the addition of the H252W Project did not cause any existing EPE circuit breakers to exceed their interrupting capability. Stability Results Dynamic models for the H252W Project were added to the EPE databases. The H252W Project dynamic model consists of all WECC required sub-models and appropriate voltage and frequency parameters to comply with Low Voltage Ride Through criteria Transient system stability analysis was completed for relevant faults under both Peak and Off Peak load conditions. Low Voltage Ride Through (LVRT) test was also completed to show that the Project can withstand a 9 cycle 3-phase and a 18 cycle single-phase fault at the 345 kv high side of its Main Power Transformer (MPT). The analysis verified the H252W generator response and the EPE system response to each fault. Results show that the H252W Project and the EPE system remained stable and positively damped for all simulations tested. Cost Estimates and Schedule Good faith cost estimates are presented in Section 7.0. The general cost estimates provided in this study are in 2018 dollars with an accuracy of +/-50% (no escalation applied). To that end, all cost estimates included in this report are subject to change during the Facilities Study phase of the EPE interconnection process. The estimates are based upon typical construction costs for previously performed similar construction. These costs include estimated applicable labor and overheads associated with the engineering, design, and construction of these new interconnection facilities. These estimates did not include the Generator Interconnection Costs for any other Interconnection Customer owned equipment or associated design and engineering except for the POI facilities. Interconnection Customers are also responsible for all Generator Interconnection Costs 2 to construct facilities that meet the joint owners (EPE and PNM) design criteria. Generator Interconnection Cost estimates to construct Interconnection Customer owned facilities have not been provided in this report. For H252W interconnection at the Primary POI, the estimated total cost for the required upgrades is $3.49 Million. This breaks down to $0.77 Million for the Interconnection Costs at the POI, and $2.72 Million for the Network Upgrade (Hidalgo Substation) Costs. For H252W interconnection with at the Alternate POI, the estimated total cost for the required upgrades is $10.45 Million. This breaks down to $1.05 Million for the Interconnection Costs at the POI and $9.40 Million for the H252W POI Network (substation) Upgrade Costs. The estimated time frame for Engineering, Procurement, and Construction for interconnection at either the Primary or Alternate POI for H252W is approximately 48 months upon notice to proceed with construction from the Interconnection Customer. 2 Generator Interconnection Costs: cost of facilities paid for by Interconnection Customer and owned and operated by the Interconnection Customer from the generator facilities to the Change of Ownership Point, which is typically on the first dead-end at the Point of Interconnection substation. 2

7 Conclusions The objective of this System Impact Study SIS was to evaluate potential impacts to the Study Area transmission facilities caused by the requested addition of the H252W generator interconnection project. The proposed project has requested ERIS to interconnect 252 MW of wind turbine generation at the jointowned (EPE and PNM) Hidalgo 345 kv Substation, the requested POI. Short Circuit, Steady State, and Stability contingency analyses were performed using all applicable standards from EPE, PNM, WECC, and NERC. To resolve any observed criteria violations, H252W generation was reduced until all violations were resolved. Although no criteria violations were observed, the H252W Project ERIS output may be limited by the ATC on the transmission path from the Hidalgo Substation to the Luna Substation. (See Section 3.3 for details.) For H252W interconnection at the Primary POI, the estimated total cost for the required Interconnection Facilities is $3.49 Million. For H252W interconnection with at the Alternate POI, the estimated total cost for the required upgrades is $10.45 Million. This breaks down to $1.05 Million for the Interconnection Costs at the POI and $9.40 Million for the H252W POI Network Upgrade Costs. The estimated time frame for Engineering, Procurement, and Construction for interconnection at either the Primary or Alternate POI for H252W is approximately 48 months upon notice to proceed with construction from the Interconnection Customer. 3

8 1.0 INTRODUCTION The Federal Energy Regulatory Commission (FERC) requires that a SIS be performed for generation facilities desiring to connect to any Transmission System. Here, the Interconnection Customer seeks to interconnect to the EPE Transmission System and to have its generating facility studied for ERIS. During the ERIS analysis, H252W generation was reduced until all criteria violations were resolved. Steady State, Stability, and Short Circuit analyses were performed to determine the impact the H252W ERIS request would have on the EPE Transmission System. Steady State and Stability analyses were performed using study cases for EPE planning year 2022 with both Peak and Off Peak loads. As a joint owner in the facilities at both the Primary POI and Alternate POI, EPE has identified PNM as an Affected System for this SIS, so the Study Areas for the analyses were limited to WECC Areas 11 - EPE and 10 - PNM. The study was performed in accordance with applicable standards for WECC, NERC, PNM and EPE. The EPE local reliability standards can be found in Section 4 of EPE s FERC Form No The Steady State and Stability analyses were performed using General Electric s (GE) Power System Load Flow (PSLF) software Version 19. Short Circuit analysis was performed using a 2022 study year while utilizing Aspen Oneliner software Version H252W Project Description The H252W Project is comprised of up to 252 MW of wind powered generation. The H252W POI is proposed at the Hidalgo 345 kv substation. An Alternative POI was requested to tap the Hidalgo to Luna 345 kv line approximately nine (9) miles east of the Hidalgo Substation. Figure 1-1 shows the proposed POI for the H252W Project. A project one-line and model information are including in Appendix A. The H252W Project will consist of seventy-four (74) wind turbine generators rated at 3.4 MW each. The proposed inverters are manufactured by Senvion. The turbines are to be installed at a terminal voltage of kv. This initial voltage would be immediately stepped up to the 34.5 kv collector voltage that is planned for the PV installation. A pair of 345/34.5 kv main transformers will then step up the collector voltage to the 345 kv Transmission System voltage, then an overhead transmission line will connect the H252W Project to an existing open breaker bay at the Hidalgo 345 kv Substation. Figure 1-1: EPE 345 kv Transmission System with H252W Primary POI 4

9 2.0 STUDY METHODOLOGY 2.1 Procedure, Assumptions & Criteria To test the H252W Project for ERIS, Steady State and Stability analyses were completed. A Short Circuit Duty Analysis and Steady State Power Factor Test were also completed to determine the H252W impacts to the system. The following assumptions are consistent for all study scenarios unless otherwise noted. The Study Areas for the ERIS analysis were limited to Western Electric Coordinating Council (WECC) Areas 11 - EPE and 10 PNM. This study assumed that all system expansion projects as planned by area utilities by the year under analysis are completed, and that any system improvements already identified as required by the interconnections senior to H252W are implemented. For projects senior to the H252W Project, this study did not analyze any transmission service from the senior-queued interconnection points to any specific point(s) of delivery on the EPE transmission system. For running the various studies, EPE assumed that H252W Project generation was dispatched and delivered to the EPE native load. This does not mean that the H252W Project was studied for NRIS service. Similarly, this does not mean that the study evaluates the availability of transmission capability on the EPE transmission system to delivery H252W generation. To the extent the Interconnection Customer were to seek to transmit the Project generation to a particular delivery point on the EPE Transmission System, additional studies would have to be conducted as part of a point-to-point transmission service request. Transformer tap and phase-shifting transformer angle movement, as well as static var device switching, were allowed for the steady state pre-contingency analysis. All regulating equipment such as transformer controls and switched shunts were fixed at pre-contingency positions when the contingency analysis was performed. For post-contingency analysis Static var device switching was allowed, but all other regulation equipment was locked. All facility loadings at voltages 69 kv and greater were monitored within the Study Area Precontingency and Post-contingency flows on lines and transformers were required to remain at or below the normal rating, while post-contingency flows on lines and transformers were required to remain at or below the emergency rating. Flows above 100% of an element s pre-project or postcontingency rating were considered violations. All post-project voltage criteria violations that improve an existing pre-project violation were not considered an adverse impact to the system. The transmission performance criteria utilized for qualifying violations in the study area are shown in Table

10 Table 2-1: Transmission System Performance Criteria VOLTAGE UTILITY ALIS (pu) - P0 N-1 (pu) - P1 ΔV (%) - P1 N-2 (pu) - P2-P7 ALIS (Normal) LINE LOADING (% Rating) N-1 - P1 (Emergency) N-2 - P2-P7 (Emergency) TEP 138 kv TEP 345 kv TEP 500 kv TSGT (Subject to TSGT Comments) PNM (Subject to PNM Comments) EPE At Transmission Buses BES Buses (Assumed 100 kv and Above) Taiban Mesa, Jicarilla, and Clines kv buses At Transmission Buses BES Buses (Assumed 100 kv and Above) Taiban Mesa, Jicarilla, and Clines kv buses 8 At Transmission Buses 8 BES Buses (Assumed 100 kv and Above) 8 Taiban Mesa and Guadalupe 345 kv buses At Transmission Buses BES Buses (Assumed 100 kv and Above) Taiban Mesa, Jicarilla, and Clines kv buses 80/ (115 kv) (115 kv) (345 kv buses) (Greenlee 345 kv is 8%) Note: Only buses 100 kv or above shall be examined when applying TPL Powerflow Criteria 1 For extreme event, per TPL-001-4, for the steady state and Stability Portion of the Planning Assessment, EPE will follow the requirements of Sections 3.5 and 4.5, respectively: if the analysis concludes there is Cascading caused by the occurrence of extreme event, an evaluation of possible actions designed to reduce the likelihood or mitigate the consequences and adverse impacts of the event(s) shall be conducted as the criteria or guidance for extreme events in Table 1 for extreme events of TPL P0 through P7 refers to the categories of contingencies identified in Table 1 of NERC Standard TPL-001-4, Transmission System Planning Performance Requirements. 3 Default criteria assumed following TPL-001-WECC-CRT3 in lieu of communicated criteria. 4 Exceptions may be granted for high side buses of Load-Tap-Changing (LTC) transformers that violate this criterion, if the corresponding low side busses are well within the criterion. 5 Planned station 6 69 KV voltage criteria as per EPE's latest FERC Form 715 filing. 6

11 2.2 Development and Description of Power Flow Cases Two benchmark study cases, a 2022 Heavy Summer (Peak) and 2021/2022 Light Winter (Off Peak), were provided by EPE to develop the ERIS study cases. The Eddy County HVDC is on-line in the Peak case scenarios and off-line in the Off Peak cases. Afton Generation was modeled in service for Peak cases and out of service for Off Peak cases. The Arroyo Phase Shifter was modeled to provide MW N-S flow under Peak cases and MW N-S flow during the Off Peak cases. Table 2-2: Senior Queued Projects and Associated Network Upgrades Cluster Window Project Name Associated Network Upgrades Fall 2014 DS90S None Spring 2016 CA200S Add Corona 345 kv Substation Spring 2017 N200S None Table 2-2 lists the senior queued projects and associated network upgrades that were included in the SIS base cases. The pre-project base cases were developed by dispatching all senior queued generation to serve and offset EPE native load. The DS90S Project is planned as a 90 MW installation that plans to interconnect at a to-be-constructed substation that will tap the existing Diablo-to-Santa Teresa 115 kv transmission line. The CA200S is a planned 200 MW solar installation with a POI at the (planned) Corona 345 kv Substation. The N200S Project is a 170 MW solar installation planned to interconnect at the Newman 115 kv Substation. Post-project power flow base cases were then developed by dispatching the H252W generation to serve and offset EPE native load. Automated change files to include the H252W Project into a PSLF power flow model are provided in Appendix B. Table 2-3 shows the power flow generation dispatch in the base cases that were developed and tested during the. 2.3 Dynamic Stability Modeling Table 2-3: Case Dispatch HEAVY SUMMER CASES (MW) Study Case Scenarios EPE LOCAL IMPORT H252W 2022HS_Pre (RIOGD_G8) HS_Post (MPS) LIGHT WINTER CASES (MW) Study Case Scenarios EPE LOCAL IMPORT H252W 2022LW_Pre (RIOGD_G8) LW_Post (RIOGD_G8) Appendix A includes dynamic modeling data for the H252W Project. The dynamic model consists of the WECC required sub-models: regc_a, reec_a, wtgq_a, wtgt_a, wtga_a, wtgp_a. The dynamic models include appropriate voltage and frequency parameters to comply with Low Voltage Ride Through criteria. 2.4 Dynamic Stability Modeling The steady state and stability contingency lists used for the H252W SIS can be found in Appendix B. All contingencies were selected in accordance with NERC TPL criteria, and based on engineering judgment to represent a cross section of contingencies that would stress the Study Area system. 7

12 3.0 STEADY STATE POWER FLOW ANALYSIS This section provides a high-level understanding of the impact H252W would have on the loading of transmission lines and transformers in the Study Area. During the SIS Peak and Off Peak base cases were evaluated for thermally overloaded facilities under all applicable P0-P7 planning outages, as described in NERC TPL To determine Project impacts, the analysis was completed using the cases described in Table Normal Operating Condition Power Flow Evaluation Pre-project P0 Outage Power Flow Evaluation Power flow analysis was completed under system Normal (P0) conditions before the addition of the H252W Project using both the Peak and Off Peak cases. Power flow analysis results showed no overloaded transmission facilities were present in the Study Area under Normal (P0) system conditions prior to the addition of the H252W Project Post-project P0 Outage Power Flow Evaluation Power flow analysis under system Normal conditions was also completed after the addition of the H252W Project using both the Peak and Off Peak cases. Power flow analysis results continued to show no overloaded transmission facilities were present in the Study Area under Normal (P0) system conditions after the addition of the H252W Project. 3.2 Emergency Operating Condition Power Flow Evaluation Pre-project P1-P7 Power Flow Evaluation Contingency power flow analysis was completed by testing the P1-P7 contingencies listed in Appendix B. Both the Peak and Off Peak cases were tested before the addition of the H252W Project. Power flow analysis results showed no overloaded transmission facilities were present in the EPE area under P1-P7 conditions prior to the addition of the H252W Project Post-project P1-P7 Power Flow Evaluation Contingency power flow analysis was completed on the Peak and Off Peak cases after the addition of the H252W Project. Power flow analysis results continued to show no overloaded transmission facilities were present in the EPE area under P1-P7 conditions after the addition of the H252W Project. 3.3 ERIS Evaluation Although no thermal violations were observed during the SIS Steady State evaluation, the H252W Project output may be limited by the Available Transfer Capability (ATC) on the transmission path from the Hidalgo Substation to the Luna Substation. EPE is not the sole owner of the Hidalgo to Luna 345 kv line. Of EPE s share of the line s capacity, currently the maximum Available Transmission Capacity (at the time of the preparation of this study) is 104 MW. This is the maximum portion of ATC that may be offered by EPE on as available basis under current facts and circumstances. Of course, the amount of ATC available for use by a transmission customer seeking to transmit H252W generation may change, over time, and would be assessed at the time of a transmission service request. 8

13 Table 3-1: H252W ERIS Dispatch Results H252W Dispatch Maximum Potential ERIS Dispatch assuming availability at the time desired H252W ERIS Generation (MW) Power Flow Analysis Conclusion NERC TPL planning event conditions P0-P7 were tested to evaluate the impacts of adding the H252W Project to the EPE Study Area transmission system. Table 3-1 shows the maximum potential ERIS dispatch, assuming availability. Actual availability may differ. ERIS allows the Interconnection Customer to connect its Generating Facility to the Transmission Provider's Transmission System to be eligible to deliver the Generating Facility's electric output using the existing firm or non-firm capacity of the Transmission Provider's Transmission System on an as available basis. It does not convey transmission service. 9

14 4.0 STEADY STATE VOLTAGE ANALYSIS Bus voltages within the Study Area were evaluated under P0-P7 outage conditions with and without the H252W Project generation in-service. The Performance Criteria shown in Table 2-1 were considered when analyzing bus voltages for violations. 4.1 Normal Operating Condition Voltage Evaluation Steady State Voltage Analysis was completed by verifying bus voltages under system Normal (P0) operating conditions in Peak and Off Peak SIS cases. Results showed no voltage violations in the Study Area under P0 system conditions before or after the addition of the H252W Project. 4.2 Emergency Operating Condition Voltage Evaluation Contingency Voltage analysis was completed by testing the P1-P7 outages listed in Appendix B. The outages were tested on the Peak and Off Peak cases before and after the addition of the H252W Project. The contingency voltage analysis showed no voltage violations in the Study Area under P1-P7 conditions before or after the addition of H252W Project. 4.3 Delta Voltage Evaluation Bus voltages within the Study Area were evaluated under P1-P7 outage conditions to determine the change in voltage due to applicable design contingencies both with and without the H252W Project generation inservice. The Performance Criteria shown in Table 2-1 were considered when analyzing bus voltages for violations. After testing all contingencies listed in Appendix B, results showed no bus voltages exceed the Delta Voltage threshold allowed by EPE Performance Criteria, 7% for 345 kv buses or 8% for the 115 kv buses. 4.4 Power Factor Test A power factor test was conducted on the H252W Project to ensure it can maintain a 0.95 pu leading and lagging power factor at each respective POI. Results in Table 4-1 show that the H252W Project is designed with the capability to absorb and provided vars past a 0.95 pu leading power factor under all tested scenarios. PF Test Location Table 4-1: Power Factor Test Results Power Factor Test Results H252W Power Factor (pu) H252W MW H252W Mvar Additional POI Reactive (Mvar) H252W MPT 345 kv Bus Leading N/A H252W MPT 345 kv Bus Lagging N/A 4.5 Steady State Voltage Analysis Conclusions NERC TPL planning event conditions P0-P7 were tested to evaluate the impacts of adding the H252W Project. Results showed that there were no voltage violations caused or worsened by the H252W Projects. Power Factor Test showed that the H252W Project, as designed, can maintain the required leading and lagging 0.95 pu power factor. 10

15 5.0 SHORT CIRCUIT ANALYSIS A short circuit analysis was performed to determine if adding of the H252W Project to the transmission system would cause any existing transmission circuit breakers to exceed their interrupting capability ratings. 5.1 Short Circuit Analysis Procedure Three phase, two phase, and single-phase-to-ground faults were simulated at all buses in the EPE and PNM systems. The ASPEN One Liner and Batch Short Circuit Module were used to perform the short circuit analyses. The short circuit fault analyses were performed with the following settings: Transmission line G+jB ignored. Shunts with positive sequence impedance ignored. Transformer line shunts ignored The pre-fault voltage was calculated using a Flat bus voltage of 1.05 per unit. Fault currents within the Study Area were analyzed before and after the addition of the H252W Project. Buses that showed an increase of 100 amps or more were reported. These scenarios were then compared against the smallest breaker interruption ratings at each substation to determine whether any breaker was over dutied under pre-project or post-project conditions. Project 5.2 Short Circuit Analysis Modeling The Short Circuit modeling data was provided by the Interconnection Customer. The generator and collector system impedance data used to model the H252W Project is listed below in Table 5-1. To determine project impacts the analysis was performed both with and without the H252W Project in service. Unit ID Pmax MW Pmin MW Table 5-1: H252W Project Short Circuit Modeling Data Generation Unit Generation Step-Up Transformer Main Transformer Qmax Mvar Qmin Mvar Z Sub-Tran Rating MVA Voltage kv Z Pos Seq Rating MVA Voltage (kv) Z Pos Seq H252W j / j /34.5/ j0.099 H252W j / j /34.5/ j Short Circuit Analysis Results and Conclusion Results of the short circuit study showed that the addition of the H252W Project did not cause any existing EPE circuit breakers to exceed their interrupting capability. 11

16 6.0 STABILITY ANALYSIS A Transient Stability analysis was performed under Peak and Off Peak load conditions to determine what impact the H252W Project will have on the transmission system stability. This analysis evaluated the performance of the system for selected faults. The purpose of this analysis is to ensure the system has adequate damping after a fault/trip event. Simulations were conducted using the PSLF power flow and dynamic simulation software, General Electric, Inc. PSLF load flow software package, Version 19 and the associated DYTools module. Dynamic stability simulations were conducted for Peak and Off Peak load conditions on the Post-project study cases discussed in Section Stability Study Case Development and H252W Stability Modeling Dynamic stability simulations were conducted for Peak and Off Peak load conditions on the Post-project study cases discussed in Section 2.2. The H252W stability control model provided was added to the EPE provided dynamic database for this part of the study. The H252W dynamic model consists of the WECC required sub-models: regc_a, reec_a, wtgq_a, wtgt_a, wtga_a, wtgp_a. 6.2 ERIS Stability Analysis & Results The Stability Contingencies List tested during this analysis is included in Appendix B. Output plots showing simulation results are provided in Appendix C for the Peak and Off Peak study cases. Results show that both the H252W Project generator and the Study Area transmission system remained stable and positively damped for all simulations tested. Stability Run Summary Results for all tested simulations are also provided in Appendix C. 6.3 Low Voltage Ride Through Test Low Voltage Ride Through (LVRT) faults were completed by testing H252W generator response to a 9 cycle 3-phase and a 18 cycle single-phase fault at the high side (or 345 kv bus) of the Project s MPT. Results show the Project remains online and stable during each of the LVRT fault simulations. 6.4 Stability Analysis Conclusion Results show that the H252W Project and the Study Area system remained stable and positively damped for all simulations tested. 12

17 7.0 COST ESTIMATES, COST ALLOCATION, & PROJECT SCHEDULE Good faith cost estimates for interconnection of the H252W Project is presented below in 2018 dollars with an accuracy of +/-50% (no escalation applied). The cost estimates are based upon costs for previously performed similar construction. These costs include estimated applicable labor and overheads associated with the engineering, design, and construction of the new facilities identified in the report. The estimates below did not include the Generator Interconnection Costs 3 or any other Interconnection Customer owned equipment or associated design and engineering except for the POI. Per EPE requirements, a Phase Measurement Unit (PMU) is included at the POI. 7.1 H252W Preliminary Cost Estimates Figure 7-1 is the conceptual one-line that was used to develop the cost estimates for H252W interconnection at the requested Primary POI. A breakdown of major cost items that are required for H252W Primary POI interconnection is shown in Table 7-1 and Figure 7-2. The conceptual one-line and cost estimate breakdowns for the H252W Alternate POI is also include in Figure 7-2, Table 7-3 and Table 7-4. As discussed in Section 1.1, the Alternate POI for H252W is the creation of a tap substation on the Hidalgo to Luna 345 kv line, approximately nine (9) miles east of the Hidalgo Substation. Figure 7-1: H252W Conceptual One-line (Primary POI) 3 Generator Interconnection Costs: cost of facilities paid for by Interconnection Customer and owned and operated by the Interconnection Customer from the generator facilities to the Change of Ownership Point, which is typically on the first dead-end at the Point of Interconnection substation. 13

18 H252W Primary POI Estimate Notes and Assumptions: 1) Substation yard is existing. Considered size for the 345kV is 400 x 400 Approx. 2) Substation Ground Grid is existing; additions will be required. 3) Fence is existing, no new fence is required. 4) Assume the existing control house is large enough for the additional relay panel and metering. 5) Lightning protection for the addition will be required. 6) Additional gravel, and leveling will be required for the addition Element Hidalgo 345 kv Substation Table 7-1: Interconnection Facilities Costs for H252W (Primary POI) Description Interconnection Facilities located at Hidalgo 345 kv Substation One 345 kv 3000 A disconnect switch w/ grounding One 345 kv Dead-end Structure One set of three (3) CVT s and Structures One (1) 345kV Gas Circuit Breaker 3000A. Three Lightning arresters and Structures One Set of 345 kv 3-Phase Metering Units and structures Relaying, communication, and testing Estimated Time Frame for Engineering, Procurement, Construction, and Commissioning Cost Est. Millions $ Months Element Hidalgo 345kV Substation Table 7-2: Network Interconnection Facilities Costs for H252W (Primary POI) Description Interconnection Facilities located at Hidalgo 345 kv Substation will comprise the following equipment and material: One (1) 345kV Switches, GOAB, Vertical Break, 3000A. One (1) 345kV Switch, GOAB, Vertical Break, 3000A, Motor operated. (1-lot) 345 kv Metering unit and accessories; including PTs, CTs, Revenue meter, Interface cabinet. Three (3) CVTs for Line Protection. (18) 345kV Bus support insulators. (1-lot) Aluminum pipe for Bus Bar work. (1- lot) Foundations for Circuit Breaker, Switches, Bus Supports. (1- lot) Grounding conductors, rods, and connectors. Two (2) Relay panels with relays, and wiring. Transmission line relaying, SCADA, communication. (1-lot) Control and other cables. (1- lot) Cable trench, and Conduits. (1) Lightning Mast, and static wire, for the addition. Estimated Time Frame for Engineering, Procurement, Construction, and Commissioning Cost Est. Millions $ Months 14

19 Figure 7-2: H252W Conceptual One-line (Alternate POI) H252W Alternate POI Estimate Notes and Assumptions: 4 1) Relay upgrades or settings at adjacent substations are not included in the estimates. 2) Prefer (4) sets of BCTs, with relay class C800 and 0.3% metering accuracy for each circuit breaker. 3) Substation yard size considered for 400 x ) Ground Grid will be required for the new substation 5) Includes fencing and gates 6) New Control House 4 The costs shown in this report are estimated costs only. The Facilities Study will provide additional details regarding costs. 15

20 7) Four Lightning masts, for lightning protection will be required. 8) Site grading and ground preparation will be required. 9) Yard lighting fixtures will be required. 10) Cable trenches and conduit system included. 11) Land cost is not included in the estimate. 12) Access road provision is not included. 13) Permitting activities are not included. Element H252W 345 kv Substation Table 7-3: Interconnection Facilities Costs for H252W (Alternate POI) Description Interconnection Facilities located at H252W POI Substation One 345 kv 3000 A disconnect switch w/ grounding One 345 kv Dead-end Structure One set of three (3) CVT s and Structures Two (2) 345kV 3000A, Gas Circuit Breakers. Three Lightning arresters and Structures One Set of 345 kv 3-Phase Metering Units and structures Relaying, communication, and testing Estimated Time Frame for Engineering, Procurement, Construction, and Commissioning Cost Est. Millions $ Months Element H252W 345 kv Substation Table 7-4: Network Facilities Costs for H252W (Alternate POI) Description The new H252W substation (345 kv) and Interconnection will require new equipment as listed below. One (1) 345kV 3000A, Gas Circuit Breakers. Two (2) 345kV Dead-end structures. (1-lot) Steel structures for; 345kV Bus Support, Surge Arresters, 345kV Switches, ad PT s. Two (2) 345kV 3000A, GOAB, disconnect switches. Six (6) CVTs, (2-sets), and structures. Six (6) Lightning Arresters (2-sets). Four (4) Shielding poles and foundations. Ninety (90) 345kV insulators for bus works. (1- lot) Transmission line relaying, SCADA, communication. (1- lot) Ground Grid system, including ground rods and Grounding conductors. Five (5) panels with relays, control modules and wiring. Transmission line relaying, SCADA, communication. (1-lot) Control cables and other cables. (1- lot) Foundations for 345 kv GCB, Switches, CVT s, Surge Arresters, and Metering Unit Dead-end structure, and lightning masts. (1- lot) Cable trench, Raceways, and Conduits (1- lot) Site prep, grading and roadways Estimated Time Frame for Engineering, Procurement, Construction, and Commissioning Cost Est. Millions $ Months 16

21 7.2 H252W ERIS Interconnection Schedule A preliminary Project Schedule for the H252W Project is provided as Appendix F. The Project Schedule includes a breakdown of the estimated time for Engineering, Procurement, Construction and Commissioning. The estimated time frame for Engineering, through Commissioning, for both Primary and Alternate POI is approximately 48 months. The time frames shown in this report are estimates, based on general industry practices. Delays may be encountered for a variety of reasons, including, but not limited to right of way acquisition, permitting, inclement weather that impedes construction, the inability to take line outages due to reliability or other reasons, delays in the posting of financial security, whether work is suspended by the Interconnection Customer, etc. 17

22 8.0 DISCLAIMER If any of the project data used in this study varies significantly from the actual data of the installed generation equipment, the results of this study may change. Any such changes may require a new Interconnection Request and/or a re-study. Additionally, any change in senior-queued projects, including senior projects that are currently in suspension, may require a re-study of the H252W Project. Facility upgrades may be associated with a request for transmission service from the Interconnection Customer s point of interconnection on the EPE system to a particular point of delivery on the EPE system, and would require separate studies based upon the specific quality of transmission service desired and the points of service identified at the time of any such transmission service requests. 18

23 9.0 CONCLUSIONS The objective of this System Impact Study SIS was to evaluate potential impacts to the Study Area transmission system caused by the requested addition of the H252W generator interconnection project. The H252W Project has requested ERIS. The H252W Project is comprised of up to 252 MW of wind powered generation. The H252W POI is proposed at the Hidalgo 345 kv substation. The interconnection customer has also requested the study of an Alternative POI that would tap the Hidalgo to Luna 345 kv line approximately nine (9) miles east of the Hidalgo Substation. Short Circuit, Steady State, and Stability contingency analyses were performed using all applicable standards from EPE, PNM, WECC, and NERC. To resolve any observed criteria violations, H252W generation was reduced until all violations were resolved. Although no criteria violations were observed, the H252W Project ERIS output may be limited by the Transmission Provider s ATC on the transmission path from the Hidalgo Substation to the Luna Substation. (See Section 3.3 for details.) For H252W interconnection at the Primary POI, the estimated total cost for the required Interconnection Facilities is $3.49 Million. For H252W interconnection with at the Alternate POI, the estimated total cost for the required facilities is $10.45 Million. This breaks down to $1.05 Million for the Interconnection Costs at the POI and $9.40 Million for the H252W POI Network Upgrade Costs. The estimated time frame for Engineering, Procurement, and Construction for interconnection at either the Primary or Alternate POI for H252W is approximately 48 months upon notice to proceed with construction from the Interconnection Customer. 19

24 Appendix A Project Modeling Information 20

25 Appendix B Contingency Lists 21

26 Appendix C Stability Analysis Results 22

27 Appendix D Preliminary Interconnection Schedule 23