Rocky Mountain Power Sub Transmission Five Year Study

Rocky Mountain Power Sub Transmission Five Year Study Findings and Kick Off Attachment K Meeting September 10, 2015

Rocky Mountain Power Area Transmission Planning Manager: Mark Adams Area Transmission Engineers: • • Bhavana Katyal Talmage Daley Jeremy Viula Nathan Wilson Studies Engineers • Scott Murdock • Nicole De. Giulio © 2000 PACIFICORP | PAGE 2 Planning Engineers

Why Prepare the Studies? © 2000 PACIFICORP | PAGE 3 – FERC/WECC required –

Who is invited? Any individual is welcome City and Municipal officials Generation producers Large

Third Party Contributions – Load and Forecast Projects – New Points of Delivery – Anticipated Future System Upgrades 4 Including block load increases © 2000 PACIFICORP | PAGE 5 – System Power Flow Model

Basic Understanding of the Study – Field Study Document equipment 4 Verify system ratings and settings 4 – Identify System Problems & Future Recommendations – Generate a Report Brief Understanding of the Area 4 List Equipment ratings 4 Fault duties, operation schemes 4 Lists system “Problems and Future Recommendations” © 2000 PACIFICORP | PAGE 6 4

Study Restrictions – CIPS 4 The reliability of the energy grid depends not only on physical assets, but cyber assets. The North American Electric Reliability Corporation (NERC) realized that, along with protecting the physical assets, Critical Cyber Assets also need to be protected to keep the energy grid secure. © 2000 PACIFICORP | PAGE 7 – Confidentiality

Study Areas for 2015 Findings Reports © 2000 PACIFICORP | PAGE 8 Goshen –

Bhavana Katyal / Scott Murdock/ GOSHEN AREA STUDY © 2000 PACIFICORP | PAGE 9

The Goshen service area encompasses approximately 5600 square miles spanning portions of nine counties in East Idaho. The Rocky Mountain Power (RMP) portion of this area is serviced by 56 transmission and distribution substations © 2000 PACIFICORP | PAGE 10 Goshen STUDY

© 2000 PACIFICORP | PAGE 11 Goshen Study Map

Goshen STUDY Municipalities/REAs: – Idaho Falls City – Fall River, Lost River, Salmon River and Lower Valley Energy © 2000 PACIFICORP | PAGE 12 – Rocky Mountain Power (RMP) – Bonneville Power Administration (BPA) – Pacifi. Corp Energy Supply Management (ESM) – Pacifi. Corp Transmission (PT) – Idaho Power Company (IPC) – Utah Associated Municipal Systems (UAMPS)

Goshen Study – Transmission voltages studied include 230, 161, 138, 69 and 46 k. V. – There are 11 transmission line that go in/out of the area at voltage levels of 345, 230, 161 and 115 k. V © 2000 PACIFICORP | PAGE 13 – There are 10 transmission subs: Amps, Antelope, Big Grassy, Bonneville, Goshen, Rigby, Jefferson, St. Anthony, Scoville, and Sugarmill

© 2000 PACIFICORP | PAGE 14 Goshen STUDY

Goshen STUDY Transmission Lines in/out of the Goshen Area Goshen - Kinport Goshen - Three Mile Knoll 345 Antelope - Anaconda (Mill Creek) Antelope - Brady Antelope - Lost River Goshen - Blackfoot Goshen - Drummond Goshen - Fishcreek - Grace Goshen - Jefferson - Big Grassy Anaconda (Mill Creek) Goshen - Swan Valley Goshen - Palisades 230 Loop Radial 161 115 Loop Ownership Line Conductor Length Size (Miles) 2 -795 ACSR RMP 2 -1272 ACSR IPC RMP/North. Western 1 -1272 ACSR Energy 1 -1272 ACSR IPC 1 -795 ACSR RMP/BPA 1 -397. 5 ACSR IPC 1 -795 ACSR BPA 1 -250 HHCU RMP IPC/North. Western 1 -250 HHCU Energy 1 -556. 5 ACSR BPA 41 52. 82 200 58 31. 42 19 ~60 57. 22 217. 76 47 51. 71 © 2000 PACIFICORP | PAGE 15 Line Name Line Voltage Configuration (k. V)

Load Growth – Base System Loads 4 Summer 2014: 652 MW 4 Winter 2014 -2015: 383 MW – Growth 1. 6% 4 Winter: 2. 2% – Projected System Loads 4 Summer 2019: 716 MW 4 Winter 2019 -20: 443 MW © 2000 PACIFICORP | PAGE 16 4 Summer:

Goshen STUDY – System Improvements items to maintain company standards 46 items of a

System Improvements Increase Capacity Remove regulators and Replace with a new 30 MVA 69 -25 k. V LTC transformer © 2000 PACIFICORP | PAGE 18 2015 Sandune 69 -24. 9 k. V Substation Increase Capacity from 22. 4 to 30 MVA

System Improvements – Improve Voltage Control at Arco © 2000 PACIFICORP | PAGE 19

System Improvements 2016 2017 © 2000 PACIFICORP | PAGE 20 – Correct Clearance Issues

System Improvements 2017 © 2000 PACIFICORP | PAGE 21 Upgrade Belson regulators replace 416

System Improvements 2018 © 2000 PACIFICORP | PAGE 22 Increase capacity on Sand Creek

© 2000 PACIFICORP | PAGE 23 System Improvements 2018

System Improvements 2019 © 2000 PACIFICORP | PAGE 24 Mud Lake 69 -12. 47

System Improvements 2019 © 2000 PACIFICORP | PAGE 25 Upgrade Rexburg #2 regulators to

System Improvements 2019 © 2000 PACIFICORP | PAGE 26 – Upgrade Ammon regulator to

Construction Schedule Summary Construction Schedule ~ Projects Required to Maintain Company Standards 2015 Construction - In service by end of this year 7 -1 Sandune 7 -2 Arco Change out transformer. The existing unit has heating issues. this will also increase capacity Remove damaged regulators: Install 3 -167 k. VA regulators $1, 432, 000 $350, 000 2016 Construction - In service before May 1 of this year 7 -3 Jefferson-Big Grassy 161 k. V line Correct clearance issues $918, 000 2017 Construction - In service before May 1 of this year 7 -4 7 -5 Goshen-Jefferson 161 k. V line Belson Rebuild 29. 5 line miles with 795 ACSR conductor $15, 968, 000 Replace overloaded regulators with 509 k. VA units $350, 000 7 -6 7 -7 Sand Creek 69 k. V line Increase capacity: Rebuild 3. 2 miles with 795 ACSR Sugar City Voltage Improvement: Install 2 stage 24 Mvar capacitor $3, 680, 000 $3, 531, 000 2019 Construction - In service before May 1 of this year 7 -8 7 -9 7 -10 Mud Lake Sub Rexburg Bank #2 Ammon Replace overloaded regulators with 509 k. VA units Grand Total $350, 000 $27, 279, 000 © 2000 PACIFICORP | PAGE 27 2018 Construction - In service before May 1 of this year