ENERGY RESOURCE INTERCONNECTION SERVICE STUDY DRAFT REPORT

Transcription

1 ENERGY RESOURCE INTERCONNECTION SERVICE STUDY DRAFT REPORT ART320W 320 MW Wind Powered Project Prepared for: El Paso Electric Company Prepared by: TRC Engineers, LLC 249 Western Avenue Augusta, ME (207) February 2012

2 FOREWORD This report was prepared for the project Interconnection Customer, by System Planning at El Paso Electric Company. Any correspondence concerning this document, including technical and commercial questions should be referred to: Dennis Malone Director System Planning Department El Paso Electric Company 100 North Stanton El Paso, Texas Phone: (915) Fax: (915) Or David Gutierrez Principal Engineer El Paso Electric Company 100 North Stanton El Paso, Texas Phone: (915) Fax: (915) February 22, 2012 TRC

3 Table of Contents EXECUTIVE SUMMARY INTRODUCTION PERFORMANCE CRITERIA STUDY METHODOLOGY ASSUMPTIONS PROCEDURE Development and Description of Cases Contingency List STEADY STATE POWER FLOW ANALYSIS PRE-PROJECT POWER FLOW EVALUATION Pre-Project N-0 Flow Violations Pre-Project N-1 Flow Violations POST-PROJECT POWER FLOW EVALUATION Post-Project N-0 Power Flow Analysis Post-Project N-1 Power Flow Analysis POWER FLOW ANALYSIS CONCLUSION STEADY STATE VOLTAGE ANALYSIS COST ESTIMATES STABILITY ANALYSIS DYNAMIC MODELING STABILITY STUDY CASE DEVELOPMENT STABILITY ANALYSIS RESULTS STABILITY ANALYSIS CONCLUSION CONCLUSIONS February 22, 2012 TRC

4 List of Figures Figure 3-1: 2016 peak N-1 system condition when 231 MW generated at ART320W Figure 5-1: Artesia/Eddy County 345 kv Substation and ART320W POI Configuration List of Tables Table 1-1: EPE and New Mexico Performance Criteria... 4 Table 3-1: 2016 peak N-1 power flow analysis results Scenario Table 3-2: 2016 off peak N-1 power flow analysis results Scenario Table 3-3: 2016 peak N-1 power flow analysis results Scenario Table 3-4: 2016 off peak N-1 power flow analysis results Scenario Table 4-1: System VAR reinforcements Table 5-1: Transmission Provider Interconnection Facilities Cost Estimate Table 5-2: Artesia/Eddy County 345 kv Network Upgrade Cost Estimate Table 5-3: Artesia/Eddy County 345 kv Substation Schedule Table 6-1: Generator Models Used for Studies Appendices Appendix A Energy Resource Interconnection Study Statement of Work Appendix B Stability Plots Appendix C Dynamic Modeling Data February 22, 2012 TRC

5 Executive Summary The Energy Resource Interconnection Service (ERIS) study objective was to determine the generation level that would be allowed for the ART320W project to interconnect to the El Paso Electric (EPE) company system without requiring any Network Upgrades (except for upgrades required for interconnection of the project) on the EPE and Southern New Mexico transmission systems. A total of 320 MW of ART320W wind generation was proposed for interconnection on the Artesia/Eddy County 345 kv Substation via a 70-mile 345 kv radial line. Two senior interconnection projects in the EPE study queue that are ahead of the ART320W project were included in this Study. These two senior projects are: 1. MS99W: 50.4 MW wind powered project interconnected on the Springerville Luna 345 kv line 30 miles from Luna 345 kv station (IA with EPE). 2. DS92S: 92 MW solar powered project interconnected on the Diablo-Santa Teresa 115 kv line 5.7 miles from Diablo 115 kv station (IA with EPE). The generation from these senior projects was modeled as delivered to all entities in the Western Electricity Coordinating Council (WECC), while the ART320W generation was modeled as delivered to all WECC entities except EPE and New Mexico. Therefore, no specific transmission path for energy sales has been defined, nor does this study guarantee that a transmission path will be available when the Interconnection Customer s generation project is placed in service. El Paso operational issues, practices and standards were considered during the study process. This Study Area was limited to the WECC Area 11 - EPE (TX) and Area 10 - PNM (NM). Steady State Results The power flow analysis was conducted for peak and off peak 2016 cases, with and without the Arroyo Phase Shifter in service. The contingency analysis consisted of only one contingency - loss of Amrad-Caliente 345 kv line that caused the Amrad 345/115 kv autotransformer to overload to 130% of its 230 MVA emergency rating. The power flow results showed that the addition of the 320 MW of generation from the ART320W project to the existing system would cause power flow violations in the EPE control area for the loss of Amrad-Caliente 345 kv line, with or without the Arroyo Phase Shifter in service. The power flow analysis showed that up to 231 MW, generated by the ART320W project, could be added to the existing system without any need for Network Upgrades on the EPE and Southern New Mexico transmission systems. This amount of generation resulted in less than 230 MVA flowing across the Amrad autotransformer under normal or contingency conditions. February 22, TRC

6 The post-project voltage analysis results showed that switching of the existing 80 MVAR shunt reactor at Amrad would violate the criteria limits. For the line switching purposes it is recommended to replace the 80 MVAR shunt reactor at Amrad with the 50 MVAR shunt reactor; The Amrad shunt reactor replacement is a Network Upgrade. Cost Estimates The estimated total cost of the ART320W ERIS interconnection is $6,390,000. This breaks down to $1,288,000 for the total Transmission Provider Interconnection Facilities Cost 1 for the ART320W interconnection to the Artesia/Eddy County 345 kv substation and $5,102,000 for Network Upgrades Cost 2. The Generator Interconnection Cost 3 estimates are not included. Conclusion This Energy Resource Interconnection Study, consisting only of Steady State and Stability Analyses, showed that with Network Upgrades in place ART320W can generate up to 231 MW of generation at the Artesia/Eddy County 345 kv station without having an adverse impact on the EPE and Southern New Mexico transmission systems. The ART320W project may request that its Generating Facility deliver its generating output using ERIS using the existing firm or nonfirm capacity of EPE s Transmission System on an as available basis. However, ERIS does not guarantee that transmission service will be available to deliver the generating output of the project when it is placed into service. The estimated interconnection cost for the ART320W project to the Artesia/Eddy County 345 kv station is $1,288,000, while the estimated Network Upgrade cost (Amrad shunt replacement and Artesia/Eddy County generation interconnection facilities) is $5,102,000. The Good faith estimate for the Commercial Operation Date is May Transmission Provider Interconnection Facilities Costs are cost for facilities and equipment owned, controlled, or operated by the Transmission Provider from the Point of Change of Ownership to the POI. The costs for these facilities are paid by the IC and are not subject to transmission credits. Network Upgrades Costs are costs of facilities from the Point of Interconnection outward, paid for by the interconnector but owned and operated by EPE. The costs for these facilities are subject to transmission credits. Generator Interconnection Facilities Costs are costs for facilities and equipment owned and operated by the Interconnection Customer (IC) from its Generating Facility to the Point of Change of Ownership (typically the first dead-end at the POI). The costs for these facilities are paid by the IC and are not subject to transmission credits. February 22, TRC

7 1. Introduction The Interconnection Customer proposed interconnection of 320 MW of generation to the EPE 345 kv transmission system. After the System Impact Study (SIS) was completed, the Interconnection Customer decided to proceed with an ERIS study. The ERIS study is an optional study Interconnection Customers may request to determine the amount of electric output the Generating Facility can deliver to the Transmission Provider s Transmission System using existing firm or nonfirm capacity of the Transmission Provider s Transmission system on as as available basis. ERIS does not guarantee that transmission service will be available when the generation interconnection project is placed into service. The proposed in-service date for the ART320W project is May, Performance Criteria The Study was performed according to WECC, North American Electric Reliability Corporation (NERC) and EPE standards. The EPE local reliability standards can be found in Section 4 of EPE s FERC Form No The steady state analysis was performed by using the GE PSLF Version 17.8 program. 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. All facility loadings, as well as voltages greater than 34.5 kv, were monitored within the El Paso, New Mexico and Arizona control areas. Pre-contingency flows on lines and transformers were required to remain at or below the normal rating, while post-contingency flows on lines and transformers are required to remain at or below the emergency rating. Flows above 100% of an element s rating, either pre- or post-contingency, were considered violations. Post-project voltage criteria violations that either exacerbate or improve an existing pre-project violation are not considered an adverse impact to the system. The performance criteria utilized in qualifying violations in the study area are shown in Table 1-1. February 22, TRC

8 Table 1-1: EPE and New Mexico Performance Criteria Area Conditions Loading Limits EPEC PNM Tri- State Normal Contingency Normal ALIS Contingency N-1 Contingency N-2 Normal ALIS Contingency N-1 Contingency Normal Rating Emergency Rating Voltage (p.u.) Voltage Drop Application kV and above Artesia 345 kv Arroyo 345 kv PST source side Alamo, Sierra Blanca and Van Horn 69kV % 60 kv to 115 kv % Artesia 345kV % Arroyo 345kV PST source side Alamo, Sierra Blanca and Van Horn 69kV % Hidalgo, Luna, or other 345 kv buses Normal Rating kv and above* Emergency Rating Emergency Rating *** 6 %** 46 kv to 115 kv *** 6 %** 230 kv and above *** 10 % 46 kv and above* Normal Rating All buses Emergency Rating Emergency % % % All buses N-2 Rating * Taiban Mesa and Guadalupe 345 kv bus voltage must be between 0.95 and 1.10 p.u. under normal and contingency conditions. ** For PNM buses in southern New Mexico the allowable N-1 voltage drop is 7%. *** Provided operator action can be utilized to adjust voltages back down to 1.05 Tri-State buses in the PNM Service Area (list provided by Tri-State) Tri-State buses in southern and northeastern New Mexico (list provided by Tri-State) February 22, TRC

9 2. Study Methodology 2.1 Assumptions The following assumptions are consistent for all study scenarios unless otherwise noted. This study assumes that all system expansion projects as planned by area utilities by the year under analysis are completed and that any system improvements required by the interconnections senior to the ART320W project are implemented. This study did not analyze any transmission service from the interconnection point to any specific point on the grid for the interconnections senior to the ART320W project. It only determined the Energy Resource Interconnection Service level which does not require any Network Upgrades on the EPE and Southern New Mexico transmission grid other than the upgrades required to interconnect the project. 2.2 Procedure The analyses in this study included Steady State and Stability Analysis, as stated in the Mescalero Ridge Wind Energy Resource Interconnection Study Statement of Work that is included in Appendix A. A description of the procedures used to complete the analyses is presented below Development and Description of Cases 100% peak summer load 2016 WECC power flow cases were used and modified, as listed below, to establish 2016 benchmark cases without the ART320W study interconnection project. In addition, 2016 off-peak cases were created from peak cases at 60% of the peak load, with generation adequately dispatched for that load level, to determine any off-peak violations. In Scenario 1, the Arroyo Phase Shifter was set to MW N-S in the peak and MW N-S in the off-peak cases. In Scenario 2, the Arroyo Phase Shifter was by-passed. In both scenarios, the Eddy County DC tie operational flow was set at 0 MW. February 22, TRC

10 2016 Benchmark Cases: The 2016 benchmark cases included the following existing third party generation: MW of generation (Luna Energy Facility) interconnected at the Luna 345 kv bus and scheduled to the WECC grid MW of generation (Afton CT) interconnected at the Afton 345 kv Substation and scheduled to PNM through the EPE/PNM control area at the West Mesa 345 kv bus MW of generation (Pyramid) interconnected at PNM s Pyramid 115 kv Substation and scheduled to the PNM grid MW of generation (Lordsburg) interconnected at PNM s Lordsburg 115 kv Substation and scheduled to the PNM grid MW of generation (Afton ST) interconnected at the Afton 345 kv Substation and scheduled to PNM MW of generation (MS99W) interconnected on the Luna Springerville 345 kv line 30 miles from Luna and scheduled to the WECC grid MW of generation (DS92S) interconnected on the Diablo-Santa Teresa 115 kv line 5.7 miles from Diablo 115 kv station and scheduled to the WECC grid Post-Project Cases: 2016 post-project cases were created from the benchmark cases described above for two post-project scenarios: - Scenario 1: Arroyo Phase-Shifter in service; - Scenario 2: Arroyo Phase-Shifter by-passed. Scenario 1 Scenario 2 West Mesa West Mesa Arroyo Phase Shifter Arroyo Arroyo February 22, TRC

11 2.2.2 Contingency List Based on the SIS results and engineering judgment, it was chosen to evaluate system performance for only one contingency, loss of Caliente Amrad 345 kv line. This contingency was the most severe as found during the 345 kv Cluster SIS 4, which is posted on the EPE web site. 4 February 22, TRC

12 3. Steady State Power Flow Analysis 3.1 Pre-Project Power Flow Evaluation Peak and off peak base cases were evaluated for overloaded facilities under both normal and contingency conditions prior to the addition of the ART320W project Pre-Project N-0 Flow Violations Power flow study analysis results showed that prior to the addition of the ART320W project no overloaded transmission facilities were present in the El Paso Electric (EPE) and Public Service Company of New Mexico (PNM) areas under non-contingency system conditions Pre-Project N-1 Flow Violations Power flow contingency analysis results showed that prior to the addition of the ART320W project no overloaded transmission facilities were present in the El Paso Electric (EPE) and Public Service Company of New Mexico (PNM) areas for the loss of Amrad-Caliente 345 kv line. 3.2 Post-Project Power Flow Evaluation This section provides a high-level understanding of the ART320W projects impact on the loading of transmission lines and transformers in the Study Area. The analysis was performed under both normal and contingency conditions Post-Project N-0 Power Flow Analysis Power flow study results for the EPE and PNM areas showed that the addition of the 320 MW of generation from the ART320W project to the existing system would not cause any flow violation under non-contingency system conditions Post-Project N-1 Power Flow Analysis Power flow study results for both scenarios showed that the addition of the 320 MW of generation from the ART320W project to the existing system would cause Amrad 345/115 kv transformer to overload for the loss of Amrad-Caliente 345 kv line. In both scenarios, the ART320W output was reduced until this overload was eliminated. The Amrad 345/115 kv transformer loadings for different MW levels are shown in Table 3-1 through Table 3-4. Figure 3.1 shows the maximum flow through the Amrad autotransformer. February 22, TRC

13 Table 3-1: 2016 peak N-1 power flow analysis results Scenario 1 Arroyo Phase-Shifter in service W/O Project With Project Delta ART320W (MW) From Bus kv To Bus kv Ckt ID Area Rating (MVA) % of Emergency Rating Post - Pre Project 320 AMRAD 345 AMRAD AMRAD 345 AMRAD AMRAD 345 AMRAD Table 3-2: 2016 off peak N-1 power flow analysis results Scenario 1 Arroyo Phase-Shifter in service W/O Project With Project Delta ART320W (MW) From Bus kv To Bus kv Ckt ID Area Rating (MVA) % of Emergency Rating Post - Pre Project 320 AMRAD 345 AMRAD AMRAD 345 AMRAD AMRAD 345 AMRAD February 22, TRC

14 Table 3-3: 2016 peak N-1 power flow analysis results Scenario 2 Arroyo Phase-Shifter by-passed W/O Project With Project Delta ART320W (MW) From Bus kv To Bus kv Ckt ID Area Rating (MVA) % of Emergency Rating Post - Pre Project 320 AMRAD 345 AMRAD AMRAD 345 AMRAD AMRAD 345 AMRAD Table 3-4: 2016 off peak N-1 power flow analysis results Scenario 2 Arroyo Phase-Shifter by-passed W/O Project With Project Delta ART320W (MW) From Bus kv To Bus kv Ckt ID Area Rating (MVA) % of Emergency Rating Post - Pre Project 320 AMRAD 345 AMRAD AMRAD 345 AMRAD AMRAD 345 AMRAD February 22, TRC

15 Figure 3-1: 2016 peak N-1 system condition when 231 MW generated at ART320W Amrad 345/115 kv autotransformer for the loss of the Amrad-Caliente 345 kv transmission line February 22, TRC

16 3.3 Power Flow Analysis Conclusion The analysis showed that up to 231 MW, generated by the ART320W project, could be added to the existing system without the need for Network Upgrades on the EPE and Southwestern New Mexico transmission systems, except for the upgrades required to interconnect the ART320W project into the EPE Transmission System. February 22, TRC

17 4. Steady State Voltage Analysis Bus voltages within the Study Area were compared before and after the addition of 231 MW at Artesia/Eddy County station for the loss of Amrad Caliente 345 kv line. The Performance Criterion, shown in Table 1-1, was considered when analyzing bus voltages for violations. The results showed that the operation of ART320W at 231 MW depends on the in-service of the Static VAR Compensator at Amrad due to high voltage issues following the loss of generation and the Amrad-Eddy County 345 kv line essentially single ended at Eddy County. The voltage analysis showed that with the addition of the ART320W project, the existing Amrad 80 MVAR shunt reactor will not be the appropriate size shunt reactor to be switched in and out as necessary. For line switching purposes, it is recommended to replace the 80 MVAR shunt reactor at Amrad with a 50 MVAR shunt reactor. Table 4-1: System VAR reinforcements Location Controlling kv MVAR In Service Shunts ART320W Artesia ART320W Amrad AA100W Amrad The results showed that with the recommended 50 MVAR shunt reactor at Amrad in place, the area transmission network voltage levels stayed within criteria limits and without significant changes from the pre-project voltage levels. February 22, TRC

18 5. Cost Estimates A Facilities Study for the ART320W interconnection to the Artesia/Eddy County 345 kv substation via a 70-mile 345 kv line was completed in January As defined in EPE s Open Access Transmission Tariff (OATT), the 70 mile line qualifies as Generator Interconnection Facility Cost 5. Therefore, ART320W is responsible for paying the total cost to construct this line. The estimated total cost for the ERIS interconnection is $6,390,000. This breaks down to $1,288,000 for the Transmission Provider Interconnection Facilities Cost 6 for the ART320W interconnection to the Artesia/Eddy County 345 kv substation and $5,102,000 for the Network Upgrades Cost 7. Good faith cost estimates have been determined. The cost estimates are in 2012 dollars (no escalation applied). Figure 5-1 shows the ART320W connection to Artesia/Eddy County 345 kv substation and the POI configuration. Figure 5-1: Artesia/Eddy County 345 kv Substation and ART320W POI Configuration Generator Interconnection Facilities Costs are costs for facilities and equipment owned and operated by the Interconnection Customer (IC) from its Generating Facility to the Point of Change of Ownership (typically the first dead-end at the POI). The costs for these facilities are paid by the IC and are not subject to transmission credits. Transmission Provider Interconnection Facilities Costs are cost for facilities and equipment owned, controlled, or operated by the Transmission Provider from the Point of Change of Ownership to the POI. The costs for these facilities are paid by the IC and are not subject to transmission credits. Network Upgrades Costs are costs of facilities from the Point of Interconnection outward, paid for by the interconnector but owned and operated by EPE. The costs for these facilities are subject to transmission credits. February 22, TRC

19 Table 2-1 shows the Transmission Provider Interconnection Facilities cost estimates associated with interconnecting ART320W to the Artesia/Eddy County 345 kv substation. The total Transmission Provider Interconnection Facilities cost for the ART320W interconnection to EPE is $1,288,000. Table 5-1: Transmission Provider Interconnection Facilities Cost Estimate Artesia/Eddy County 345 kv Substation Upgrade The Network Upgrade (facilities from the POI to the transmission system) costs for the ART320W interconnection to the Artesia/Eddy County 345 kv substation are shown in Table 2-2 below. The total Network Upgrade cost for the Artesia/Eddy County 345 kv substation is $3,242,000. Table 5-2: Artesia/Eddy County 345 kv Network Upgrade Cost Estimate Table 5-3 shows the engineering, procurement and construction schedules for the Artesia/Eddy County 345 kv substation. The estimate start date is January 2012 and completion date is May Table 5-3: Artesia/Eddy County 345 kv Substation Schedule February 22, TRC

20 In addition, the Amrad 80MVAR reactor must be replaced with a 50MVAR reactor to accommodate for line and reactor switching. The estimated cost for the Amrad reactor shunt replacement is $1,860,000. This shunt replacement is a Network Upgrade. The total estimated Network Upgrade cost to interconnect the ART320W project into the EPE transmission system is $5,102,000, the sum of the estimated costs shown in Table 5-2 ($3,242,000) and the estimated cost to replace the shunt reactor at Amrad ($1,860,000). Artesia/Eddy County Substation Upgrades Material February 22, TRC

21 6. Stability Analysis Stability analysis was performed for peak and off-peak load conditions to determine if, the ART320W will have any impact on the EPE and Southwestern New Mexico transmission system performance. This analysis evaluated the performance of the system for the entire loss of the project (231 MW). The simulations were conducted using the PSLF power flow and dynamic simulation software, General Electric, Inc. PSLF load flow software package, Version Dynamic stability simulations were conducted for peak and off-peak load conditions with the Projects units on at full capacity and off. 6.1 Dynamic Modeling EPE provided the base cases and dynamic file data base for this part of the study. The Interconnection Customers provided the detailed model data sheets and/or parameter values. The Project was modeled as two generators: - Unit 1 wind generator dispatched at 116 MW; - Unit 2 wind generator dispatched at 115 MW. Detailed PSLF model data for the ART320W units can be found in Appendix C. Table 6-1 shows the models used for the studies. Table 6-1: Generator Models Used for Studies Project Turbine Type Notes PSLF Model ART320W GE 2.5 MW Full Converter Model standard GEWTG MS50.4W Siemens VS 1.8 MW Variable speed, doubly-fed asynchronous generators with rotor-side converter (DFAG) Used PSLF Generic model with default parameters WT3G 6.2 Stability Study Case Development Four study cases were used to simulate Peak and Off-Peak conditions, with and without the Arroyo Phase Shifter in service, and the ART320W project at 231 MW output. 6.3 Stability Analysis Results The stability analysis showed that the EPE and Southwestern New Mexico transmission system remained stable for the loss of the project. The stability plots can be found in Appendix C. February 22, TRC

22 6.4 Stability Analysis Conclusion The study area remains stable for the loss of ART320W. Therefore, the project addition to the system does not pose any concern to system stability performance. February 22, TRC

23 7. Conclusions This ERIS Study, consisting of only Steady State and Stability Analyses, showed that ART320W can deliver up to 231 MW of generation at the Artesia/Eddy County 345 kv station without having an adverse impact on the EPE and Southern New Mexico transmission systems. The estimated total cost for the ART320W Energy Resource Interconnection Service is $6,390,000 and the good faith estimate for the completion date is May February 22, TRC

24 Appendix A Energy Resource Interconnection Study Statement of Work February 22, 2012 Appendix A TRC

25 MESCALERO RIDGE WIND ENERGY RESOURCE INTERCONNECTION SERVICE STUDY REVISED STATEMENT OF WORK All capitalized terms not defined herein shall have the definitions specified in EPE s most current Open Access Transmission Tariff (the OATT ). This Statement of Work is pursuant to the May 5, 2009 CSA between EPE and TRC for additional studies to be conducted. EPE W/O# TS TRC Project # Use PSLF to perform load flow analyses for an Energy Resource Interconnection Service (ERIS) Study (as specified under EPE s OATT) on the EPE and affected utilities in the WECC transmission system ( System ) as follows: 1.1. Post-Project Power Flow Analysis Start with the 345 kv Cluster 2016 pre-project heavy load and light load power flow pre-project cases used in the SIS Re-Study #2 analyses Determine any pre-project violations on the system for the loss of Caliente - Amrad 345 kv line Develop the post project Mescalero Ridge Wind (MRW) generator interconnection heavy load and light load power flow cases by adding the ART320W 320 MW wind project model into the 2016 preproject heavy load and light load power flow cases A list of post project power flow base case scenarios to be studied are shown in Table 1: Year 2016 Heavy Load Case Arroyo PST = MW N-S Eddy County HVDC OFF Senior Queued Projects Table 1: Base Case Scenarios Descriptions Light Load Heavy Load Case Case Arroyo PST = Arroyo PST MW Bypassed N-S Eddy County HVDC OFF Senior Queued Projects Eddy County HVDC OFF Senior Queued Projects Light Load Case Arroyo PST Bypassed Eddy County HVDC OFF Senior Queued Projects ART320W generation will be modeled in the post-project cases as it was modeled in the System Impact Study and dispatched to the TRC Page 1 February 6, 2012

26 1.2. Power Flow Report WECC control areas 14 through 73, thereby not specifying a particular transmission path Determine and document any post-project violations on the system for the loss of Caliente-Amrad 345 kv line, and then lower the ART320W generation until all violations caused by the addition of the ART320W project are removed from the system. The lower generation level value for both scenarios, with Arroyo PST in service and Arroyo PST by-passed, that does not have an adverse impact the on the system will be considered as the ART320W energy resource generation level. Prepare a detailed power flow analysis report including: Executive summary The required Network Upgrades for Energy Resource Interconnection Service Description of the Project load flow analyses Include a non-binding, good faith estimate of cost for the MRW project to interconnect to the EPE transmission system Estimated time frame for interconnection of the project onto the system. 2. Use PSLF to perform stability analyses for an Energy Resource Interconnection Study (ERIS) (as specified under EPE s OATT) on the EPE and affected utilities in the WECC transmission system ( System ) as follows: 2.1. Post-Project Stability Analysis Develop 2016 post-project cases for heavy (100% peak load) and light load (60% of peak load) scenarios, as shown in Table 2. TRC Page 2 February 6, 2012

27 Year 2016 Table 2: Post-Project Stability Analysis Cases Case Descriptions Light Load Heavy Load Case Case Arroyo PST = Arroyo PST MW N- Bypassed S Heavy Load Case Arroyo PST = MW N-S Eddy County HVDC OFF ART320W at 320 MW or identified MW level when no violations. Eddy County HVDC OFF ART320W at 320 MW or identified MW level when no violations. Eddy County HVDC OFF ART320W at 320 MW or identified MW level when no violations. Light Load Case Arroyo PST Bypassed Eddy County HVDC OFF ART320W at 320 MW or identified MW level when no violations Perform stability analysis on post-project scenarios listed in Table 2 by applying contingencies listed in Table 3. Table 3: Post-project Stability Contingencies Fault # Type Location Duration Trip 1 3-Phase ART320W 345 kv 4 cycles Loss of all generation 2.3. Stability Analysis Report Prepare a stability analysis report for the MRW generator to be included in the power flow report that will include: Description of the stability analysis study cases Description of the dynamic data used in the stability analyses Stability analysis results Stability plots 3. Re-Studies: 3.1. If a Re-Study is required to be performed as per Section 7.6 of the LGIP, perform a Re-Study with the withdrawn generator and its required facilities removed from the case(s). EPE will notify TRC as soon as possible if this occurs so that TRC can stop work on the initial study and begin work on the Re-Study As per Section 7.6 of the LGIP, the Re-Study must be completed within 60 calendar days of the Interconnection Customer being notified. Any cost of the Re-Study will be borne by the Interconnection Customer being re-studied. TRC Page 3 February 6, 2012

28 4. Data Required: 4.1. Use power flow and stability cases developed in the SIS Re-Study #2 analyses and modify as needed to perform this ERIS study. 5. Deliverables: 6. Cost: 5.1. Detailed reports as stated in sections 1 and During the Study process, TRC will send EPE a progress report on a regular basis, but no less than once each week. If the Study time appears to exceed the Study time limit as given in EPE s OATT in the Large Generator Interconnection Procedures, TRC will notify EPE in a timely manner and give an estimate of completion of the Study Original and final ERIS base cases, with appropriate EPC change files, will be sent upon completion of Final Report TRC will perform this ERIS on a time and expense basis totaling $13,000. Travel costs are not included in the cost estimate. Table 6 lists the estimated time to complete each task. Table 6: Itemized 345 kv Cluster ERIS Time Frames 345 kv CLUSTER ERIS Item Description Hours Base Case, Project Case and File Prep and 1 Prepare Draw Files 8 2 Contingency Analysis and Determine Limit 28 3 Stability Analysis 6 4 Report Writing & Documentation 25 5 Report Review and Comment 4 6 Management Oversight 2 7 Misc. Project Management 3 8 Misc. Admin Assistance 1 Total Study Time frame to complete the study will be approximately 3 Weeks If the Study appears to have become difficult and, therefore increasing the Study costs, TRC will inform EPE immediately with an estimated increase in cost so that approval can be obtained. TRC Page 4 February 6, 2012

29 7. Billing: TRC will provide a monthly bill showing detailed hours and expenses charged to overall project. TRC will use the following codes for charging the Cluster Generators: ART320W - Mescalero Ridge Wind: TS Once received, EPE will have 30 days to process and send payment. Rates for Employee Classification are attached as Appendix A of this Work Scope. 8. Signatures TRC Engineers, LLC. by: Name: Title: El Paso Electric Company by: Name: Title: TRC Page 5 February 6, 2012

30 Appendix B Stability Plots February 22, 2012 Appendix B TRC

31 ART320W GENERATOR OUTPUTS Generator Terminal Voltage (pu) Time( sec ) a vt ART320W_G a vt ART320W_G Generator Real Power Output (MW) Time( sec ) a pg ART320W_G a pg ART320W_G Generator Reactive Power Output (MVAr) Time( sec ) a qg ART320W_G a qg ART320W_G Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 1 Wed Feb 08 14:29:

32 Rotor Angles (degrees) Time (sec) a ang NEWMN4G a ang LEF_G a ang SJUAN_G a ang RIOGD_G a ang a ang SPR GEN Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 2 Wed Feb 08 14:29:

33 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN4G a vt LEF_G a vt SJUAN_G a vt RIOGD_G a vt a vt SPR GEN Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 3 Wed Feb 08 14:29:

34 Rotor Angles (degrees) Time (sec) a ang NEWMN5G a ang a ang NEWMN4G a ang LEF_S a ang LRDSBGG a ang ROADRUNR-G Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 4 Wed Feb 08 14:29:

35 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN5G a vt a vt NEWMN4G a vt LEF_S a vt LRDSBGG a vt ROADRUNR-G Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 5 Wed Feb 08 14:29:

36 1.20 Bus Voltages (pu) Time (sec) a vbus ARROYO a vbus WESTMESA a vbus CALIENTE a vbus ART320W a vbus ARROYO a vbus NEWMAN Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 6 Wed Feb 08 14:29:

37 62.00 Frequency (Hertz) Time (sec) a fbus ARROYO a fbus WESTMESA a fbus CALIENTE a fbus ART320W a fbus ARROYO a fbus NEWMAN Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 7 Wed Feb 08 14:29:

38 1.20 Bus Voltages (pu) Time (sec) a vbus SAN_JUAN a vbus RIOPUERC a vbug LUNA a vbus AFTON a vbus HIDALGO a vbus AMRAD Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 8 Wed Feb 08 14:29:

39 62.00 Frequency (Hertz) Time (sec) a fbus SAN_JUAN a fbus RIOPUERC a fbug LUNA a fbus AFTON a fbus HIDALGO a fbus AMRAD Off Peak Post-Project Case - Arroyo Phase Shifter in service r001_16op-ap_projloss_w.chf Page 9 Wed Feb 08 14:29:

40 ART320W GENERATOR OUTPUTS Generator Terminal Voltage (pu) Time( sec ) a vt ART320W_G a vt ART320W_G Generator Real Power Output (MW) Time( sec ) a pg ART320W_G a pg ART320W_G Generator Reactive Power Output (MVAr) Time( sec ) a qg ART320W_G a qg ART320W_G Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 1 Wed Feb 08 14:29:

41 Rotor Angles (degrees) Time (sec) a ang NEWMN4G a ang LEF_G a ang SJUAN_G a ang RIOGD_G a ang a ang SPR GEN Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 2 Wed Feb 08 14:29:

42 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN4G a vt LEF_G a vt SJUAN_G a vt RIOGD_G a vt a vt SPR GEN Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 3 Wed Feb 08 14:29:

43 Rotor Angles (degrees) Time (sec) a ang NEWMN5G a ang a ang NEWMN4G a ang LEF_S a ang LRDSBGG a ang ROADRUNR-G Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 4 Wed Feb 08 14:29:

44 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN5G a vt a vt NEWMN4G a vt LEF_S a vt LRDSBGG a vt ROADRUNR-G Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 5 Wed Feb 08 14:29:

45 1.20 Bus Voltages (pu) Time (sec) a vbus ARROYO a vbus WESTMESA a vbus CALIENTE a vbus ART320W a vbus ARROYO a vbus NEWMAN Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 6 Wed Feb 08 14:29:

46 62.00 Frequency (Hertz) Time (sec) a fbus ARROYO a fbus WESTMESA a fbus CALIENTE a fbus ART320W a fbus ARROYO a fbus NEWMAN Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 7 Wed Feb 08 14:29:

47 1.20 Bus Voltages (pu) Time (sec) a vbus SAN_JUAN a vbus RIOPUERC a vbug LUNA a vbus AFTON a vbus HIDALGO a vbus AMRAD Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 8 Wed Feb 08 14:29:

48 62.00 Frequency (Hertz) Time (sec) a fbus SAN_JUAN a fbus RIOPUERC a fbug LUNA a fbus AFTON a fbus HIDALGO a fbus AMRAD Off Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16op-apby_projloss_w.chf Page 9 Wed Feb 08 14:29:

49 ART320W GENERATOR OUTPUTS Generator Terminal Voltage (pu) Time( sec ) a vt ART320W_G a vt ART320W_G Generator Real Power Output (MW) Time( sec ) a pg ART320W_G a pg ART320W_G Generator Reactive Power Output (MVAr) Time( sec ) a qg ART320W_G a qg ART320W_G Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 1 Wed Feb 08 14:28:

50 Rotor Angles (degrees) Time (sec) a ang NEWMN4G a ang LEF_G a ang SJUAN_G a ang RIOGD_G a ang AFTONG a ang SPR GEN Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 2 Wed Feb 08 14:28:

51 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN4G a vt LEF_G a vt SJUAN_G a vt RIOGD_G a vt AFTONG a vt SPR GEN Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 3 Wed Feb 08 14:28:

52 Rotor Angles (degrees) Time (sec) a ang NEWMN5G a ang a ang NEWMN4G a ang LEF_S a ang LRDSBGG a ang ROADRUNR-G Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 4 Wed Feb 08 14:28:

53 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN5G a vt a vt NEWMN4G a vt LEF_S a vt LRDSBGG a vt ROADRUNR-G Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 5 Wed Feb 08 14:28:

54 1.20 Bus Voltages (pu) Time (sec) a vbus ARROYO a vbus WESTMESA a vbus CALIENTE a vbus ART320W a vbus ARROYO a vbus NEWMAN Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 6 Wed Feb 08 14:28:

55 62.00 Frequency (Hertz) Time (sec) a fbus ARROYO a fbus WESTMESA a fbus CALIENTE a fbus ART320W a fbus ARROYO a fbus NEWMAN Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 7 Wed Feb 08 14:28:

56 1.20 Bus Voltages (pu) Time (sec) a vbus SAN_JUAN a vbus RIOPUERC a vbug LUNA a vbus AFTON a vbus HIDALGO a vbus AMRAD Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 8 Wed Feb 08 14:28:

57 62.00 Frequency (Hertz) Time (sec) a fbus SAN_JUAN a fbus RIOPUERC a fbug LUNA a fbus AFTON a fbus HIDALGO a fbus AMRAD Peak Post-Project Case - Arroyo Phase Shifter in service r001_16pk-ap_projloss_w.chf Page 9 Wed Feb 08 14:28:

58 ART320W GENERATOR OUTPUTS Generator Terminal Voltage (pu) Time( sec ) a vt ART320W_G a vt ART320W_G Generator Real Power Output (MW) Time( sec ) a pg ART320W_G a pg ART320W_G Generator Reactive Power Output (MVAr) Time( sec ) a qg ART320W_G a qg ART320W_G Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16pk-apby_projloss_w.chf Page 1 Wed Feb 08 14:28:

59 Rotor Angles (degrees) Time (sec) a ang NEWMN4G a ang LEF_G a ang SJUAN_G a ang RIOGD_G a ang AFTONG a ang SPR GEN Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16pk-apby_projloss_w.chf Page 2 Wed Feb 08 14:28:

60 1.20 Terminal Voltages (pu) Time (sec) a vt NEWMN4G a vt LEF_G a vt SJUAN_G a vt RIOGD_G a vt AFTONG a vt SPR GEN Peak Post-Project Case - Arroyo Phase Shifter by-passed r001_16pk-apby_projloss_w.chf Page 3 Wed Feb 08 14:28: