Executive Summary. Project Overview. Existing System. Study Summary

Transcription

1 APPENDIX A CONNECTION ASSESSMENT

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4 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Executive Summary Project Overview FortisAlberta Inc. (FortisAlberta), in its capacity as the legal owner of distribution facilities (DFO), has submitted a system access service request (SASR) to the Alberta Electric System Operator (AESO), to reliably serve industrial load growth in the Town of Edson area. The SASR includes a request for a Rate DTS, Demand Transmission Service, contract capacity of 18 MW and a request for transmission development in the Town of Edson area (collectively, the Project). Specifically, the DFO requested a new point-of-delivery (POD) substation with one 138/6 kv transformer to serve new and existing loads at the Kinder Morgan Edson pump station terminal. The scheduled in-service date for the Project is February 1, This report presents the system performance studies undertaken to assess the impact of the Project on the Alberta interconnected electric system (AIES). Existing System Geographically, the Project is located in the AESO planning area of Hinton/Edson (Area 29), which is part of the AESO Central Region. The Hinton/Edson area (Area 29) is surrounded by the Wabamun (Area 40), Swan Hills (Area 26), Fox Creek (Area 24), Grande Cache (Area 22) and Drayton Valley (Area 30) planning areas. From a transmission system perspective, the Hinton/Edson area consists primarily of 138 kv and 69 kv transmission systems. The Hinton/Edson area is connected to adjacent planning areas by the two 240 kv transmission lines 973L and 974L and by the three 138 kv transmission lines 854L, 744L, and 202L. There are no existing transmission constraints in the study area. Study Summary Study Area for the Project The study area for the Project consists of Hinton/Edson (Area 29) and Drayton Valley (Area 30), including the tie lines that connect these two planning areas to the rest of the AIES (i.e., the tie lines include the four 138 kv transmission lines 672L, 834L, 854L, 744L and the three 240 kv transmission lines 973L, 974L and 995L). All transmission facilities within the study area were studied and monitored to assess the impact of the Project on the AIES, including any violations of the Reliability Criteria (as defined in Section.1). Studies Performed for the Project Power flow analysis was performed for the 2017 winter peak (WP) pre-project scenario, and the 2017 WP and 2018 summer peak (SP) post-project scenarios. Voltage stability analysis was performed for the 2017 WP and 2018 SP post-project scenarios. Results of the pre-project Studies Under Category A conditions and Category B contingency conditions, no Reliability Criteria violations were observed for the 2017 WP scenario. AltaLink Page I August 2016

5 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Connection Alternatives Examined for the Project FortisAlberta, as the DFO, examined and ruled out the use of distribution solutions to serve the new and existing loads in the Town of Edson area. This report examines five transmission alternatives to meet the DFO s request for system access service. Alternative 1: Modify the existing Edson 58S substation, including adding a 25 kv feeder breaker. Alternative 1 would also require 11 km of new 25 kv distribution feeders along with additional upgrades to the distribution system. Alternative 2: Add a new POD substation, to be named Hornbeck 345S substation, and add approximately 2 km of new 138 kv circuit to connect the Hornbeck 345S substation to the existing 138 kv transmission line 854L with an in/out connection configuration. The Hornbeck 345S substation would include two 138 kv circuit breakers, one 138/6 kv transformer, and other associated equipment. Alternative 3: Add a new POD substation, to be named Hornbeck 345S substation, and add approximately 1 km of new 138 kv circuit to connect the Hornbeck 345S substation to the existing 138 kv transmission line 745L with an in/out connection configuration. The Hornbeck 345S substation would include two 138 kv circuit breakers, one 138/6 kv transformer, and other associated equipment. Alternative 4: Upgrade the existing Marlboro 348S substation by adding a new 138/25 kv transformer and associated equipment, and modify the connection configuration from T-tap to an in/out connection configuration by adding approximately 11 km of new 138 kv circuit. Alternative 5: Upgrade the existing Edson 58S substation, including adding a new 138/25 kv transformer. Connection Alternatives Selected for Further Examination Alternative 1 and Alternative 3 were selected for further study. Both Alternative 2 and Alternative 4 involve additional transmission facility development and hence, additional cost compared to Alternative 1 and Alternative 3. Alternatives 2 and 4 were not selected for further study. The DFO determined that Alternative 5 was not technically feasible due to space constraints; therefore, Alternative 5 was not selected for further study. Results of the post-project Studies Alternative 1 Under Category A conditions and Category B contingency conditions, no Reliability Criteria violations were observed for any of the post-project scenarios. Alternative 3 Under Category A conditions and Category B contingency conditions, no Reliability Criteria violations were observed for any of the post-project scenarios. Conclusions and Recommendation Based on the study results, both Alternative 1 and Alternative 3 are technically viable. The studies show that the connection of the Project using Alternative 1 or Alternative 3 would not adversely impact the performance of the AIES. Cost estimates prepared by the TFO and DFO indicate that Alternative 3 has a lower estimated cost than Alternative 1. While both Alternative 1 and Alternative 3 are technically viable, Alternative 3 is the preferred alternative based on cost. AltaLink Page II August 2016

6 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation It is recommended to proceed with the Project using Alternative 3 (adding the new Hornbeck 345S substation) as the preferred option to respond to the DFO s request for system access service. AltaLink Page III August 2016

7 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Contents Executive Summary... I 1. Introduction Project Project Overview Load Component Generation Component Study Scope Study Objectives Study Area Studies Performed Report Overview Criteria, System Data, and Study Assumptions Criteria, Standards, and Requirements Transmission Planning Standards and Reliability Criteria Authoritative Documents (ADs) Study Scenarios Load and Generation Assumptions Load Assumptions Generation Assumptions Intertie Flow and HVDC Assumptions System Projects Customer Connection Projects Facility Ratings and Shunt Elements Voltage Profile Assumptions Study Methodology Connection Studies Carried Out Power Flow Analysis Contingencies Studied Voltage Stability Analysis Contingencies Studied Pre-Project System Assessment Pre-Project Power Flow Analysis Scenario 1: 2017 Winter Peak Connection Alternatives Overview Connection Alternatives Identified Connection Alternatives Selected for Further Studies Connection Alternatives Not Selected for Further Studies Technical Analysis of the Connection Alternatives Power Flow Alternative Scenario 2: 2017 Winter Peak Scenario 3: 2018 Summer Peak Alternative Scenario 2: 2017 Winter Peak Scenario 3: 2018 Summer Peak Voltage Stability Alternative AltaLink Page IV August 2016

8 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Scenario 2: 2017 Winter Peak Scenario 3: 2018 Summer Peak Alternative Scenario 2: 2017 Winter Peak Scenario 3: 2018 Summer Peak Results Summary Project Interdependencies Conclusion and Recommendation AltaLink Page V August 2016

9 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Attachments Attachment A Attachment B Attachment C Attachment D Attachment E Pre-Project Power Flow Diagrams Alternative 1: Post-Project Power Flow Diagrams Alternative 3: Post-Project Power Flow Diagrams Alternative 1: Post-Project Voltage Stability Diagrams Alternative 3: Post-Project Voltage Stability Diagrams Figures Figure 1-1: Existing Study Area Transmission System... 3 Figure 5-1: Alternative 2 New Substation with In/Out Connection to 854L Figure 5-2: Alternative 3 New Substation with In/Out Connection to 745L Tables Table -1: Post Contingency Voltage Deviation Guidelines... 6 Table -1: List of the Connection Study Scenarios... 6 Table -1: Forecast Area Load (2014 LTO at Alberta Internal Load Peak)... 6 Table -2: Local Generation (MW) in the Study Cases... 7 Table -1: Summary of Customer Connection Assumptions... 7 Table 2.6-1: Summary of Transmission Line Ratings in the Study Area (MVA on Voltage Class Bases)... 8 Table 2.6-2: Summary of Key Transformer Ratings in the Study Area... 8 Table 2.6-3: Summary of Shunt Elements in the Study Area... 9 Table 2.7-1: Summary of Voltage Operating Ranges at Key Nodes in the Study Area... 9 Table 3.1-1: Summary of Studies Performed Table -1: Overview of Pre-Project Study Results Table -2: Overview of Pre-Project Study Results Table 6.1-1: Overview of Post-Project Studies Results Table 6.2-1: Scenario 2: 2017 WP Voltage stability analysis results (Minimum transfer = 16.9 MW) Table 6.2-2: Scenario: 2018 SP Voltage stability analysis results (Minimum transfer = 16.1 MW) Table 6.2-3: Scenario: 2017 WP Voltage stability analysis results (Minimum transfer = 16.9 MW) Table 6.2-4: Scenario: 2018 SP Voltage stability analysis results (Minimum transfer = 16.1 MW) AltaLink Page VI August 2016

10 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 1. Introduction This engineering study report (ESR) presents the results of the studies conducted to assess the impact of the Project (as defined below) on the performance of the Alberta interconnected electric system (AIES) Project Project Overview FortisAlberta Inc. (FortisAlberta), in its capacity as the legal owner of distribution facilities (DFO), has submitted a system access service request (SASR) to the Alberta Electric System Operator (AESO) to reliably serve industrial load growth in the Town of Edson area. The SASR includes a request for a Rate DTS, Demand Transmission Service, contract capacity of 18 MW and a request for transmission development in the Town of Edson area (collectively, the Project). Specifically, the DFO requested a new point-of-delivery (POD) substation with one 138/6 kv transformer to serve new and existing loads at the Kinder Morgan Edson pump station terminal. The scheduled in-service date for the Project is February 1, Load Component The DFO-requested DTS contract capacity for system access service is 18.0 MW, which includes 13 MW of new industrial load and 5 MW of industrial load transferred from Edson 58S Substation. This connection assessment will assume a 0.9 lagging power factor (pf) for the load associated with the Project Generation Component There is no generation component associated with the Project Study Scope 1.. Study Objectives The objective of this study is as follows: Assess the impact of the Project on the performance of the AIES. Identify any violations of the relevant criteria, standards, or requirements of the AESO both pre-project and post-project. Recommend mitigation measures, if required, to enable the reliable connection of the Project to the AIES. AltaLink Page 1 August 2016

11 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 1.. Study Area Study Area Description Geographically, the Project is located in the AESO planning area of Hinton/Edson (Area 29), which is part of the AESO Central region. The Hinton/Edson area (Area 29) is surrounded by the Wabamun (Area 40), Swan Hills (Area 26), Fox Creek (Area 24), Grande Cache (Area 22) and Drayton Valley (Area 30) planning areas. From a transmission system perspective, Hinton/Edson area consists primarily of 138 kv and 69 kv transmission systems. The Hinton/Edson area is connected to adjacent planning areas by the two 240 kv transmission lines 973L and 974L and by the three 138 kv transmission lines 854L, 744L, and 202L. The study area for the Project consists of the AESO planning areas of Hinton/Edson (Area 29) and Drayton Valley (Area 30), including the tie lines connecting these two planning areas to the rest of the AIES (i.e., the tie lines include the four 138 kv transmission lines 672L, 834L, 854L, 744L and the three 240 kv transmission lines 973L, 974L and 995L that connect the Hinton/Edson and Drayton Valley areas to the rest of the AIES). All transmission facilities within the study area were studied and monitored to assess the impact of the Project on the AIES, including any violations of the Reliability Criteria (as defined in Section.1). The existing transmission system in the study area is shown in Figure 1-1. AltaLink Page 2 August 2016

12 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Figure 1-1: Existing Study Area Transmission System 24 - Fox Creek 26 - Swan Hills 29 - Hinton / Edson DALEHURST 975S COLD CREEK 602S 615L WATSON CREEK 104S 762L MOUNTAIN COALOBED 411S CARDINAL RIVER 302S 742AL MANALTA COAL GREGG RIVER 476S 745L CHEVIOT 101S 745A1L Weldwood #1 (WWD1) MARLBORO 348S 745AL COALSPUR 426S 501L FICKLE LAKE 406S 847L CADOMIN 983S 685L (to 501CL Benbow 397S) DEER HILL 1012S 743L 740L 854L 854AL 30 - Drayton Valley 740L BICKERDIKE 39S COAL VALLEY 527S Talisman Edson (TLM2) 740AL 671L WEST PEMBINA 477S 844L BRAZEAU 358S EDSON 58S GULF ROBB 414S PINEDALE 207S 890L 202L 841L 801AL ELK RIVER 445S 801L 828L T.M.P.L. NITON 228S PETRO CANADA BRAZEAU RIVER 489S BRAZEAU RUBBER DAM 3E 973L/974L (to Sundance 310P) CYNTHIA 178S PADDLE RIVER 106S 801L 202AL BRAZEAU OUTLET WORKS 294S 744L (to Entwistle 235S) 202L BRAZEAU 62S Entwistle 672L (to WEST PEMBINA 359S Brazeau Hydro (BRA) G1-G Wabamun LODGEPOLE 61S 836L 235S) 673L VIOLET GROVE 283S Benalto 995L (to 17S) 34 - Abraham Lake 38 - Caroline 744AL This diagram contains a simplified version of the system configuration. Technical detail has been simplified for illustration purposes. It does not indicate geographical locations of facilities. 922L/926L (to Sundance 310P) 922L/926L (to MOON LAKE 131S Drayton Valley (DV1) 835AL 995AL Benalto 17S) Genesee 330P) 1325L (to Langdon 102S) 835L BUCK LAKE 454S BuckLake (PW01) WILLESDENGREEN 68S 1325L (to Gas Generator Hydro Generator Other Generator 69 or 72 kv Substation 138 or 144 kv Substation 240 kv Substation 500 kv Substation Keephills 190L/930L 320P) (to KEYSTONE 384S 190L/930L (to Benalto 17S) 31 - Wetaskiwin 69/72 kv 69/138 kv Double Circuit 138/144 kv 240 kv 240 kv Double Circuit 500 kv P1460 Project Area AESO Planning Areas Currency Date: P1460 Area Transmission System 35 - Red Deer Benalto 922L ( AltaLink Page 3 August 2016

13 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Existing Constraints There are no existing transmission constraints in the study area AESO Long-Term Transmission Plans No system development projects the Hinton/Edson and Drayton Valley areas were modelled. The AESO 2015 Long-term Transmission Plan (2015 LTP) 1 includes the following system developments that are in the vicinity of the study area in the near term (by 2020): 2 Increase 240/144 kv transformer capacity at Little Smoky substation; Add new 240 kv transmission lines from Little Smoky 813S Substation to Fox Creek 741S Substation; Expand Fox Creek 741S Substation to include 240/144 kv transmission facilities; Add new 240 kv transmission lines from Fox Creek 741S Substation to Bickerdike 39S Substation near Edson 58S Substation; Open 144 kv line between Fox Creek 741S Substation and Little Smoky 813S Substation; and Add voltage support at Fox Creek 741S Substation. 1.. Studies Performed The following studies were performed for the pre-project analysis: Power flow analysis The following studies were performed for the post-project analysis: Power flow analysis Voltage stability analysis 1.3. Report Overview The Executive Summary provides a high-level summary of the study and its conclusions. Section 1 introduces this engineering study report. Section 2 describes the reliability criteria, system data, and other study assumptions used in this study. Section 3 describes the methodology used for this study. Section 4 discusses the pre-project assessment of the system. Section 5 presents all the connection alternatives contemplated. Section 6 provides a technical analysis of the connection alternatives considered for further study. Section 7 presents any dependencies the Project may have on other AESO plans to expand or enhance the transmission system. Section 8 presents the conclusions and recommendations of this study. 1 The 2015 LTP document is available on the AESO website. 2 The 2015 LTP identifies the near-term transmission developments in the Fox Creek-Valley View subregion on page 51. AltaLink Page 4 August 2016

14 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 2. Criteria, System Data, and Study Assumptions. Criteria, Standards, and Requirements.1. Transmission Planning Standards and Reliability Criteria The Transmission Planning (TPL) Standards, which are included in the Alberta Reliability Standards, and the AESO s Transmission Planning Criteria Basis and Assumptions 3 (collectively, the Reliability Criteria) were applied to evaluate system performance under Category A system conditions (i.e., all elements in-service) and following Category B contingencies (i.e., single element outage), prior to and following the studied alternatives. Below is a summary of Category A and Category B system conditions. Category A, often referred to as the N-0 condition, represents a normal system with no contingencies and all facilities in service. Under this condition, the system must be able to supply all firm load and firm transfers to other areas. All equipment must operate within its applicable rating, voltages must be within their applicable range, and the system must be stable with no cascading outages. Category B events, often referred to as an N-1 or N-G-1 with the most critical generator out of service, result in the loss of any single specified system element under specified fault conditions with normal clearing. These elements include a generator, a transmission circuit, a transformer or a single pole of a DC transmission line. The acceptable impact on the system is the same as Category A. Planned or controlled interruptions of electric supply to radial customers or some local network customers, connected to or supplied by the faulted element or by the affected area, may occur in certain areas without impacting the overall reliability of the interconnected transmission systems. To prepare for the next contingency, system adjustments are permitted, including curtailments of contracted firm (non-recallable reserved) transmission service electric power transfers. The TPL standards, TPL-001-AB-0 and TPL-002-AB-0, have referenced Applicable Ratings when specifying the required system performance under Category A and Category B events. For the purpose of applying the TPL standards to the studies documented in this report, Applicable Ratings are defined as follows: Seasonal continuous thermal rating of the line s loading limits. Highest specified loading limits for transformers. For Category A conditions: Voltage range under normal operating condition per AESO Information Document ID# RS, General Operating Practices - Voltage Control, which relates to Section 30 of the ISO rules, Maintaining Network Voltage. For the busses not listed in ID# RS, Table 2-1 in the Transmission Planning Criteria Basis and Assumptions applies. For Category B conditions: The extreme voltage range values per Table 2-1 in the Transmission Planning Criteria Basis and Assumptions. Desired post-contingency voltage change limits for three defined post event timeframes as provided in Table Filed under a separate cover AltaLink Page 5 August 2016

15 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Table -1: Post Contingency Voltage Deviation Guidelines Time Period Parameter and reference point Voltage deviation from steady state at POD low voltage bus Post Transient (up to 30 sec) Post Auto Control (30 sec to 5 min) Post Manual Control (Steady State) ±10% ±7% ±5%.2. Authoritative Documents (ADs) AESO Information document ID# RS, was applied to establish system normal (i.e., pre-contingency) voltage profiles in the study area and its vicinity. The TCM Rule was followed to assess any criteria violations identified as a result of the connection studies.. Study Scenarios Table -1 provides a list of the study scenarios. This connection assessment will assume a 0.9 lagging power factor for the load associated with the Project. Table -1: List of the Connection Study Scenarios Scenario Year/Season Load Condition Project Load (MW) Project Generation (MW) System Generation Dispatch Conditions WP Pre-Project 0 0 Market dispatch WP Post-Project 18 0 Market dispatch SP Post-Project 18 0 Market dispatch. Load and Generation Assumptions.1. Load Assumptions The study area load forecasts used for this connection study are shown in Table -1, and are based on the AESO 2014 Long-term Outlook (2014 LTO). Table -1: Forecast Area Load (2014 LTO at Alberta Internal Load Peak) Area Name Season Forecast Peak Load (MW) Hinton/Edson Drayton Valley Alberta Internal Load w/o Losses 2017 WP SP WP SP WP 12, SP 12,017.4 AltaLink Page 6 August 2016

16 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation.2. Generation Assumptions The generation conditions for this connection assessment are described in Table -2. The Weldwood Generator unit #2 connected to Cold Creek 602S substation, is considered to be the critical generating unit for the purpose of the studies, and is assumed to be offline for the power flow and voltage stability analyses. Table -2: Local Generation (MW) in the Study Cases Existing /Future Existing Unit Name 602SG1 (Weldwood 1) 602SG2 (Weldwood 2) 58SG1 (Edson 1) Bus Number Area Pmax (MW) 2017 WP Unit Net Generation* (MW) 2018 SP Unit Net Generation (MW) *Unit Net Generation refers to Gross Generating unit MW output less Unit Service Load..3. Intertie Flow and HVDC Assumptions The Alberta-BC, Alberta-Montana, and Alberta-Saskatchewan intertie points are deemed to be too far away to have any material impact on the connection assessment for the Project. Therefore, the intertie flows were dispatched the same as in the AESO s base cases. The Western Alberta Transmission HVDC Line (WATL) and the Eastern Alberta Transmission HVDC Line (EATL) assumptions were expected to have minimal impact for the connection studies. Therefore, HVDC assumptions were kept consistent with that in the AESO planning base cases and not adjusted for this study.. System Projects No system projects were included in the study scenarios.. Customer Connection Projects The list of customer projects included in the study is shown in Table -1. Table -1: Summary of Customer Connection Assumptions Planning Area Queue Position* Planned In-Service Date Project Name Project # Gen (MW) Load (MW) Included/Excluded from Studies** 29 N/A In service Fortis Deer Hill 1012S substation Included Aug ATCO Jasper Interconnection Project Capacity Increase Included * Per the AESO Connection Queue posted in June ** These projects are dispatched per the load and generation levels set out in Section 1 and Section.2. AltaLink Page 7 August 2016

17 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 2.6. Facility Ratings and Shunt Elements The Transmission Facility Owner (TFO) provided the ratings for the existing transmission lines (Table 2.6-1) and the existing key transformers (Table 2.6-2) in the study area. Table 2.6-1: Summary of Transmission Line Ratings in the Study Area (MVA on Voltage Class Bases) Line ID Line Description Voltage Class (kv) Nominal Rating (MVA) Short-term * Rating (MVA) Summer Winter Summer Winter 615L Cold Creek 602S Watson Creek 104S L Bickerdike 39S Cold Creek 602S L Bickerdike 39S Edson 58S L Bickerdike 39S Cold Creek 602S L Bickerdike 39S Coalspur 426S L Bickerdike 39S Edson 58S OT** 135 OT L Bickerdike 39S Marlboro 348S Tap CT*** 263 CT L Benbow 397S Marlboro 348S Tap OT 201 OT L Edson 58S Cynthia 178S L Fox Creek 347S Benbow 397S L Edson 58S Pinedale 207S L Pinedale 207S Entwistle 235S L Bickerdike 39S Sundance 310P CT 333 CT 499 CT 499 CT 974L Bickerdike 39S Sundance 310P CT 333 CT 499 CT 499 CT * When line loading in post Category B contingency is observed to exceed nominal rating and is less than the shortterm (emergency) rating, it is assumed that AESO and TFO operating practices can manage the constraint within the time requirements of TFO short-term (emergency) rating. ** The limitation factor for the line rating is due to other terminal equipment. *** The limitation factor for the line rating is due to a current transformer. Table 2.6-2: Summary of Key Transformer Ratings in the Study Area Substation Name and Number Transformer ID Transformer Voltages (kv) MVA Rating Bickerdike 39S 39ST1 240/ Bickerdike 39S 39ST2 240/ The details of shunt elements in the Study Area are given in Table Capacitors are the only shunt elements within the Study Area; no reactors or Static VAR Compensators (SVC) are present. AltaLink Page 8 August 2016

18 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Table 2.6-3: Summary of Shunt Elements in the Study Area Substation Name and Number Voltage Class (kv) Number of Switched Shunt Blocks Capacitors Total at Nominal Voltage (MVAr) Status in Study (on or off) 2017WP (MVAr) 2018 SP (MVAr) Cold Creek 602S x 3 MVAr 3 3 (on) 3 (on) Edson 58S x 2 MVAr 2 27 (on) 27 (on) Cynthia 178S x 2 MVAr 2 27 (on) 27 (on) Amoco Brazeau 358S x 2 MVAr 2 21 (on) 21 (on) Brazeau 62S x 33.0 MVAr (off) 0.0 (off) Violet Grove 283S x MVAr (on) 0.0 (off) 2.7. Voltage Profile Assumptions The AESO ID# RS was used to establish system normal (i.e., pre-contingency) voltage profiles for key area busses prior to commencing any studies. Table 2-1 of the Transmission Planning Criteria Basis and Assumptions applies for all the busses not included in the ID# RS. These voltages were utilized to set the voltage profile for the study base cases prior to power flow analysis. The key bus voltages for the study area for the project are shown in Table Table 2.7-1: Summary of Voltage Operating Ranges at Key Nodes in the Study Area Substation Nominal Voltage (kv) Minimum Operating Limit (kv) Desired Range (kv) Maximum Operating Limit (kv) Bickerdike 39S Edson 58S Brazeau 62S Willesden Green 68S AltaLink Page 9 August 2016

19 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 3. Study Methodology The analyses performed in this connection assessment were completed using PTI PSS/E version Connection Studies Carried Out The studies to be carried out for this connection study are identified in Table Table 3.1-1: Summary of Studies Performed Scenario and Condition Project 1460 Load (MW) Generation (MW) System Conditions Power Flow 4 Voltage Stability WP Pre-project 0 0 Category A and Category B X WP Post-Project 18 0 Category A and Category B X X SP Post-Project 18 0 Category A and Category B X X. Power Flow Analysis The purpose of the power flow analysis is to quantify any incremental violations in the study area after the Project is connected. Power flow analysis was completed for all study scenarios to identify thermal overloads or transmission voltage violations as per the Reliability Criteria, and to identify any deviations from the desired limits, shown in Table -1. Transformer tap and switched shunt reactive compensation devices such as shunt capacitors and reactors were locked and continuous shunt devices were enabled when performing the Category B power flow analysis. POD low voltage bus deviations were assessed by first locking all tap changers and area capacitors to identify any post-transient voltage deviations above 10%. Second, tap changers were then allowed to adjust, while shunt reactive compensating devices capacitors remained locked; to determine if any voltage deviations above 7% would occur in the area. Third, all taps and shunt reactive compensating devices were adjusted and voltage deviations above 5% were reported for both the pre-project and post-project networks. 3.. Contingencies Studied Power flow analysis was performed for the Category A condition and all Category B contingencies in the study area, including ties to surrounding areas for all pre- and post-project scenarios. AltaLink Page 10 August 2016

20 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 3.3. Voltage Stability Analysis The objective of the voltage stability analysis is to determine the ability of the network to maintain voltage stability at all the busses in the system under normal and abnormal system conditions. The power-voltage (PV) curve is a representation of voltage change as a result of increased power transfer between two systems. The reported incremental transfers will be to the collapse point. As per the AESO requirements, no assessment based upon other criteria such as minimum voltage was made at the PV minimum transfer. Voltage stability analysis was performed for post-project scenarios. Pre-Project voltage stability analysis would only be performed if the post-project scenarios show voltage stability criteria violations. Voltage stability analysis was performed according to the Western Electricity Coordinating Council (WECC) Voltage Stability Assessment Methodology. WECC voltage stability criteria states, for load areas, post-transient voltage stability is required for the area modeled at a minimum of 105% of the reference load level for system normal conditions (Category A) and for single contingencies (Category B). For this WECC standard, the reference load level is the maximum established planned load. Typically, voltage stability analysis is carried out assuming the worst case scenarios in terms of loading. The voltage stability analysis was performed by increasing load in the study area and by increasing the corresponding generation in the AESO planning are of Wabamun (Area 40) Contingencies Studied Voltage stability analysis was performed for the Category A condition and all Category B contingencies in study area, including ties to surrounding areas for all pre- and post-project scenarios. AltaLink Page 11 August 2016

21 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 4. Pre-Project System Assessment. Pre-Project Power Flow Analysis Table -1 provides an overview of the pre-project power flow analysis and applicable mitigation measures. Condition Table -1: Overview of Pre-Project Study Results Results Scenario Mitigation Measure Contingency Result Category A Not applicable No violations None required 2017 WP Category B All No violations None required.1. Scenario 1: 2017 Winter Peak No Reliability Criteria violations were observed under the Category A conditions. No Reliability Criteria violations were observed under the Category B contingency conditions. The results of the power flow analysis are summarized in Table -2 and are shown in the power flow diagrams in Attachment A. Table -2: Overview of Pre-Project Study Results Contingency Thermal Overloads Voltage Performance N-G- 0: System normal N-G-1: All studied contingencies None Acceptable AltaLink Page 12 August 2016

22 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 5. Connection Alternatives 5.1. Overview Five transmission alternatives were examined to meet the DFO s request for system access service, as detailed in Section Connection Alternatives Identified Below is a description of the developments associated with the transmission alternatives that were examined for the Project. 5 Alternative 1: Modify the Edson 58S substation Alternative 1 involves modifying the existing Edson 58S substation by adding a 25 kv feeder breaker. Alternative 1 would also require 1 km of new 25 kv distribution feeders along with additional upgrades to the distribution system to maintain reliability. Alternative 2: Hornbeck 345S substation connected to 138 kv transmission line 854L Alternative 2 involves the addition of a POD substation, named Hornbeck 345S. In this alternative, Hornbeck 345S substation would be connected to the existing 138 kv transmission line 854L by adding 2 km of 138 kv circuit to create an in/out connection configuration. The Hornbeck 345S substation would include two 138 kv circuit breakers, one 138/6 kv LTC transformer with a minimum transformation capacity of 20 MVA, and other associated equipment. The configuration of Alternative 2 is shown in Figure These alternatives reflect more up to date engineering design than the alternatives identified in the Fortis Need for Development, New Edson Area Load Addition Transmission Facility Upgrades, which is filed under a separate cover. AltaLink Page 13 August 2016

23 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Figure 5-1: Alternative 2 New Substation with In/Out Connection to 854L 854L Bus 830 MARLBTAP 854L 1150L Bus 472 Hornbeck 345S Bus 88 BICKERD7 Bus 910 OBED TAP 138/6 kv 15/20/25 MVA 345SD1 745L 345ST1 BUS 4725 HORNBECK9 Bickerdike 39S Alternative 3: Hornbeck 345S substation connected to transmission line 745L Alternative 3 involves the addition of a POD substation, named Hornbeck 345S. In this alternative, Hornbeck 345S substation would be connected to the existing 138 kv transmission line 745L via 1 km of new 138 kv transmission line to create an in/out configuration. The Hornbeck 345S substation would include two 138 kv circuit breakers, one 138/6 kv LTC transformer with a minimum transformation capacity of 20 MVA, and other associated equipment. The configuration of Alternative 3 is shown in Figure 5-2. AltaLink Page 14 August 2016

24 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Figure 5-2: Alternative 3 New Substation with In/Out Connection to 745L Bus 830 MARLBTAP Bus 910 OBED TAP 745L 854L 745L 1150L Bus 88 BICKERD7 Bickerdike 39S Bus 472 Hornbeck 345S 138/6 kv 15/20/25 MVA 345SD1 345ST1 BUS 4725 HORNBECK9 Alternative 4: Upgrade the Marlboro 348S substation Alternative 4 involves upgrading the existing Marlboro 348S substation to provide 25 kv service by adding a 138/25 kv 25 MVA LTC transformer and associated equipment, and adding approximately 11 km of new 138 kv circuit to change the existing T-tap connection to the 138 kv transmission line 854L to an in/out connection configuration. Alternative 5: Upgrade the Edson 58S Substation Alternative 5 involves upgrading the existing Edson 58S substation by adding a 138/25 kv 25 MVA LTC transformer and associated equipment. The DFO determined that constructing the additional distribution feeder egress cables from a third transformer would not be feasible due to space constraints. 5.. Connection Alternatives Selected for Further Studies Alternative 1 and Alternative 3 were selected for further study. 5.. Connection Alternatives Not Selected for Further Studies Both Alternative 2 and Alternative 4 involve additional transmission facility development and hence, additional cost, compared to Alternative 1 and Alternative 3. Specifically, Alternative 2 was not selected for further study because the proposed in/out connection configuration would AltaLink Page 15 August 2016

25 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation require 1 km more 138 kv circuit compared to Alternative 3. Alternative 4 was not selected for further study because the scope of transmission facility upgrades required was much larger than Alternative 1 or Alternative 3. The DFO determined that Alternative 5 was not technically feasible due to space constraints; therefore, Alternative 5 was not selected for further study. AltaLink Page 16 August 2016

26 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 6. Technical Analysis of the Connection Alternatives 6.1. Power Flow Table provides an overview of the post-project power flow analysis. Table 6.1-1: Overview of Post-Project Studies Results Alternative Scenario Contingency Thermal Overloads Voltage Performance WP 2018 SP 2017 WP 2018 SP N-G- 0: System normal N-G-1: All studied contingencies N-G- 0: System normal N-G-1: All studied contingencies N-G- 0: System normal N-G-1: All studied contingencies N-G- 0: System normal N-G-1: All studied contingencies None Acceptable Alternative 1 The following is a summary of the power flow analysis conducted for Alternative 1. Power flow diagrams are provided in Attachment B Scenario 2: 2017 Winter Peak No Reliability Criteria violations were observed under Category A conditions or Category B contingency conditions Scenario 3: 2018 Summer Peak No Reliability Criteria violations were observed under Category A conditions or Category B contingency conditions Alternative 3 The following is a summary of the power flow analysis conducted for Alternative 3. Power flow diagrams are provided in Attachment C Scenario 2: 2017 Winter Peak No Reliability Criteria violations were observed under Category A conditions or Category B contingency conditions. AltaLink Page 17 August 2016

27 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Scenario 3: 2018 Summer Peak No Reliability Criteria violations were observed under Category A conditions or Category B contingency conditions Voltage Stability Voltage stability analysis was conducted using the 2017 WP and 2018 SP post-project scenarios to investigate the system active power margins after the Project under Category A conditions and Category B contingency conditions. 6.. Alternative 1 The following is a summary of the voltage stability analysis conducted for Alternative 1. Voltage stability diagrams are provided in Attachment D Scenario 2: 2017 Winter Peak Voltage stability analysis was performed for the 2017 WP scenario. The reference load level for the Hinton/Edson area and Drayton Valley area (AESO Planning Areas 29 and 30) is MW. The minimum incremental load transfer for the Category B contingencies is 5.0% of the reference load or 16.9 MW to meet the voltage stability criteria (0.05 x MW = 16.9 MW). Table summarizes the voltage stability results for Category A and the worst five (5) Category B contingencies for voltage stability transfer margins. The voltage stability margin is met for all studied conditions. Table 6.2-1: Scenario 2: 2017 WP Voltage stability analysis results (Minimum transfer = 16.9 MW) Contingency From To Maximum incremental transfer (MW) Meets 105% transfer criteria? N-G-0 System Normal Yes 973L Sundance 310P Bickerdike 39S Yes 62ST5 Brazeau Plant 62S 240 kv to 138 kv transformer T Yes 104ST2 Watson Creek 104S 138 kv to 69 kv transformer T Yes 39ST1 Bickerdike 39S 240 kv to 138 kv transformer T Yes 745L Cold Creek 602S Bickerdike 39S Yes Scenario 3: 2018 Summer Peak Voltage stability analysis was performed for the 2018 SP scenario. The reference load level for Hinton/Edson (Area 29) and Drayton Valley (Area 30) is 32 MW. The minimum incremental load transfer for the Category B contingencies is 5.0% of the reference load or 16.1 MW to meet the voltage stability criteria (0.05 x 32 MW = 16.1 MW). Table summarizes the voltage stability results for Category A and the worst five (5) Category B contingencies for voltage stability transfer margins. The voltage stability margin is met for all studied conditions. AltaLink Page 18 August 2016

28 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Table 6.2-2: Scenario: 2018 SP Voltage stability analysis results (Minimum transfer = 16.1 MW) Contingency From To Maximum incremental transfer (MW) Meets 105% transfer criteria? N-G System Normal Yes 973L Sundance 310P Bickerdike 39S Yes 62ST5 Brazeau Plant 62S 240 kv to 138 kv transformer T Yes 104ST2 Watson Creek 104S 138 kv to 69 kv transformer T Yes 745L Cold Creek 602S Bickerdike 39S Yes 39ST1 Bickerdike 39S 240 kv to 138 kv transformer T Yes 6.. Alternative 3 The following is a summary of the voltage stability analysis conducted for Alternative 3. Voltage stability diagrams are provided in Attachment E Scenario 2: 2017 Winter Peak Voltage stability analysis was performed for the 2017 WP scenario. The reference load level for Hinton/Edson (Area 29) and Drayton Valley (Area 30) is MW. The minimum incremental load transfer for the Category B contingencies is 5.0% of the reference load or 16.9 MW to meet the voltage stability criteria (0.05 x MW = 16.9 MW). Table summarizes the voltage stability results for Category A and the worst five (5) Category B contingencies for voltage stability transfer margins. The voltage stability margin is met for all studied conditions. Table 6.2-3: Scenario: 2017 WP Voltage stability analysis results (Minimum transfer = 16.9 MW) Contingency From To Maximum incremental transfer (MW) Meets 105% transfer criteria? N-G System Normal Yes 1150L Bickerdike 39S Hornbeck 345S Yes 973L Sundance 310P Bickerdike 39S Yes 62ST5 Brazeau Plant 62S 240 kv to 138 kv transformer T Yes 104ST2 Watson Creek 104S 138 kv to 69 kv transformer T Yes 39ST1 Bickerdike 39S 240 kv to 138 kv transformer T Yes Scenario 3: 2018 Summer Peak Voltage stability analysis was performed for the 2018 SP scenario. The reference load level for Hinton/Edson (Area 29) and Drayton Valley (Area 30) is 32 MW. The minimum incremental load transfer for the Category B contingencies is 5.0% of the reference load or 16.1 MW to meet the voltage stability criteria (0.05 x 32 MW = 16.1 MW). Table summarizes the voltage stability results for Category A and the worst five (5) Category B contingencies for voltage stability transfer margins. AltaLink Page 19 August 2016

29 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation The voltage stability margin is met for all studied conditions. Table 6.2-4: Scenario: 2018 SP Voltage stability analysis results (Minimum transfer = 16.1 MW) Contingency From To Maximum incremental transfer (MW) Meets 105% transfer criteria? N-G System Normal Yes 1150L Bickerdike 39S Hornbeck 345S Yes 62ST5 Brazeau Plant 62S 240 kv to 138 kv transformer T Yes 973L Sundance 310P Bickerdike 39S Yes 104ST2 Watson Creek 104S 138 kv to 69 kv transformer T Yes 39ST1 Bickerdike 39S 240 kv to 138 kv transformer T Yes 6.3. Results Summary Power flow results confirm that both Alternative 1 and Alternative 3 are technically feasible. Both alternatives would not cause adverse impact to the AIES under Category A conditions and Category B contingency conditions. Voltage stability analysis results demonstrate that the voltage stability margins in Hinton/Edson (Area 29) and Drayton Valley (Area 30) would continue to meet the AESO requirements should the Project proceed as either Alternative 1 or Alternative 3. Based on the study results, both Alternative 1 and Alternative 3 are technically viable. AltaLink Page 20 August 2016

30 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 7. Project Interdependencies The Project is not dependent on other AESO plans to expand or enhance the transmission system. AltaLink Page 21 August 2016

31 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation 8. Conclusion and Recommendation Based on the study results, both Alternative 1 and Alternative 3 are technically viable. The studies show that the connection of the Project using Alternative 1 or Alternative 3 would not adversely impact the performance of the AIES. Cost estimates 6 prepared by the TFO and DFO indicate that Alternative 3 has a lower estimated cost than Alternative 1. While both Alternative 1 and Alternative 3 are technically viable, Alternative 3 is the preferred alternative based on cost. It is recommended to proceed with the Project using Alternative 3 (adding the new Hornbeck 345S substation) as the preferred option to respond to the DFO s request for system access service. The minimum transformation capacity required for the 138/6 kv transformer at the Hornbeck 345S substation is 20 MVA. 6 Cost estimates are provided under separate cover. AltaLink Page 22 August 2016

32 Connection Engineering Study Report for AUC Application: Hornbeck 345S Substation Attachment A Pre-Project Power Flow Diagrams AltaLink Page 23 August 2016

33 1 423 KEEPHIL KEYSTON S_ P C BRB W PEMBI KEYSTO P C BRA BUCK TAP 135 SUNDANC4 49 KEYSTON ELKRIVE W PEMBI P C BRA CYNTHIA HBOG BRA BICKERD AMOCO BR EDSON ELKRIVTP PINEDAL EDSON BICKERD G.ROBB T OBED TAP FICKL TP MARLBTAP MARLBOR BENBOW BRAZEAU8 154 BRAZEAA9 BRAZ# BRAZEAU EDSON A BRAZ OUT BRAZEAB LODGEPO DALEH TP DEERH MTN COA BRAZEAU BRAZEAU MARLBOR MARLBOR COLD CR7 5.1R R 151 BRAZ# DALEHUR7 995 W.GRN TP 6 25 Fortis New Hornbeck 345S Substation - P1460 SK Tie (Import): -0.1 MW BC and MATL (Import): 33 MW FIGURE A1-1-SYSTEM NORMAL 2017 WINTER PEAK PRE-DEVELOPMENT PRINTED ON MONDAY 05. OCTOBER 2015 Bus - Voltage (kv/pu) Branch - MW/Mvar Equipment - MW/Mvar 100.0%Rate B 1.200OV 0.900UV kv: <= <=69.000<= <= <= >

34 1 423 KEEPHIL KEYSTON S_ P C BRB W PEMBI KEYSTO P C BRA BUCK TAP 135 SUNDANC4 49 KEYSTON ELKRIVE W PEMBI P C BRA CYNTHIA HBOG BRA BICKERD AMOCO BR EDSON ELKRIVTP PINEDAL EDSON BICKERD G.ROBB T OBED TAP FICKL TP MARLBTAP MARLBOR BENBOW BRAZEAU8 154 BRAZEAA9 BRAZ# BRAZEAU EDSON A BRAZ OUT BRAZEAB LODGEPO DALEH TP DEERH MTN COA BRAZEAU BRAZEAU MARLBOR MARLBOR COLD CR7 6.9R R BRAZ# DALEHUR7 995 W.GRN TP 6 25 Fortis New Hornbeck 345S Substation - P1460 SK Tie (Import): -0.1 MW BC and MATL (Import): MW FIGURE A1-2 N-1: BRAZEAU PLANT 62S 240/138 KV T WINTER PEAK PRE-DEVELOPMENT PRINTED ON MONDAY 05. OCTOBER 2015 Bus - Voltage (kv/pu) Branch - MW/Mvar Equipment - MW/Mvar 100.0%Rate B 1.200OV 0.900UV kv: <= <=69.000<= <= <= >