1. Arizona Transmission System Overview November 18, 2014 Tribal Solar Working Group 1

2. What is SWAT? Southwest Area Transmission (SWAT) is a voluntary and open study group comprised of regulators, governmental entities, transmission users, transmission owners, transmission operators, environmental entities, and other stakeholders. The goal of SWAT is to promote collaborative regional transmission planning in the Desert Southwest. http://www.westconnect.com/planning_swat.php 2

3. SWAT Subcommittee Footprints Arizona Nevada California Utah Colorado New Mexico SWAT NM AZ Saguaro Rudd SWAT Southwest Area Transmission AZArizona Transmission System NMNew Mexico Transmission EVSGEldorado Valley Study Group Footprint wide work groups: Short Circuit, Transmission Corridor, California Interface, Coal Reduction Assessment Task Force 500kV 345kV Web Sites WestConnect: http://www.westconnect.com/http://www.westconnect.com/ SWAT: http://www.westconnect.com/planning_swat.phphttp://www.westconnect.com/planning_swat.php Browning Kyrene Pinnacle Peak McKinley Springerville Silver King Greenlee Tortolita W Luna Coronado Cholla Moenkopi South Vail Hidalgo Diablo Afton Caliente Newman Arroyo Amrad Artesia Blackwater BA Taos Ojo San Juan Four Corners West Mesa Glen Canyon Mead Crystal Shiprock Navajo Devers Palo Verde Hub Perkins Liberty North Gila Norton Sandia Winchester Market Place McCullough Eldorado Mira Loma Colorado River Red Bluff Lugo EVSG Victorville Harry Allen 3

4. SWAT in Relation to other Planning Regions 4

5. Difference between “Transmission” and “Distribution” Generally, “transmission” means 100 kV or greater. It is the power system used for wholesale transactions, and interconnection is regulated by the Federal Energy Regulatory Commission. “Distribution” is generally less than 100 kV and interconnection rules are often defined by state, local utility, or Tribe. This presentation only focuses on the transmission level, but distribution level projects are still important to the entire grid. 5

6. Major Arizona Transmission 6

7. http://www.azcc.gov/divisions/utilities /electric.asp Map of AZ Electric Companies 7

8. Ownership of Transmission in Arizona Arizona Public Service Salt River Project Southwest Transmission Cooperative Tucson Electric Power Western Area Power Administration – Desert Southwest Region 8

9. APS 9

10. 10

11. APS 11

12. SRP 12

13. 13

14. 14

15. 15

16. 16

17. SWTC Northern 17

18. SWTC Southern 18

19. SWTC Western 19

20. TEP 20

21. WAPA-DSW 21

22. Some Developer Transmission Projects Centennial West Clean Line (2020) – http://www.centennialwestcleanline.com/site/home http://www.centennialwestcleanline.com/site/home Harcuvar Transmission Project (TBD) Long View Energy Exchange (2021) – http://longviewee.com/ http://longviewee.com/ Southline (2017) – http://www.southlinetransmissionproject.com/ http://www.southlinetransmissionproject.com/ SunZia (2018) – http://www.sunzia.net/ http://www.sunzia.net/ 22

23. Centennial West Clean Line 23

24. Harcuvar Transmission Project 24

25. Longview Energy Exchange 25

26. Southline 26

27. Southline (renewable resources map) 27

28. SunZia 28

29. SunZia (solar resources map) 29

30. Transmission Projects Under Development 30

31. WECC Paths http://www.wiebgridtracker.com/ The flows on some transmission lines interact with one another, and they are grouped together as “paths.” Congestion on these paths can be a considerable limitation on the ability to move power between regions of the grid. In Arizona, major paths are: Path 22 (Southwest of Four Corners), Path 23 (Four Corners), Path 50 (Cholla to Pinnacle Peak), Path 51 (Southern Navajo), Path 54 (Coronado to Silverking) – Limit flows from coal resource areas to central Arizona Path 49, East of the Colorado River - Limits exports to California Path Reports: https://www.wecc.biz/Reliability/TAS_P athReports_Combined_FINAL.pdf https://www.wecc.biz/Reliability/TAS_P athReports_Combined_FINAL.pdf WECC Path Rating Catalog (non-public) 31

32. Maps of Existing and Future Transmission Projects Arizona Utility Ten Year Plans and Biennial Transmission Assessment filings – http://edocket.azcc.gov/Docket/DocketDetailSearch?d ocketId=17769 http://edocket.azcc.gov/Docket/DocketDetailSearch?d ocketId=17769 TEPPC – https://www.wecc.biz/TransmissionExpansionPlanning /Pages/Project-Information-Portal2.aspx https://www.wecc.biz/TransmissionExpansionPlanning /Pages/Project-Information-Portal2.aspx SWAT/WestConnect – http://www.westconnect.com/documents_results.php?c ategoryid=83 http://www.westconnect.com/documents_results.php?c ategoryid=83 32

33. Land Resource Maps for Development of New Generation and Transmission US Bureau of Land Management, Arizona Office – http://www.blm.gov/az/st/en/prog/energy/arra_solar.ht ml http://www.blm.gov/az/st/en/prog/energy/arra_solar.ht ml Open Energy Information – http://en.openei.org/wiki/Gateway:Transmission http://en.openei.org/wiki/Gateway:Transmission TEPPC Environmental Data Viewer – https://www.wecc.biz/TransmissionExpansionPlanning/ Pages/Environmental-and-Cultural- Considerations.aspx https://www.wecc.biz/TransmissionExpansionPlanning/ Pages/Environmental-and-Cultural- Considerations.aspx 33

34. Questions or More Information About SWAT Patrick Harwood Western Area Power Administration harwood@wapa.gov 602-605-2883 34