APS Deer Valley Facility Phoenix, Arizona June 18, 2015 9 AM -12 PM APS/SRP 2nd Quarter Stakeholder Meeting for Transmission Planning FERC Order 890 SRP Attachment K APS Attachment E APS Deer Valley Facility Phoenix, Arizona June 18, 2015 9 AM -12 PM

Agenda 1. Welcome, Introductions, and Stakeholder Meeting Overview 2. Status of Action Items - 12/18/2014 Joint APS/SRP 4th Quarter Public Planning Meeting 3. Purpose of Today’s meeting – APS Planning 4. Purpose of Today’s meeting – SRP Planning     5. Stakeholder Questions/Comments 6. Action Items

2. Status of Action Items There were no action items captured at the 4th Quarter Stakeholder meeting held on 12/18/2014

3. Purpose of Today’s meeting Per APS’s OATT, APS conducts the 2nd quarter public planning meeting to A) review its current transmission study plan B) provide an opportunity for transmission customers to update their loads, resources and other data that were submitted by September 1, 2014 C) provide an opportunity for stakeholder input on any aspect of the study plan D) review any stakeholder proposals previously submitted to APS for study plan alternatives E) invite submittal of additional stakeholder study plan proposals for review and discussion F) provide updates on APS’s planned transmission projects

3.A. APS’s Study Plan APS has two distinct, but related, transmission study processes NERC Compliance APS’s Annual Planning The difference between the two plans: NERC Compliance: Minimum 2 seasons, 2 discrete years (near and long term); all cases examine P0-P7 (formerly Category A – D) APS’s annual planning: 1 season, 10 consecutive years; N-0 and N-1 Annual plan is used as starting point for NERC Compliance Working on combining TPL assessment and Annual Planning for future years

3.A. 2014 NERC Compliance Studies Peak Load Assessment – Summer NERC STANDARD STUDIES PERFORMED   TPL -001(n-0) Thermal Transient Stability Post Transient 2019 PEAK X MLSC 2024 TPL-002 (n-1) PEAK (Lines, xfmrs, gens) MLSC (Lines, xfmrs, gens) TPL-003 (n-2) Stuck Breaker/Breaker Failure N-1-1 Bus Section TPL-004 (n-xx) Major Substations With/Without Generation Common Corridor

3.A. 2014 NERC Compliance Studies Low Load Assessment NERC STANDARD STUDIES PERFORMED   TPL -001(n-0) Thermal Transient Stability Post Transient Near-Term TO BE DETERMINED X Long-Term TPL-002 (n-1) TRANSMISSION LINE XFMR GENERATION REACTORS TPL-003 (n-2) Stuck Breaker N-1-1 TPL-004 (n-xx) Loss of All Generation Units at a Station Common Corridor

3.A. NERC Compliance Results? APS is fully compliant with NERC Transmission Planning Standards 2015 Progress? Case building complete DYD files being finalized Perform study work starting in July/August

3.A. 2015 NERC Compliance Study Methodology NERC Compliance Studies Cases 2016, 2020 & 2024 Summer Peak Cases Off-peak Case is Low Load and High Import (shoulder case with low generation in the Phoenix Metro Area) 2017 Light Spring case; one case in the near-term High ratio of renewable generation to overall generation on-line Following analyses are conducted: Thermal Post-Transient Short-Circuit Transient Stability

3.A. 2015 NERC Compliance Studies TPL-001-4 combined previous TPL-001 through TPL-004 No longer Category A, B, C, & D Now P0 through P7 Covers all scenarios from N-0 to N-1-1 Also includes Multiple Contingencies due to relay or breaker failures Requires more cases/scenarios Includes short-circuit analysis

3.A. APS TPL Plan for 2015 Study Near-Term Long-Term Year 1 (2016) 2 (2017) 3 4 5 (2020) 6 7 8 9 (2024) 10 Steady State Peak Load (Summer) X Peak load sensitivity Off-Peak (Spring) Off-Peak sensitivity Stability ?

3.A. 2016-2025 Ten-Year Plan Methodology Coordinated Base Cases 2015HS – SASG/AZ coordinated case used to build heavy summer 2016-2019 2020HS – AZ coordinated case used to build heavy summer 2021-2023 2024HS – SWAT/AZ coordinated case used to build heavy summer 2025 (same SWAT updated case submitted to WestConnect) The intermediate cases are APS/SRP coordinated 69kV transmission models incorporated Most up-to-date forecasts for peak summer loads N-0 and N-1 analysis conducted for all ten years Note: AZ coordinated cases also included IID

3.A. 2016-2025 Ten-Year Plan Status AZ Seed cases are complete (2016HS, 2020HS, 2024HS) Intermediate cases are in development Ten-Year plan studies will be performed in the summer/fall Draft results typically available during 4th Quarter Stakeholder meeting Ten-Year Plan filed by the end of January BTA Studies will also be completed and filed 10th Year Snapshot & Extreme Contingency RMR study needs are being evaluated

3.B. Customer Load/Resource Updates APS has all load/resource data from Network Customers and has incorporated them into the base cases Should you like to provide information for the future APS planning cycles, please see critical dates on the next slide

3.B. Feedback on the Plan? Feedback on the Plan or methodologies NERC Reliability Ten Year Plan See next slide to see how APS would evaluate plan submittals or alternatives.

3.B. Review Stakeholder proposals previously submitted APS received no stakeholder proposals in 2014 or prior to this meeting.

3.B. Submittal of additional study plan proposals If you have study ideas for APS to consider, please send a detailed message to: apstransmission@aps.com Please include (at a minimum) Your Name/Company/contact info (e-mail/phone #) What the purpose of the study request is? And how will the results be used? E.g. Determine how much load the system can accommodate without new generation/transmission? Results will be used to inform developers where there may be opportunities for additional commercial development without transmission/generation investment. What year(s) and season(s) is of interest? What type of study – reliability (power flow only?) economic?

3.B. APS Ten-Year Plan Projects 2015-2024 Transmission Plan Filed on Jan. 30, 2015

3.B. Changes since 2015 Plan was filed Two projects completed Hassayampa-North Gila #2 500kV line Energized May, 2015 New Path 49 (EOR) rating of 10,100 MW Palm Valley-Trilby Wash 230kV line Energized April, 2015 Trilby Wash now providing new source for northwestern part of valley Actively under construction Palo Verde-Delaney-Sun Valley 500kV Sun Valley-Trilby Wash 230kV Bagdad 115kV Relocation

In-Service: Hassayampa-North Gila 500kV #2 Line 2016: Delaney-Palo Verde 500kV Line Delaney-Sun Valley 500kV Line 2017: Bagdad 115kV Line Relocation Mazatzal 345/69kV Substation 2018: Morgan-Sun Valley 500kV Line Ocotillo Modernization Project

In-service: Palm Valley-Trilby Wash 230kV Line 2016: Sun Valley-Trilby Wash 230kV Line 2018: Ocotillo Modernization Project 2026: Morgan-Sun Valley 230kV Line

In-service: Hassayampa-North Gila 500kV #2 Line 2018: North Gila-Orchard 230kV Line

Bulk Transformer Additions/Replacements Description Year Two 100MVAR Reactors at Four Corners 230kV 2015/2016 Trilby Wash 230/69kV Transformer (in-service) 2015 Sun Valley 500/230kV Transformer 2016 Mazatzal 345/69kV Transformer 2017 Prescott 230/115kV Transformer #3 North Gila 500/230kV Transformer 2018 Orchard 230/69kV Transformer Orchard 230/69kV Transformer #2 Saguaro 230/69kV Transformer 2021

APS Planning - Study Requests Generation Interconnection Requests Transmission Interconnection Requests Transmission Service Requests Economic Study Requests

3.C. Generation Interconnections Active Generation Interconnection requests APS OASIS contains Generation Interconnection Queue http://www.oatioasis.com/azps/index.html 2 Solar projects - 220 MW 1 Wind projects - 1000 MW 1 Wind/Solar project – 101 MW wind/60 MW solar 3 Natural Gas projects – 2429 MW Note: Generator Queue information as of 4/23/15

A - HAA-NG 500kV line B - Gila Bend/Buckeye C – Metro Phx D - FC 1 projects 200 MW B - Gila Bend/Buckeye 2 projects 654 MW C – Metro Phx 595 MW D - FC 1200 MW E - Northern AZ 1161 MW D E C B A Note 1: Generator Queue information as of 4/23/15 Note 2: Figures displayed may not represent complete queue

3.D. Transmission Service Requests 1 Wires to Wires Interconnection Requests 42 Transmission Service Requests

3.E. Economic Study Requests Currently no Economic Study Requests

3.F. APS Planning – Comments & Questions Stakeholder comments/questions on 2014 Study Results or 2015 Study Requests Requests can be made at any time to: apstransmission@aps.com

4. Purpose of Today’s Meeting Per SRP’s OATT, SRP conducts the 2nd quarter public planning meeting to: Review its current transmission study plan provide an opportunity for transmission customers to update their loads, resources and other data review any stakeholder proposals previously submitted to SRP for study plan alternatives B) Provide updates on SRP’s transmission projects (Ten Year Plan) C) Provide updates on the generation study requests D) Provide updates on the transmission study requests E) Provide updates on the economic study requests F) Invite stakeholders to submit additional study proposals 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning 4.A. – SRP’s Study Plan SRP has two distinct, but related, transmission study plans NERC Compliance SRP’s budgetary planning The difference between the two plans: NERC Compliance: 3 seasons/scenarios, 2 discrete years (near and long term) SRP’s annual planning: 1 season, 10 consecutive years (first 6 years are for budget, remaining 4 for compliance purposes) The similarities between the two plans: Similar load forecasts, demand response They are reliability studies 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.A. 2015 NERC Compliance Study Methodology Coordinated Base Cases (Seed Cases) 2016 – AZ coordinated case used to build 2016-2019 2020 – AZ coordinated case used to build 2020-2024 2024 – AZ coordinated case used to build 2025 The intermediate cases are APS/SRP coordinated SRP NERC Compliance cases 2017 and 2021 69kV transmission models incorporated Most up-to-date forecasts for peak summer loads WECC still hasn’t released a 2025 case, so there is still no case to even begin coordination. We still need to decide what will be done here Are we using 2017 and 2021 NERC Compliance cases? We used 2016 & 2020 last year, so that’s what I’m guessing. 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.A. 2015 NERC Compliance Study Methodology NERC Compliance Studies Cases 2017 & 2021 Summer Peak & Off-peak Cases 2017 & 2021 Off-peak Cases are Low Load (spring/winter conditions) and High Import (shoulder cases with low generation in the Phoenix Metro Area) Following analyses are conducted: Thermal analysis Post-Transient Transient Stability Are we using 2017 and 2021 NERC Compliance cases? We used 2016 & 2020 last year, so that’s what I’m guessing. Are we going to use the 2017 light spring case like APS? 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.A. NERC Compliance Studies NERC STANDARD Type of Studies Completed TPL-001 (N-0) Thermal Transient Stability Post-transient 2017 Peak X Low Load High Import 2021 TPL-002 (N-1) 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.A. NERC Compliance Studies NERC STANDARD Type of Studies Completed TPL-003 (N-2) Thermal Transient Stability Post-transient 2017 Bus outages X Contingency of towers Stuck breaker & protection system failure (SLG fault) Common Corridor N-1-1 2021 TPL-004 (N-X) Substations with generation Common Corridor/Substation without generation Stuck breaker & protection system failure (3PHG fault) Mention TPL-001-4 takes effect in Jan. 2016 Note: TPL-003 Studies performed on Peak, Low Load & High Import cases 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.A. NERC Compliance Results 2014 NERC Compliance Studies were finalized by beginning of November of 2014 2015 Progress Case building under way TPL-001-4 effective 1/1/2016 SRP will perform the studies for TPL-001-4 in order to compliant after 1/1/2016 Besides nomenclature differences, major addition is requirement for short circuit studies 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.A.– Stakeholder Proposals SRP received no stakeholder proposals in 2014 or prior to this meeting

4.A. – Customer Load/Resource Updates No customers provided load/resource data in September 2014 SRP received no stakeholder proposals in 2014 or prior to this meeting. If you like to provide information for the future SRP planning cycles, please see critical dates on the next slide Is this still true? Is this slide needed for Q2? 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning 4.B. SRP Ten Year Plan 2015-2024 SRP has Filed its Ten Year Plan as of January 30, 2015 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.B. 2016-2025 Ten Year Plan Methodology Coordinated Base Cases See NERC Compliance Methodology slide #6 69kV transmission models incorporated Most up-to-date forecasts for peak summer loads TPL-001 & TPL-002 Studies Conducted for all ten years 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning NAVAJO GS 500kV System MOENKOPI (APS) 2015-2024 CEDAR MT (APS) NEVADA YAVAPAI (APS) MARKETPLACE DUGAS (APS) CHOLLA (APS) McCULLOUGH 230kV MEAD ELDORADO MORGAN (APS) SUGARLOAF PERKINS CORONADO WESTWING PINNACLE PEAK (APS) MOHAVE 345kV RUDD PALO VERDE 2016 HASSAYAMPA JOJOBA SPRINGERVILLE (TEP) KYRENE 2024 BROWNING SILVER KING PINAL WEST DUKE PINAL CENTRAL SUNZIA (SWPG) Central New Mexico 2018 EXISTING LINES FUTURE LINES FUTURE 500kV SUBSTATION EXISTING 500kV SUBSTATION All Changes since January 2014 Ten Year Plan shown in red 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning TO W.A.P.A. PINNACLE PEAK TO APS PINNACLE PEAK 230kV System W.A.P.A. SRP PINNACLE PEAK WESTWING 2015-2024 DEER VALLEY (APS) PAPAGO W.A.P.A. W.A.P.A. ALEXANDER AGUA FRIA BRANDOW GOLDFIELD THUNDERSTONE WHITE TANKS ROGERS RUDD To Silver King WARD ORME TO APS OCOTILLO LIBERTY (W.A.P.A.) BROWNING SANTAN CORBELL ANDERSON Price Road Corridor Project KYRENE RS-27 (TBD) DOUBLE CIRCUIT, PHASE TIED LINE KNOX TBD EXISTING 230kV CIRCUIT RS-28 (2017) DINOSAUR FUTURE 230kV CIRCUIT 2017 SCHRADER PFISTER TBD 2021 EXISTING 230kV SUBSTATIONS 2021 FUTURE 230kV SUBSTATIONS ABEL GENERATING STATION DESERT BASIN TO SANTA ROSA (APS) RANDOLPH TO CASA GRANDE (APS) PINAL CENTRAL All Changes since January 2014 Ten Year Plan shown in red 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning Eastern Mining Area ROOSEVELT MORMON FLAT HORSE MESA STEWART MOUNTAIN 2015-2024 TO SILVER KING 500kV FRAZIER SILVER KING 230 ELLISON PINTO VALLEY GOLDFIELD MIAMI MOONSHINE 230kV 115kV PINAL TO THUNDERSTONE CARREL CARLOTA SPURLOCK 230kV (2019) SUPERIOR TRASK OAK FLAT KNOLL RS-29 230kV (2019) RS-30 115KV (2019) RAY 2019 MORRIS FUTURE SUBSTATION KEARNY EXISTING SUBSTATION HAYDEN BONNEYBROOK (APS) GENERATING STATION ASARCO FUTURE LINE EXISTING LINE COOLIDGE (W.A.P.A.) TO APACHE (AEPCO) TRANSFORMER All Changes since January 2014 Ten Year Plan shown in red 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.B. SRP changes since 2014 Plan Completed Projects Pinal West – Duke – Pinal Central 500kV line Pinal Central – Browning 500kV line Pinal Central – Randolph 230kV line Desert Basin – Pinal Central 230kV line Pinal Central 500kV and 230kV Substation Duke 500kV Substation Browning – Rogers 230kV line New Projects Hassayampa – Pinal West 500kV Jojoba line loop in 2016 Browning – Corbell and Santan – Rogers 230kV line in 2020 Hassayampa – Pinal West 500kV #2 in 2024 Delayed Projects Superior-Silver King 115kV re-route was 2015, now 2017 Schrader-RS28 230kV line was 2016, now 2017 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.B. SRP changes since 2014 Plan Delayed Projects RS28 230kV substation was 2016, now 2017 Eastern Mining Expansion was 2018, now 2019 Sun Zia was 2017, now 2018 Silver King-RS29 230kV was 2018, now 2019 RS29 230kV substation was 2018, now 2019 RS29-RS30 115kV was 2018, now 2019 RS30 115kV substation was 2018, now 2019 Ellsworth Technology Corridor was 2019, now TBD New Superior-New Oak Flat 230kV was 2021, now TBD New Oak Flat-Silver King 230kV was 2021, now TBD Abel 500kV Substation was 2020, now TBD Removed Projects None 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning 4.C. – 4.E. Transmission Planning Study Process SRP evaluates plan submittals or alternatives according to the following flowchart. 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.C.-E. SRP Planning - Study Requests Generation Interconnection Requests Transmission Interconnection Requests Transmission Service Requests Economic Study Requests 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.C. SRP Planning –Interconnection Requests (Transmission) Currently there are no Transmission Interconnection Requests under study 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.C. Interconnection Requests (Generation) A. EAST VALLEY 2- Solar Projects 100MW B. EMA 115kV AREA 3- Solar Projects 105MW Generation Interconnection Requests listed on this slide are for SRP solely owned transmission A B 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.D.-E. SRP - Transmission Service and Economic Study Requests SRP received one Transmission Service Request There are no Economic Study Requests 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.F. Submittal of Additional Study Plan Proposals If you have study ideas for SRP to consider, please send a detailed message to: SRP.TransmissionPlanning@srpnet.com Please include (at a minimum): Your Name/Company/contact info (e-mail/phone #) What the purpose of the study request is? And how will the results be used? What year(s) and season(s) is of interest? What type of study – reliability (power flow only?), economic? 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

4.G. SRP Planning – Comments & Questions Stakeholder comments/questions on 2015 Study Results 12/18/2014 APS/SRP Stakeholder Meeting for Transmission Planning

5. Stakeholder Questions & Comments Open discussion WestConnect – http://www.westconnect.com/documents.php APS OASIS – http://www.oatioasis.com/azps/index.html SRP OASIS – http://www.oatioasis.com/srp/index.html

6. Action Items Review any action items, assignments, and due dates