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Arizona Transmission System Overview

November 18, 2014

Tribal Solar Working Group

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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

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SWAT Subcommittee Footprints

Arizona

Nevada

California

Utah Colorado

NewMexico

SWAT

NMAZ

Saguaro

Rudd

SWAT Southwest Area TransmissionAZ Arizona Transmission SystemNM New Mexico TransmissionEVSG Eldorado Valley Study Group

Footprint wide work groups: Short Circuit, Transmission Corridor, California Interface, Coal Reduction Assessment Task Force

500kV 345kV

Web SitesWestConnect: http://www.westconnect.com/

SWAT: http://www.westconnect.com/planning_swat.php

Browning

Kyrene

PinnaclePeak

McKinley

Springerville

SilverKing

Greenlee

Tortolita

W W

Luna

Coronado

ChollaMoenkopi

SouthVail

Hidalgo

Diablo

Afton

CalienteNewman

Arroyo

AmradArtesia

Blackwater

BA

TaosOjo

San Juan

FourCorners

West Mesa

GlenCanyon

Mead

Crystal

Shiprock

Navajo

Devers

PaloVerdeHub

Perkins

Liberty

North Gila

Norton

Sandia

Winchester

Market Place

McCullough

Eldorado

Mira Loma Colorado River

Red Bluff

Lugo

EVSGVictorville

Harry Allen

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SWAT in Relation to other Planning Regions

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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.

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Major Arizona Transmission

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http://www.azcc.gov/divisions/utilities/electric.asp

Map of AZ Electric Companies

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Ownership of Transmission in Arizona

• Arizona Public Service• Salt River Project• Southwest Transmission Cooperative• Tucson Electric Power• Western Area Power Administration – Desert

Southwest Region

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APS

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APS

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APS

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SRP

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15

16

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SWTCNorthern

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SWTCSouthern

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SWTCWestern

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TEP

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WAPA-DSW

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Some Developer Transmission Projects

• Centennial West Clean Line (2020)– http://www.centennialwestcleanline.com/site/home

• Harcuvar Transmission Project (TBD)• Long View Energy Exchange (2021)

– http://longviewee.com/

• Southline (2017)– http://www.southlinetransmissionproject.com/

• SunZia (2018)– http://www.sunzia.net/

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Centennial West Clean Line

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Harcuvar Transmission Project

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Longview Energy Exchange

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Southline

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Southline (renewable resources map)

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SunZia

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SunZia (solar resources map)

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Transmission Projects Under Development

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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_PathReports_Combined_FINAL.pdf

• WECC Path Rating Catalog (non-public)

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Maps of Existing and Future Transmission Projects

• Arizona Utility Ten Year Plans and Biennial Transmission Assessment filings– http://

edocket.azcc.gov/Docket/DocketDetailSearch?docketId=17769

• TEPPC– https://

www.wecc.biz/TransmissionExpansionPlanning/Pages/Project-Information-Portal2.aspx

• SWAT/WestConnect– http://

www.westconnect.com/documents_results.php?categoryid=83

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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.html

• Open Energy Information– http://en.openei.org/wiki/Gateway:Transmission

• TEPPC Environmental Data Viewer– https://

www.wecc.biz/TransmissionExpansionPlanning/Pages/Environmental-and-Cultural-Considerations.aspx

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Questions or More Information About SWAT

Patrick Harwood

Western Area Power Administration

harwood@wapa.gov

602-605-2883