Q137 Generation Interconnection Interconnection Facilities Study Results APS Contract No. 52675 By Arizona Public Service Company Transmission Planning July 28, 2014
Q137 FACILITIES STUDY - TECHNICAL REVIEW TABLE OF CONTENTS Contents 1. Introduction... 3 2. Q137 Interconnection Facilities... 4 3. Cost Estimates... 6 3.1. Summary of Construction Time Estimates at the POI... 8 4. Request For Transmission Service... 9 5. Power Factor Requirements... 9 5.1 Reactive Support... 10 6. System Reinforcements... 10 Page i
ACC ACSS ANPP APS ATC CAISO CAWCD CCVT COD CSP CT EPE ER ERIS FaS FERC FeS GT IC IID IR LADWP LGIA NEC NERC NR NRIS NTUA OASIS OATT PG&E PNM POI PPA PSLF/PSDS/SCSC PST PV RAS RFP SCE SDG&E SIS SLG fault SPS SRP SSVEC SVC SVD SWTC TEP TPIF WAPA WECC List of Acronyms Arizona Corporation Commission Aluminum Conductor Steel Supported Arizona Nuclear Power Project Arizona Public Service Available Transfer Capability California Independent System Operator Corporation Central Arizona Water Conservation District Coupling Capacitor Voltage Transformer Commercial Operation Date Concentrated Solar Power Combustion Turbine or Current Transformer El Paso Electric Energy Resource Energy Resource Interconnection Service Facilities Study Federal Energy Regulatory Commission Feasibility Study Gas Turbine Interconnection Customer Imperial Irrigation District Interconnection Request Los Angeles Department of Water and Power Large Generator Interconnection Agreement Navopache Electric Cooperative North American Electric Reliability Corporation Network Resource Network Resource Interconnection Service Navajo Tribal Utility Authority Open Access Same Time Information System Open Access Transmission Tariff Pacific Gas & Electric Public Service Company of New Mexico Point Of Interconnection Purchase Power Agreement Positive Sequence Load Flow/Positive Sequence Dynamic Simulation/Short-Circuit Saturation Curve Phase-Shifting Transformer Photovoltaic Remedial Action Scheme (also known as SPS) Request for Proposal Southern California Edison Company San Diego Gas & Electric Company System Impact Study Single Line-to-Ground fault Special Protection System (also known as RAS) Salt River Project Sulphur Springs Valley Electric Cooperative, Inc. Static VAR Compensator Static VAR Device Southwest Transmission Cooperative Tucson Electric Power Transmission Provider s Interconnection Facilities Western Area Power Administration Western Electricity Coordinating Council Page ii
1. Introduction Arizona Public Service Company (APS) performed this Generator Interconnection Facilities Study (FaS) in response to a 50 MW solar interconnection request by the Interconnection Customer (IC). The Customer is listed in APS s Active Generator Interconnection Queue as queue number 137 (Q137). The purpose of the study is to provide cost and construction schedule estimates for the facilities needed to interconnect the IC s proposed 50 MW solar generation facility located north of Snowflake, Arizona in Navajo County. APS has retained Utility System Efficiencies (USE) to perform the technical analysis portion of this FaS. The Interconnection Customer submitted an interconnection request to APS, which was accepted on June 7, 2010 and has already completed a System Impact Study. This Project is a FERC jurisdictional large interconnection request. The IC s orginally requested Commercial Operation Date for Q137 was December 1, 2012. The Interconnection Customer submitted a revised requested Commercial Operation Date, as per the Facilities Study Agreement for Q137 for March 1, 2017. The IC s requested date to have the interconnection initially energized in order to take back feed power is December 1, 2016. The projected construction duration for Q137 is 15 months. Due to the original in-service and commercial operation dates not being able to be met, APS will utilize the first available dates as shown in the construction milestones found in table 2 below. Please note that the Commercial Operation Date must be within the seven (7) years of the APS acceptance of the Interconnection Customer s Interconnection Request on June 7, 2010. All reasonable efforts will be used by APS to meet the Interconnection Customer s proposed project dates. The IC has requested interconnection into the Sugarloaf 69kV substation. The Point of Interconnection (POI) for this project will therefore be where the 1.5 miles 69kV line from the IC s generating facility interconnects at the Sugarloaf 69kV substation. The IC has chosen to interconnect with the Energy Resource Interconnection Service option. Delivery of the Q137 output beyond the POI would be on an as-available basis only. The delivery of the Q137 output would be subject to the firm or non-firm transmission capacity that may be available when a Transmission Service Request is made. Figure 1 shows a general depiction of the EHV system around Q137 s proposed POI. The Interconnection Customer will be responsible to construct, own and operate the 69kV line from the Q137 generation station up to the last pole before the APS substation fence, also known as the Point of Change of Ownership. The Interconnection Customer will own all structures on the last pole before the APS substation fence. APS will be responsible for taking the 69kV line from that pole and into the 69kV breaker, shown as Transmission Provider s Interconnection Facilities. Page 3
Figure 1. Transmission System in the Q137 vicinity Approximate circuit length (miles) Cholla-DL-W 21.7 DL-W-Zeniff 9.0 Zeniff-Linden 18.6 Linden-Showlow 16.5 Sugarloaf-Zeniff 20.0 Cholla-Woodruff 16.4 DL-E Snowflake 8.2 DL-E-Bacon 6.0 Bacon-Snowflake 14.0 Snowflake-Showlow 19.4 Sugarloaf-Snowflake 13.0 Q137 Sugarloaf 1.5 Dry Lake-W Cholla 69kV bus 336 ACSR line 64 MVA rating Woodruff Bacon Sugarloaf 69kV bus 795 AA line 108 MVA rating Q137 69kV bus 69kV line 69kV breaker Generator Abitibi Heber 69kv delivery point (Navopache) Zeniff 795 ACSS line 191 MVA rating Snowflake 500/69 kv Dry Lake-E POI Shumway Linden 69kv delivery point (Navopache) Showlow 69kv delivery point (Navopache) Showlow Normal Open Navopache Vernon 69kV line Disclaimer Nothing in this report constitutes an offer of transmission service or confers upon the Interconnection Customer ( IC ) any right to receive transmission service. APS and other interconnected utilities may not have the Available Transmission Capacity to support the interconnection described in this report. It should also be noted that all results for the FAS are highly dependent upon the assumed topology and timing of new projects in the vicinity of the interconnection, which are subject to change. 2. Q137 Interconnection Facilities The facilities required to interconnect the Q137 project consist of the installation of two (2) 69kV breakers in the ring bus currently at the Sugarloaf substation; additional relay equipiment for metering and protection; the addition of one (1) 69kV bay for Q137 at the Sugarloaf substation; the installation of one (1) set of PT s and one (1) set of metering CT s; the installation of one (1) 69kV line drop bay, plus metering and protection equipment; and the installation of fiber optic cable on the line feeding into the APS substation with a minimum of 24 single-mode fibers. The total cost for the facilities required to interconnect the Q137 project is $716,915. Page 4
Figure 2 is a one-line diagram of the proposed configuration and interconnection of Q137 s Project. In Figure 2, the facilities shown in black are the existing facilities. Figure 2 also depicts the Customer s Interconnection Facilities which are shown in green. In Figure 2, the facilities shown in blue are Network Upgrades. Figure 2 also shows a small portion of Transmission Provider s Interconnection Facilities (TPIF), shown in red. This is the portion of the 69kV gen-tie line that is within the Sugarloaf substation fence. APS will own, operate, and maintain the portion of that line from the 69kV bus up to the first structure outside of the substation fence, at which point the IC would pick-up ownership and responsibility for the line. Figure 2. New Q137 Switchyard one-line There is one type of upgrades associated with this Project: Network Upgrades. Network Upgrades only apply to some upgrades to the system at or above 69kV. Network Upgrades do not include Distribution Upgrades. Theses upgrades are defined by FERC as: Distribution Upgrades The additions, modifications, and upgrades to the Transmission Provider s Distribution System required at or beyond the Point of Interconnection to facilitate interconnection of the Small Generating Facility and render the transmission service necessary to Page 5
effect the Interconnection Customer s wholesale sale of electricity in interstate commerce. Distribution Upgrades do not include Interconnection Facilities. Network Upgrades The additions, modifications, and upgrades to the Transmission Provider s Transmission System required at or beyond the point at which the Small Generating Facility Interconnects with the Transmission Provider s Transmission System to accommodate the interconnection with the Small Generating Facility to the Transmission Provider s Transmission System. Network Upgrades do not include Distribution Upgrades. Stand Alone Network Upgrades The Network Upgrades that an Interconnection Customer may construct without affecting day-to-day operations of the Transmission System during their construction. Both the Transmission Provider and the Interconnection Customer must agree as to what constitutes Stand Along Network Upgrades and identify them in Appendix A to the Standard Large Generator Interconnection Agreement. Network Upgrades are typically repaid by APS via transmission service credits over a twenty year period. Any amount remaining at the end of the twenty years, if any, are repaid to the Interconnection Customer, including such interest as defined by FERC. APS estimates the following with regards to Network Upgrades: Install 2 new 69 kv breakers in the existing ring bus at the Sugarloaf substation, as well as additional relays for metering and protection. o One 69 kv breaker in bay #8 o One 69 kv breaker in bay #12 o Metering and protection equipment 3. Cost Estimates The desired in-service date to begin testing for the interconnection facilities is December 1, 2016. The estimated cost of the Q137 interconnection is allocated into two categories, Network Upgrades and Transmission Provider s Interconnection Facilities and is summarized in Table 1 below. Construction schedule estimates are from the date the Interconnection Customer provides written authorization to proceed, provided all interconnection agreements and funding arrangements are in place. Interconnection construction costs and timelines were estimated for Q137 based on the approximate location described above. These good faith non-binding cost estimates are applicable only to the APS system. This study reviewed all capacity, construction, flicker, protection and communications requirements to interconnect this FERC generation project. NERC (North American Reliability Corporation) requires that generation facilities provide a primary and secondary (back-up) communications path for data and control. This study does not specifically address any requirements for the Interconnection Customer Generating Facilities. However, the Interconnection Customer shall comply with all APS requirements for a generator operating in parallel with APS s electrical system. Assumptions: The following assumptions were utilized in compiling the cost estimates for Q137: I) Site Land will not need to be acquired Civil will include grounding, foundations and conduit only Page 6
II) Design Full scope of work attained Engineering and design activities will be performed by contractor Metering inside control house via ION Meter and cost included in solar estimate. Estimate includes (2) 69kV line breakers Once drawing package is IFC, no drawings will need to be updated (i.e. modifications from other construction/maintenance activities which occur following issue of package) III) Construction A mobile transformer will not be needed All substation construction and P&C activities will be performed by APS crew Per diem was added Will need to rent equipment, such as manlift; therefore, add equipment rental costs Account for some personnel going to during construction or possible design. APS construction crew will be comprised of a 4-person crew, working 10 hour days, 4 days per week; no overtime APS P&C crew for wiring will be comprised of a 2-person crew, working 10 hour days, 4 days per week; no overtime III) P&C P&C will stay after the construction crews are done to finished all wiring and will put station in service IV) Exclusions Land cost not included in this estimate Any construction outside of substation wall/fence is not included in this estimate. (i.e. overhead, underground, communications, etc ) Table 1. Cost Estimates for Q137 - POI Equipment Description Network Upgrades Transmission Provider's Interconnection Facilities Q137 Work $381,190 $261,615 Q137 Line Work $ $ 28,000 Communications $ $ 46,110 Remote Relay Upgrades $ $ Permits $ $ Metering $ $ Subtotal $381,190 $335,725 Grand Total $761,915. Page 7
PLEASE NOTE: The cost estimates exclude Interconnection Customer costs associated with obtaining permits, easements or income tax or other tax effect and and the cost associated with any Interconnection Customer-owned equipment required for the interconnection of the generators, including protective relaying and a visible open utility disconnect switch. In addition to the construction costs described above, there will be annual operation and maintenance expenses. The estimated cost of annual operation and maintenance expenses is as follows: Common Equipment/ Line Inspections - $3,000 annually - Two inspections per year - Relay maintenance (estimated at every 4-6 years) - Weed abatement spraying (estimated at 2 times per year) Breaker Maintenance - $6,000 each time for: - Overhaul (estimated once every 6 years) Additional actual costs will be charged for: - Emergency maintenance and repair work such as breaker failure-to-close 3.1. Summary of Construction Time Estimates at the POI The IC s requested date to energize the interconnection facilities to receive back feed power is December 1, 2016. Table 2 is a preliminary design and construction timeline. Table 2 estimates that it will take approximately 14 months in order to site, certificate, design, permit, procure, and construct the required facilities to interconnect the Q137 project; putting the earliest possible date for the IC s project to be energized at 15 months from the date all the appropriate agreements are signed and funded. Due to the original in-service and commercial operation dates not being able to be met, APS will utilize the first available dates as shown in the construction milestones found below. High level interconnection construction cost estimates for the facility interconnection are shown in Table 1. Construction schedule estimates are from the date the Interconnection Customer provides written authorization to proceed, provided all interconnection agreements and funding arrangements are in place. Table 2. Q137 Construction Time Estimates at POI LGIA Milestones This Milestone table represents APS s best effort at targeting a high level construction and In-Service schedule per Interconnection Customer s requested In-Service Date. Please note that the Commercial Operation Date must be within the seven (7) years of the APS acceptance of the Interconnection Customer s Interconnection Request. This Schedule and its projected In-Service Date are subject to change due to potential issues with weather, permitting and other required criteria and activities which may cause unforeseen timing delays. Upon commencement of Project, a construction schedule will be negotiated and adjusted accordingly. This Milestone Table represents APS s Standard Option as defined in 5.1.1 of this LGIA. MILESTONE LGIA Signed & Filed at FERC: Generator interconnect agreement signed and filed at FERC subject to Federal Regulatory requirements. RESPONSIBLE DATE PARTY Both Parties 8/4/2014 Page 8
LGIA Funded: Customer s Submittal of Provision of Security (Article 5.5.3 and Interconnection 8/18/2014 Article 5.6.4). Customer Kick-off Meeting Both Parties 8/27/2014 Notice to Proceed: Customer to provide APS with written authorization to Interconnection 9/1/2014 proceed with design and procurement of materials (Article 5.5.2). Customer APS Engineering: APS begin engineering activities. APS 9/8/2014 Materials: APS begin procurement of materials. APS 1/15/2015 Notice to Proceed with Construction: Customer to provide APS with written Interconnection 7/1/2015 authorization to proceed with construction of facilities (Article 5.6.3). Customer APS Overhead Line Construction: APS to begin construction of Overhead APS 7/15/2015 Line APS Construction: APS begin interconnection substation APS 7/15/2015 construction APS Communications Construction: Complete communications and other APS 9/2/2015 activities required for APS Operating Agreement: APS and Interconnection Customer execute the APS Both Parties 8/7/2015 standard Operating Agreement at least 90 days prior to synchronization Outage Window: APS outage for substation cut-in (Subject to change based on System Conditions) APS 9/1/2015 to 10/1/2015 Installation and Proving Relays: Complete line/relay work for substation cut-in APS 10/22/2015 Metering: Metering installed, tested and released for use Both Parties 10/22/2015 Inspection Test Report Submitted and Acknowledged: Customer to provide APS with written test report when testing and inspection is complete. APS to acknowledge that written test report has been received (Article 2.1) In-Service/Back Feed: APS substation cut-in complete and released to APS Operations for IC to obtain back feed power Initial synchronization: The date upon which the Generating Facility is initially synchronized and upon which Trial Operation begins. Commercial Operation: Interconnection Customer Commercial Operation Date (C.O.D.) Both Parties 10/29/2015 APS 11/5/2015 Both Parties 11/12/2015 Interconnection Customer 12/16/2015 4. Request For Transmission Service Transmission service was not studied in the Facilities Study. Such a request is required to be made through the APS OASIS site to the APS Transmission Services Trading Group and is outside the scope of the generator Interconnection Request study process. 5. Power Factor Requirements The APS Open Access Transmission Tariff (OATT) policy regarding power factor requires all Interconnection Customers, with the exception of wind generators, to maintain an acceptable power factor (typically near unity) at the Point of Interconnection (POI), subject to system conditions. The APS OATT also requires Interconnection Customers to be able to achieve +/- 0.95 power factor at the POI, with the Page 9
maximum full-output Var capability available at all outputs. Furthermore, APS requires Interconnection Customers to have dynamic voltage control (operational time of less than 5 seconds) and maintain the voltage as specified by the transmission operator within the limitation of +/- 0.95 power factor, as long as the Project is online and generating. If the Project s equipment is not capable of this type of response, a dynamic reactive device will be required. APS has the right to disconnect the Project from the power grid if system conditions dictate the need to do so in order to maintain system reliability. The method for determining whether or not the generator meets these requirements is to first record the pre-project POI bus voltage. Next, model the generator with zero reactive capabilities at full output. Any shunt devices are turned off. Two synchronous condensers are added to the case with infinite reactive capability. One is at the terminal bus of the unit regulating the bus voltage to 1.0 pu. The other is one bus away from the POI regulating the POI to the pre-project voltage level. The amount of plant losses can be determined by recording the MVAR flow at the POI and adding that to the sum of the synchronous condenser output. Based on the maximum output of the plant, determine the minimum reactive capabilities required to meet the +/-0.95 power factor range. The sum of the two numbers determines the maximum amount of reactive support the project must provide. 5.1 Reactive Support The project online at 50 MW requires a minimum of +/-16.43 MVAR capability at the POI to meet the +/- 0.95 power factor requirement. The calculated plant losses are 9.1 MVAR. The project must be capable of meeting +/-25.53 MVAR to interconnect of which +/-16.43 MVAR must me dynamic. The losses can be made up by installing static VAR devices. 6. System Reinforcements There are several system protection schemes in the area that dictate when generation must be reduced or tripped. The Q137 will need to be incorporated into those schemes. An operating agreement exists between the owners of WECC recognized paths 50 (Cholla-Pinnacle Peak 345kv(APS)) and 54 (Cornado-Silverking 500kv(SRP)) which includes generation in the area of Northeast Arizona which can be reduced or dropped in certain system operating conditions. The Q137 project would be added to the list in a revised operating agreement. Page 10