APS/SRP Stakeholder Meeting For Transmission Planning FERC Order 890 OATT Attachment K (APS Attachment E) APS Transmission Planning SRP Transmission Planning Phoenix, Arizona December 16, 2010

1.Welcome, Introductions, and Meeting Overview 2.Status of Action Items-6/24/10 Joint APS/SRP 4 th Quarter Public Planning Meeting 3.SRP Planning a.SRP Planning Calendar & Methodology b.Proposed SRP Ten-Year Plan c.SRP Transmission Projects for Renewable Generation d.Interconnection Requests and Transmission Service Requests e.Requests Received for Economic Planning Studies f.Stakeholders invited to submit requests for additional transmission studies g.Comments/Questions 4.APS Planning a.APS Planning Calendar & Methodology b.APS Ten-Year Plan and Renewable Transmission Projects Draft c.2010 Study Assumptions d.Interconnection Requests and Transmission Service Requests e.Requests received for Economic Planning Studies f.Stakeholders invited to submit requests for additional transmission studies g.Comments/Questions 5.Current Activities Update 6.Stakeholder Questions/Comments 7.Action Items 2 Agenda 2 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

3 Welcome Introductions Meeting Overview December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

4 2. Status of Action Items APS/SRP will try to find a way to provide Joint Participant information in some other way than being part of queues.  Ownership information, unless otherwise made public such as though a public filing, belongs to each individual owners: SRP has no right or duty to post such data on the SRP OASIS. Request APS and SRP to explore the possibility of coordinating Stakeholder meetings with Resource meetings.  Ongoing December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

5 3.a. SRP Planning Calendar & Methodology WECC/TEPPC/WestConnect Planning Calendar SRP Planning Calendar Planning Process/Methodology 5 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

66 6 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

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9 3.a SRP Planning - Calendar & Methodology Assumptions and Methodology Types of Studies Performed Proposed 2011–2020 Ten Year Plan 9 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

10 3.a Study Assumptions/Methodology  Coordinated Base Cases (Seed Cases) NERC Compliance Studies  2013 – APS/SRP 2013 coordinated case  2017 – APS/SRP 2017 coordinated case BTA Studies  2020 – WECC 2020 HS coordinated case  69kV transmission models incorporated  Most up-to-date forecasts for peak summer loads 10 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

11 NERC Compliance Studies Cases  2013 & 2017 Summer Peak & Off-peak Cases  2013 & 2017 Off-peak Cases are Low Load (winter conditions) and High Import (shoulder cases with low generation in the Phoenix Metro Area).  Following analysis are conducted:  Thermal analysis  Post-Transient  Transient Stability 3.a Study Assumptions/Methodology 11 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

Planning Methodology NERC STANDARDType of Studies Completed TPL-001 (N-0)ThermalTransient StabilityPost-transient 2013PeakX 2013Low LoadX 2013High ImportX 2017PeakX 2017Low LoadX 2017High ImportX 2017All-inX TPL-002 (N-1)ThermalTransient StabilityPost-transient 2013PeakXXX 2013Low LoadXXX 2013High ImportXXX 2017PeakXXX 2017Low LoadXXX 2017High ImportXXX 12 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

Planning Methodology NERC STANDARDType of Studies Completed TPL-003 (N-2)ThermalTransient StabilityPost-transient 2013Bus outagesXXX 2013Contingency of towersXXX 2013Stuck breakerXXX 2013Common CorridorXXX 2013N-1-1XXX 2017Bus outagesXXX 2017Contingency of towersXXX 2017Stuck breakerXXX 2017Common CorridorXXX 2017N-1-1XXX TPL-004 (N-X)ThermalTransient StabilityPost-transient 2013Substations with generationXX 2013Common Corridor/Substation without generation XX 13 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting Note: TPL-003 studies were performed on Peak, Low Load & High Import cases

14 3.b SRP Ten Year Plan Projects Draft 14 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

FUTURE LINES EXISTING LINES FUTURE 500kV SUBSTATIONEXISTING 500kV SUBSTATION SALT RIVER PROJECT 500kV SYSTEM NEVADA WESTWING KYRENE SILVER KING CORONADO CHOLLA (APS) MEAD McCULLOUGH MARKETPLACE BROWNING HASSAYAMPA RUDD PALO VERDE PINAL WEST ABEL JOJOBA SAGUARO (TBD, place holder for CATS only, no current SRP plans) SANTA ROSA 2014 TBD MORGAN(APS) Sun Valley (APS) 2014 NAVAJO GS SUGARLOAF (APS) MOENKOPI YAVAPAI PINNACLE PEAK (APS) RS20 TBD PINAL CENTRAL 2014 NORTH GILA (APS) 2014 TBD TORTOLITA (TEP) Central New Mexico SUNZIA (SPG) 2015 DUGAS (APS) December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting DELANY 2013

:  Browning-Pinal Central 500kV (it will be energized as Randolph-Browning 230kV until 2014) 2013:  Palo Verde-Delany 500kV 2014:  Delany-Sun Valley 500kV  Hassayampa-N.Gila 500kV line  Pinal West-Pinal Central 500kV  Pinal Central 500/230kV substation 2016:  Sun Valley-Morgan 500kV 2021:  Pinal Central-Abel #2 500kV SALT RIVER PROJECT 500kV SYSTEM December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

SALT RIVER PROJECT EASTERN 230kV SYSTEM GOLDFIELD THUNDERSTONE SANTAN TBD BALL/RS17 TBD BROWNING RS21 TBD 2011 ABEL/RS22 TBD DINOSAUR RS23 TBD RS20 LOOP IN TBD PFISTER/RS TBD ROGERS DESERT BASIN PINAL CENTRAL 2014 TO SILVER KING PINNACLE PEAK To CORBELL To SCHRADER CATSHV03 TBD EXISTING 230kV SUBSTATIONS FUTURE 230kV CIRCUIT EXISTING 230kV CIRCUIT FUTURE 230kV SUBSTATIONS GENERATING STATION DOUBLE CIRCUIT, PHASE TIED LINE RANDOLPH SWITCHYARD 2011 TO SILVER KING December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting BRANDOW TBD 2014

:  Dinosaur-Abel-Randolph 230kV 2014:  Desert Basin-Pinal Central 230kV line  Pinal Central - Randolph 230kV line 2019:  Pfister(RS24) 230/69kV substation  Abel-Pfister(RS24)-Schrader 230kV  Abel-Pfister(RS24)-Santan 230kV SALT RIVER PROJECT EASTERN 230kV SYSTEM December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

BRANDOW WARD CORBELL ALEXANDER WESTWING KYRENE ANDERSON WHITE TANKS ORME SRP PINNACLE PEAK PAPAGO LIBERTY (W.A.P.A.) AGUA FRIA DEER VALLEY (APS) ROGERS TO APS OCOTILLO TO APS PINNACLE PEAK TO W.A.P.A. PINNACLE PEAK W.A.P.A. KNOX SCHRADER RUDD TBD RS26 TBD SALT RIVER PROJECT WESTERN 230kV SYSTEM TBD BALL/RS17 SANTAN THUNDERSTONE To BROWNING To PFISTER/RS24 EXISTING 230kV SUBSTATIONS FUTURE 230kV CIRCUIT EXISTING 230kV CIRCUIT FUTURE 230kV SUBSTATIONS GENERATING STATION DOUBLE CIRCUIT, PHASE TIED LINE To GOLDFIELD 19 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting RS25 TBD

GENERATING STATION EXISTING LINE FUTURE LINE 115kV MIAMI PINAL SUPERIOR SPURLOCK MOONSHINE ELLISON FRAZIER ROOSEVELT TBD RAY MORRIS KEARNY NEW HAYDEN EXISTING SUBSTATION HAYDEN STEWART MOUNTAIN MORMON FLAT HORSE MESA GOLDFIELD 230kV OAK FLAT PINTO VALLEY KNOLL TO APACHE (AEPCO) TO THUNDERSTONE COOLIDGE (W.A.P.A.) TO SILVER KING 500kV SILVER KING 230 ASARC0 TBD TBD (230kV) SEE DETAIL DETAIL SUPERIOR 230KV SUPERIOR 115KV FUTURE SUBSTATION SALT RIVER PROJECT EASTERN MINING AREA SYSTEM CARREL BONNEYBROOK (APS) 230kV TBD RS20 TBD (230kV) TRASK CARLOTTA 20 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

Electric System Additions/Upgrades EquipmentYear Abel 1 st 230/69kV transformer 2011 Kyrene 3 rd 500/230kV transformer 2012 Rudd 1 st 230/69kV transformer 2013 Pinal Central 1 st & 2 nd 500/230kV transformers 2014 Schrader 3 rd 230/69kV transformer 2015 Pfister (RS-24) 1 st 230/69kV transformer December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

SRP Changes from 2010 to kV Projects  2015 SunZia Project Delayed from 2013/2014  2021 Pinal Central – Abel #2 Delayed from kV Projects  2019 Pfister(RS24) 230kV Transmission Project Delayed from 2018/2019  TBD RS26 230kV Project Delayed from 2014 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting22

23  Pinal West – Pinal Central 500kV line  Pinal Central – Tortolita 500kV line  Palo Verde – Delany 500kV line 3.c. SRP Planning – Transmission Projects for Renewable Generation December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

24 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

25  Generation Interconnection Requests  Transmission Interconnection Requests  Transmission Service Requests  Economic Study Requests SRP Planning - Study Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

26 Generation Interconnection Requests listed at the next slide are for SRP solely owned transmission. The generation interconnecting in SRP’s queue is: 4 Natural Gas Projects2011 MW 3 Wind Projects1200 MW 10 Solar Projects 245 MW 3.d. SRP Planning – Study Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

27 4 Natural Gas projects MW 2 Wind projects MW The joint interconnection requests are listed on SRP OASIS December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting The joint interconnection requests are listed on SRP OASIS

28  Currently there are no Transmission Interconnection Requests under study 3.d. SRP Planning - Study Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

29  Currently there are no Transmission Service Requests under study 3.d. SRP Planning - Study Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

30 Currently there are no Economic Study Requests 3.e. SRP Planning - Study Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

31 SRP invites Stakeholders to submit request for additional transmission studies 3.f. Stakeholders Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

32 3.g. SRP Planning – Comments & Questions Stakeholder comments/questions on 2010 Study Results or 2011 Study Requests Requests can be made at any time to:  December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

33 4.a. APS Planning Calendar & Methodology WECC/TEPPC/WestConnect Planning Calendar APS Planning Calendar Planning Process/Methodology 33 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

34 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

35 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

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37 4.b. APS Ten Year Plan Projects Draft- Plans not finalized until mid/end of January 37 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

: Morgan 500/230kV substation (In- Service) Morgan-Pinnacle Peak 500kV & 230kV lines (In-Service) 2012: Youngs Canyon 345/69kV substation 2013: Delany-Palo Verde 500kV line 2014: Delany-Sun Valley 500kV line Hassayampa-N.Gila 500kV line D. Basin-Pinal Central 230kV line Pinal Central-Sundance 230kV line Mazatzal 345/69kV substation Bagdad 115kV relocation 2015: TS12 230/69kV substation 2016: Sun Valley-Morgan 500kV line December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

39 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

40 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting 2010: Morgan-Raceway 230kV (in-service) : Raceway-Pinnacle Peak 230kV (in- service) 2013: Scatter Wash 230/69kV substation 2014: Sun Valley-Trilby Wash 230kV 2015: Trilby Wash-Palm Valley 230kV

41 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

42 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting 2014: Palo Verde Hub-North Gila 500kV #2 line North Gila-TS8 230kV line

Project NamePrevious in-service date New in-service date Scatter Wash 230/69kV substation Mazatzal 345/69kV substation TS12 230/69kV substation Delany-Palo Verde 500kV line * It should be noted that in-service dates shown in this table are based on load projects, not potential interconnections. New generation interconnections may accelerate the in-service date. 43 Project Timing Changes- Preliminary 2010 to 2011 changes December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

44 1) Palo Verde to Delany 500kV 2) Palo Verde to North Gila 500kV 3A) Palo Verde to Valley Load (Liberty) 3B) Gila Bend to Valley Load (Liberty) 4) Delany to Blythe 500kV 4.b. APS Planning – Transmission Projects for Renewable Generation December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

45 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

46 4.c. 2010/2011 Study Assumptions Coordinated Base Cases (Seed Cases)  SATS 2012 case  WECC 2015HS  WestConnect case 69kV transmission models incorporated Most up-to-date forecasts for peak summer loads December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

47 Summer Peak cases  TPL-001 & TPL-002 Thermal analysis (All 10 years) Post-Transient (All 10 years) Transient Stability (2013 & 2019)  TPL-003 & TPL-004 (2013 & 2019) Maximum Load Serving Capability for Phx & Yuma (All 10 years)  TPL-001 & TPL-002 Thermal and Post Transient Low Load case (2014)  Thermal, Transient Stability, & Post Transient  TPL-001 thru TPL c NERC/WECC Reliability Studies 47 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

NERC/WECC Studies 48 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting APS TPL Planning Methodology: Summer NERC STANDARDSTUDIES COMPLETED TPL -001(n-0)ThermalTransient StabilityPost Transient 2013SILX 2013 PEAKX 2019SILX 2019 PEAKX TPL-002 (n-1) 2013SIL (Lines, xfmrs, gens)X X 2013 PEAK (Lines, xfmrs, gens)XXX 2013 MLSC (Lines, xfmrs, gens)X X 2019 SIL (Lines, xfmrs, gens)X X 2019 PEAK (Lines, xfmrs, gens)XXX 2019 MLSC (Lines, xfmrs, gens)X X TPL-003 (n-2) 2013Stuck Breaker/Breaker FailureXXX 2013 N-1-1XXX 2013 Bus SectionXXX 2019Stuck Breaker/Breaker FailureXXX 2019 N-1-1XXX 2019 Bus SectionXXX TPL-004 (n-xx) 2013Major Substations With/Without GenerationXXX 2013Stuck Breaker/Breaker FailureXXX 2013Common CorridorXXX 2019Major Substations With/Without GenerationXXX 2019Stuck Breaker/Breaker FailureXXX 2019Common CorridorXXX

NERC/WECC Studies 49 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting APS TPL Planning Methodology: WINTER SEASON - Low load NERC STANDARDSTUDIES COMPLETED TPL -001(n-0)ThermalTransient StabilityPost Transient 2013 WINTER - Low loadX TPL-002 (n-1) 2013 TRANSMISSION LINEXXX 2013 XFMRX X 2013 GENERATIONX X 2013 REACTORSX X TPL-003 (n-2) 2013 Stuck BreakerXXX 2013 N-1-1XXX TPL-004 (n-xx) 2013 Loss of All Generation Units at a Station XXX 2013 Common CorridorXXX

50 Generation Interconnection requests  APS OASIS contains Generation Interconnection Queue (as of 12/8/10) 69 Solar projects MW 14 Wind projects MW 2 Others (Coal, NG, Biomass, etc.) MW 4 Transmission Interconnection Requests Currently 3 Transmission Service Requests waiting to begin study Currently no Economic Study Requests 4.d. Interconnection & Study Requests December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

51 4.e&f. Stakeholder Study Requests Study requests can be taken at today’s meeting Study requests can be made at any time to:  December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

52 4.g. Comments & Question Comments?????? Questions!!!!!!!!!! 52 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

5. Current Activities Updates  NERC Compliance Reliability Standard MOD- 029 – Rated System Path Methodology 53 December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

54 6. Stakeholder Questions and Comments  Open discussion Reference Material WestConnect – APS OASIS – SRP OASIS – December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting

55 7. Action Items  Review any action items identified for follow up  Information addressing action items to be posted on APS and/or SRP OASIS and WestConnect website December 16, 2010 APS & SRP 4th Quarter Stakeholder Meeting