March 2, 2015 Tracy Rolstad Chair, Technical Studies Subcommittee Avista Corp. 1411 E Mission Ave Spokane, WA 99252 Enoch Davies Western Electricity Coordinating Council 155 North 400 West Salt Lake City, UT 84103-1114

Subject: Idaho Power’s 2015 WECC Annual Progress Report Dear Tracy and Enoch:

Attached is Idaho Power’s 2015 WECC Annual Progress Report. Please contact me if you have any questions.

Sincerely, Mark D. Hanson System Planning Engineer Enclosure cc: D. M. Angell – PCC Representative O. A. Ciniglio – TSS Representative E. B. Bakie – SRWG Representative

Mark D. Hanson System Planning Engineer MHanson@idahopower.com (208) 388-2253

Idaho Power 2015 WECC Annual Progress Report

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Waiver of “Significant Transmission Project” Status Idaho Power is requesting waiver of the “Significant Transmission Project” status for the following projects:

Midpoint T232 230/138 kV Transformer Addition Project

Midpoint West Upgrade Project

Hemingway - Boardman Transmission Project Idaho Power’s 2013 Integrated Resource Plan, a biennially-produced 20-year resource plan for meeting our electric service obligation, identified Pacific Northwest generation resources as one component of the preferred resource portfolio. Requirements of Idaho Power’s wholesale transmission customers are also increasing. The existing transmission system connecting Idaho Power to the Pacific Northwest is fully subscribed during high-demand periods. To meet the need for more transmission capacity with the associated improvement in system reliability, Idaho Power plans to build a 500 kV transmission line from southern Idaho to northeast Oregon.

The plan of service is to construct a 300 mile 500 kV transmission line from Hemingway station in southwestern Idaho to a new station, Grassland or Longhorn depending on final routing, near the existing Boardman Power Plant in northeastern Oregon. The Hemingway-Boardman Transmission Line Project’s proposed and alternative routes are shown in Figure 1. The Hemingway-Boardman Transmission Line Project scheduled in-service date will be no earlier than 2020.

Path 14 transfer capacity ratings with the Hemingway-Boardman Transmission Project facilities are expected to increase to 2250 MW west to east (a 1050 MW increase) and a 3400 MW east to west (a 1000 MW increase). Project facilities are listed below:

Hemingway-Boardman 500 kV line, 300 miles with approximately 50% series compensation (split equally at each end); the western termination will be at the Grassland switching station near the Boardman Power Plant

Hemingway 500 kV Line Terminal with Shunt Reactors and Series Capacitor

Grassland/Longhorn 500 kV Line Terminal with Shunt Reactors and Series Capacitor and 150 Mvar, 500 kV Shunt Capacitor

Hemingway-Bowmont #2 230 kV line, 13 miles with single 1590 MCM ACSR “Lapwing” conductor

Bowmont-Hubbard 230 kV line, 16 miles with single 1590 MCM ACSR “Lapwing” conductor

Bowmont, 2nd 230/138 kV 300 MVA Auto-Transformer

The Hemingway-Boardman Transmission Project will conform to the NERC TPL-001-4 Standard and other corresponding regional System Performance requirements at the time, if any,

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and the WECC “Overview of Policies and Procedures for Project Coordination Review, Project Rating Review, and Progress Reports.”

A Hemingway-Boardman Transmission Project Comprehensive Progress Report (Phase I) was released for comment in November 2008 and was granted Phase II status in March 2009. Idaho Power began the Phase II study process in 2011; the initial kick-off project review work group meeting was held on June 22, 2011, and the second project review group meeting was held on November 15, 2011.

The third project review group meeting was held on March 22, 2012. On August 10, 2012, a conference call/webinar was held to solicit comments on the initial Phase II draft report. In August 2012, Idaho Power submitted the Idaho-Northwest Up-rate, Hemingway-Boardman 500 kV Transmission Project Phase II Report to WECC and was granted Phase III status on November 29, 2012 with an Accepted Rating of 2250 MW west-to-east and 3400 MW east-to-west.

On December 19, 2014, the BLM released the Draft Environmental Impact Statement (DEIS) for the Boardman to Hemingway Transmission Line Project (B2H). The DEIS reflects the analysis of the potential effects of the Proposed Action and alternatives, including a no-action alternative. The DEIS release date began a 90-day public comment period that will end on March 19, 2015.

Idaho Power 2015 WECC Annual Progress Report

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Figure 1 Hemingway to Boardman 500 kV Transmission Line Project

Proposed & Alternative Routes

Idaho Power 2015 WECC Annual Progress Report

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Gateway West Transmission Project Please see the Gateway West Transmission Project section in PacifiCorp’s 2015 WECC Annual Progress Report for current Gateway West Transmission Project details. Based on the agreement between PacifiCorp and Idaho Power, executed in early 2012, PacifiCorp (Rocky Mountain Power) will assume responsibility for shepherding all Gateway West transmission facilities through the National Environmental Policy Act (NEPA) process and through the project construction phase.

The Gateway West Transmission Project facilities in the Idaho area are listed below:

Kinport-Midpoint 345 kV line (existing), will be split/converted to: Kinport-Borah 345 kV line Borah-Midpoint 500 kV line (constructed 500 kV/operating at 345 kV)

Borah, 500/345 kV 1500 MVA Auto-Transformer

Populus-Borah 500 kV line, 55 miles

Cedar Hill-Hemingway 500 kV line, 161 miles with approximately 50% series compensation

Cedar Hill-Midpoint 500 kV line, 34 miles (Phase 2)

Midpoint-Hemingway #2 500 kV line, 126 miles with approximately 50% series compensation (Phase 2)

Midpoint T232 230/138 kV Transformer Addition Project A second 230/138 kV 200 MVA transformer will be installed at the Midpoint substation due to anticipated load growth in the Magic Valley area. The scheduled/projected in-service date is late 2019 to early 2020. This project is intended for load service and has no significant impact on the WECC transmission system.

Midpoint West Upgrade Project The 230 kV looped connection in and out of the Rattlesnake switching station, currently installed in the Midpoint-Boise Bench 230 kV #2 line, will be relocated to the Midpoint-Boise Bench 230 kV #1 line between DRAM and Justice. Both 230 kV lines, as well as the Midpoint-Boise Bench 230 kV #3 line, are all part of Idaho's internal Midpoint West path. In addition to the relocation, the series capacitor banks at Midpoint on the #2 and #3 lines will be replaced and increased to 70% comp each. These upgrades are being done to gain approximately 275 MW of east to west transfer capability across Midpoint West with the added benefit of approximately balancing the flows on the Midpoint-Boise Bench 230 kV #2 & #3 lines. We expect the in and out relocation for Rattlesnake to be completed by the end of May, 2015. We expect the series capacitor bank replacements to be completed by the end of September, 2015. This project has no significant impact on the WECC transmission system

Please direct all questions or concerns regarding these projects to:

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Mark D. Hanson System Planning Engineer Idaho Power Company 1221 W Idaho P.O. Box 70 Boise, Idaho 83707-0070

Tel. (208) 388-2253 Fax. (208) 388-6647 E-mail MHanson@idahopower.com