TransWest Express Project

Transcription

1 A subsidiary of Pinnacle West Capital Corporation Phase 1--Feasibility Study Study Plan Version 2

2 Contents Page Introduction Objective. 2 Scope Transmission Alternatives Alternative A Alternative B Alternative C Alternative D Base Case Description Transmission Schedules Methodology Final Report Study Schedule January 30, 2006 i

3 Introduction On October 21, 2005 Arizona Public Service Company (APS) announced publicly its intention of exploring the feasibility of constructing two new 500 kv transmission lines from Wyoming (Powder River Basin and nearby high-quality open range wind locations) to northern Arizona to provide Arizona and other states (NM, NV, CA and UT) access to over 6000 MW of coal and wind resources in Wyoming. The new transmission project from Wyoming to Arizona, the (See Figure 1), is planned to be operational in 2013 and is expected to deliver 3000 MW of power to meet rapid load growth in Arizona and the southwest. Wyoming All Lines are 500 kv TransWest Express Project Existing Lines Upgrades Other Planned Projects Power Plant Substation California Nevada Los Angeles Las Vegas N.Gila Salt Lake City Utah Navajo Arizona Phoenix/ Tucson Four Corners New Mexico Figure 1: The has a three-phase implementation plan. These are: Phase 1- Feasibility study Phase 2- Technical study and permitting Phase 3- Implementation APS has elected to sponsor the feasibility study for the project. The feasibility study will include high level technical and economic analyses. This study plan outlines the objective, scope and methodology for the technical part of the feasibility study. The study will be performed as a separate, project-specific study January 30,

4 that adopts as a starting point the transmission, resource, and other assumptions and plans developed in WECC, STEP, RMATS and other regional planning processes. Study results and data will be provided to other regional planning processes. High level power flow, transient and post-transient analyses will be performed on four different transmission alternatives capable of exporting 3000 MW of power from Wyoming to Arizona and the southwest. A feasibility study report that recommends the most desirable transmission plan, from a technical perspective, will be issued. Objective This study will evaluate the electrical performance of each of the 500 kv transmission alternatives capable of exporting up to 3000 MW of power from Wyoming to Arizona, New Mexico, Utah, Nevada and California. The transmission alternatives will be ranked and the most technically desirable plans will be recommended for further detailed technical and economic evaluation under the Phase 2 of the TransWest Express implementation plan. Scope The scope of the feasibility study will include: Performing high level power flow, transient and post-transient studies on all the transmission alternatives under evaluation. Determining need, size and location of series compensation on all the transmission alternatives. Determining need, amount and location of reactive power support to meet reactive margin requirements. Identifying transmission constraints and the associated critical contingencies for each transmission alternative. Quantifying transmission losses for each transmission alternative. Highlighting incremental flows on the major transmission lines and interfaces. High level capital and O&M cost estimates for the preferred transmission plans. Demonstrating that the recommended transmission alternative meets the WECC/NERC and any affected company s applicable planning standards. Demonstrating that the recommended transmission alternative is capable of exporting 3000 MW of power from Wyoming to Arizona and other southwest states subject to the different transmission schedule scenarios defined under the Transmission Schedules section. January 30,

5 Transmission Alternatives 1. Alternative A Two new 500 kv lines from Dave Johnston to Mona (on separate right of ways). One of the 500 kv lines will have connections at Jim Bridger and planned Oquirrh Substation in Utah. New 500 kv lines from Mona to Navajo and Crystal. New 500 kv substations at Dave Johnston, Jim Bridger, Oquirrh and Mona. New 500/345 kv transformers at Jim Bridger (possibly with a 500/345 kv phase shifting transformer), Oquirrh and Mona. Additional 500/230 kv transformer will be modeled at Dave Johnston. Alterntive A Utah Wyoming Jim Bridge r Dave Johnston Nevada Salt Lake City Oquirrh Mona All Lines are 500 kv TransWest Express Project Existing Lines Upgrades Other Planned Projects Power Plant Substation California Los Angeles Las Vegas N.Gila Navajo Arizona Moenkopi Phoenix/ Tucson Four Corners New Mexico Figure 2:, Transmission Alternative A January 30,

6 2. Alternative B Two new 500 kv lines from Dave Johnston to Mona (on separate right of ways). One of the 500 kv lines will have connections at Jim Bridger and planned Oquirrh Substation in Utah. New 500 kv lines from Mona to Crystal and Four Corners. With additional 500 kv line from Four Corners to Pinnacle Peak. New 500 kv substations at Dave Johnston, Jim Bridger, Oquirrh and Mona. New 500/345 kv transformers at Jim Bridger (possibly with a 500/345 kv phase shifting transformer), Oquirrh and Mona. Additional 500/230 kv transformer will be modeled at Dave Johnston. Alterntive B Utah Wyoming Jim Bridge r Dave Johnston Nevada Salt Lake City Oquirrh Mona All Lines are 500 kv TransWest Express Project Existing Lines Upgrades Other Planned Projects Power Plant Substation California Los Angeles Las Vegas N.Gila Navajo Arizona Moenkopi Phoenix/ Tucson Four Corners New Mexico Figure 3:, Transmission Alternative B January 30,

7 3. Alternative C Two new 500 kv lines from Dave Johnston to Mona (on separate right of ways). One of the 500 kv lines will have connections at Jim Bridger and planned Oquirrh Substation in Utah. New 500 kv lines from Mona to Navajo and Four Corners. With additional 500 kv line from Four Corners to Pinnacle Peak. New 500 kv substations at Dave Johnston, Jim Bridger, Oquirrh and Mona. New 500/345 kv transformers at Jim Bridger (possibly with a 500/345 phase shifting transformer), Oquirrh and Mona. Additional 500/230 kv transformer will be modeled at Dave Johnston. Alterntive C Utah Wyoming Jim Bridge r Dave Johnston Nevada Salt Lake City Oquirrh Mona All Lines are 500 kv TransWest Express Project Existing Lines Upgrades Other Planned Projects Power Plant Substation California Los Angeles Las Vegas N.Gila Navajo Arizona Moenkopi Phoenix/ Tucson Four Corners New Mexico Figure 4:, Transmission Alternative C January 30,

8 4. Alternative D New 500 kv DC line from Dave Johnston to Pinnacle Peak New 500 kv substation at Dave Johnston New 500 kv converter stations at Dave Johnston and Pinnacle Peak New 500/230 kv transformer at Dave Johnston Alterntive D Wyoming Dave Johnston Nevada Utah All Lines are 500 kv TransWest Express Project Existing Lines Upgrades Other Planned Projects Power Plant Substation California Los Angeles Las Vegas N.Gila Navajo Arizona Moenkopi Phoenix/ Tucson Four Corners New Mexico Figure 4:, Transmission Alternative D January 30,

9 Base Case Description The approved WECC 2014 heavy summer peak load (14hs1a) case will be used as the starting power flow base case for the feasibility study. This base case will be modified to reflect forecasted in-10 heat wave load for Arizona and the southwestern states. New transmission and generation projects that are approved and planned to be online by 2013 in Arizona, Wyoming, Utah and the southwest will be modeled. Pre-project case will also model all transmission projects which are in Phase 2 of the WECC path rating process. The following projects will be included in the preproject case: STEP short term upgrade project (2006) Harquahala-Devers 500 kv line (2009) Palo Verde TS5 500 kv line (2009) EOR project (2008) Moenkopi-Eldorado Upgrade (2009)? Path 51 upgrade (2009) Hassyampa- Pinal West 500 kv line (2008) VV1 500 kv switching station (2009) Navajo Transmission Project (2010) Pinal West- Browning 500 kv line (2013) TS5-Raceway 500 kv line (2012) Raceway -Pinnacle Peak 500 kv (2010) Hassyampa- N. Gila #2 500 kv line (2012) Potential future Utah resources to be provided by PacifiCorp The post-project cases will model a total of 3000 MW of new resources at Dave Johnston 500 kv Substation. These resources will be scheduled to stress the two new 500 kv lines south of Dave Johnston based on the transmission schedule scenarios provided under Table 1 for each transmission alternative. Transmission Schedules The following transmission schedules will be adhered to in the evaluation of the transmission alternatives. Transmission Transmission Schedules (MW) Alternative Arizona Utah S. Nevada Colorado S. California Alternative A Alternative B Alternative C Alternative D Table 1:, Transmission Schedules January 30,

10 Methodology The pre-project base case will be tested to ensure compliance with WECC/NERC and other affected company planning standards. The 3000 MW new resource will be modeled as coal-fired plants for this feasibility study. The output of the coal plants will be injected at Dave Johnston 500 kv Substation. For each transmission alternative, transfers will be made according to transmission schedule scenarios provided under Table 1 until the flow on the two new 500 kv lines south of Dave Johnston is 3000 MW or a critical transmission facility limit is reached. The limiting facility and the associated transfer level will be identified for each transmission alternative. The initial phase of the study will focus on power flow analysis. Subsequent phases of the study will examine post-transient voltage and stability performance. As part of the power flow study the following critical contingencies will be simulated. South of Dave Johnston 500 kv lines Navajo-Crystal 500 kv line South of Navajo 500 kv lines Moenkopi-El Dorado 500 kv line Moenkopi Four Corners 500 kv line Moenkopi Westwing 500 kv line Perkins-Mead 500 kv line Four Corners- Cholla 345 kv line Palo Verde-Westwing 500 kv line Palo Verde Devers 500 kv Harquahala-Devers 500 kv line Hassyampa-N. Gila 500 kv line Palo Verde 2 units outage Navajo 2 units outage Additional list to be supplied by PacifiCorp The study will also focused on outages of the proposed transmission alternatives. The power flow study will be performed and the results analyzed based on the assumption that no single element is loaded above its normal continuous thermal rating under pre-contingency conditions or above its emergency ratings under contingency conditions. The post-transient analysis will be conducted and evaluated based on the assumption that the maximum voltage deviations allowed under contingency conditions in the post-transient time frame are 5% for N-1 and 10% for N-2 unless a lower standard has been previously adopted on selected buses. January 30,

11 Transient stability runs will be simulated for 20 seconds to ensure the transmission system is stable and adequately damped. The results will be assessed using WECC/NERC transient voltage dip and transient frequency criteria. All outages will be simulated using governor power flow tools. Remedial actions for each outage will be modeled according to the latest Operating Studies Subcommittee Handbook. Final Report After the power flow studies are completed, an interim report will be prepared. As a result of these studies, the scope of the projects may be refined if necessary. Once satisfactory power flow analysis has been completed, the additional posttransient voltage and stability analysis will be performed. A final feasibility report that recommends the most desirable and reliable transmission plan, from both technical and economic stand points will be issued. Study schedule Item Target Completion date Draft study plan circulated January 30, 2006 Comments received on study plan February 13, 2006 Study base cases circulated February 27, 2006 Comments received on base cases March13, 2006 Initial power flow analysis completed April 24, 2006 Interim report circulated May 1, 2006 Feasibility studies completed May 15, 2006 Final report completed May 29, 2006 January 30,