20180329PAC to Staff WY NTTG Reg Transmission Plan Final.pdf

I\loRTHERI\I TIER
TRANSIVIISSION GROLJP
NTTG 2016-2017
REGIONAL TRANSMISSION PLAN
December 28,2017
NTTG 2016-2017 RegionalTransmission Plan 1NTTGSteeringCommitteeApproval:December 14,2017
I ndex of F ig ures a ndT a b Ies ..............................................................................................................3
Executive Summary .........................................................................................................................4
Plan Assumptions and Caveats .................................................................................................................5
The Northern Tier Transmission Group ............................................................................................6
NorthernT ie rMembers ............................................................................................................................7
Purpose of theP Ia n .........................................................................................................................8
Plan Development Process...............................................................................................................8
Biennial Cycle...........................................................................................................................................8
Bie nn i a I St udyPI a n...................................................................................................................................9
Study Methodology................................................................................................................................10
Production-Cost Modeling ............................................................................11
Power-Flow Cases .................................................................................11
Data Submission ....................................................................................................................................11
Forecasted Loads ....................................................................................13
Public Policy Consideration Scenario Requests........................................................................................15
Regional Economic Study Requests.........................................................................................................16
Initial RegionalTransmission Plan Development .....................................................................................16
I nterreg ion a I Project Coordi n ati on ..........................................................................................................18
Stress -condit i onedC asestudyResults ....................................................................................................20
Stressed Hours for Study with Production-Cost Modeling ...............................................................20
DeveIopment of Cha nge Cases ................................................................................................................22
ChangeCase Resu Its...............................................................................................................................23
High Southern Idaho Import Case...................................................................................26
High Southern Idaho Export Case ..................................................................................26
High Wyoming Wind case..........................................................................................26
Interregional Transmission Projects ................................................................................27
Re I ia b i I ity Co nc Ius i ons ............................................................................................................................27
Economic Eva lu ations.............................................................................................................................28
Capital-related Cost Metric.........................................................................................28
Energy-loss Metric ....................................................................................28
Reserve Metric..........................................................................................28
Economic Metric Analysis Conclusion...................................................................29
Final Regional Transmission Plan ............................................................................................................29
Cost Allocation.......................................................................................................................................31
Next Steps..............................................................................................................................................31
NTTG 2016-2017 Regional Transmission Plan Supporting Materials .........................................................31
G I o ssa ry .................................................................................................................................................31
NTTG 2016-2017 RegionalTransmission Plan 2
NTTG Steering Committee Approval:December 14,2017
Index of Figures and Tables
Figure 1.NTTG Final 2016-2017 RegionalTransmission Plan.....................................................................5
Figure 2.Eight-quarter Biennial Planning Cycle..............................................................................9
Figure 3.2026 NTTG Forecasted Loads........................................................................................13
Figure 4.Comparison of ForecastedResources.........................................................................14
Figure 5.Transmission Service Obligations.........................................................................15
Figure 6.Prior RTP from 2014-2015..................................................................................17
Figure 7.2016-2017 Initial RTP............................................................................................17
Figure 8.Three Interregional Transmission Projects ...............................................................................19
Figure 9.Change Case Matrix .................................................................................................24
Figure 10.Heat map of D2-Null Case....................................................................................25
Figure 11.Heat map of High Southern Idaho export case with Initial RTP facilities included...............................26
Figure 12.Change case 23 ........................................................................................29
Figure 13.Transmission Line Segments from Initial RTP not included in Final RTP..............................................30
Figure 14.NTTG Final RTP ........................................................................................30
Table 1.January 2016 data submittal-transmission additions by 2026...........................................................12
Table 2.Three Interregional Transmission Projects submitted for consideration ................................................18
Table 3.Hours selected from 2026 WECC TEPPC case to represent different NTTG system stresses..................20
NTTG 2016-2017 RegionalTransmission Plan 3NTTGSteeringCommitteeApproval:December 14,2017
Executive Summary
Would it be more efficient or cost-effective to meet future transmission needs in the Northern
Tier Transmission Group (NTTG)footprint through a regional planning framework rather than
the aggregate of local planning processesi?The NTTG 2016-2017 RegionalTransmission Plan
(RTP)poses this question and seeks to answer it.Developed in accord with NTTG Transmission
Providers'Attachment K,which includes FERC Order 1000 regional and interregional
transmission planning requirements,the plan analyzes whether NTTG's transmission needs in
2026 could best be satisfied with projects of a regional or interregional scope.
To arrive at a conclusion,NTTG used a two-year process of identifyingtransmission
requirements and performing reliabilityand economic analyses on several collections of
transmission projects,or plans:the prior (2014-2015)RTP,an Initial RTP2 made up of projects
from the prior RTP and projects included in the Full Funders'Local Transmission Plans,and a
number of change case plans.A null Change case (null case),which tests the NTTG footprint's
current transmission system stressed by the addition of loads and resources projected for
2026,showed that the NTTG system performed acceptably in only one of seven stressed
conditions studied.All the other conditions suffered performance issues that required
correction.
A technical study found that the 2014-2015 prior RTP,which included two Non-Committed
Projects (Boardman to Hemingway and portions of Energy Gateway),was not fully reliable with
the 2026 load and resource projections.The study then evaluated 23 Change cases that
explored ways to reliably meet the transmission system needs through various combinations of
the Non-Committed Projects in the Initial RTP or three proposed Interregional Transmission
Projects,or both.These Change cases were created to explore the relationship of a build-out of
wind generation in Wyoming to meet NTTG load with its impact on the transmission system
west of Wyoming and a potential expansion of the transmission system (i.e.,the Gateway West
and Gateway South projects).
The study also examined three Interregional Transmission Projects as Alternative Projects to
determine whether these projects would yield a more efficient or cost-effective regional
transmission plan for NTTG and as a part of interregional coordination and planning.The
analysis found,however,that none of the Interregional Transmission Projects could replace or
enhance the Non-Committed Projects more efficiently or cost effectively to satisfy NTTG's
regional transmission needs.
1 NTTG's regional transmission planning process is not intended to be a replacement for local
transmission or resource planning.
2 Terms are capitalized to be consistent with Attachment K.All capitalized terms are defined in the
glossary.
NTTG 2016-2017 RegionalTransmission Plan 4
NTTG Steering Committee Approval:December 14,2017
Reliability analyses narrowed the potentiallyacceptable solutions to the initial RTP and two
change cases.Subsequent economic analyses identified one of the Change cases as the more-
efficient or cost-effective case.Known in the study as Change case 23,this case includes
Boardman to Hemingway,Gateway South,portions of Gateway West,and the Antelope
projects.See the figure below for a map of those projects.
Montana
Idaho
Wyoming
Oregon
Utah
Nevada
-Boardman-Hemingway
-Gateway West (from 300kV to 500kV)
-Antelope
Gateway West
-Gateway South
Stakeholder input on the RTP was accepted and
evaluated throughoutthe biennial planning cycle.NTTG posted the Draft RTP in December
2016 (Quarter 4)for stakeholder comment and the Draft Final RTP in Quarter 6 for public
comment.The revised Draft Final RTP was made available for public comment in Quarter 7.The
Planning Committee recommended submittal of the RTP to the NTTG Steering Committee in
Quarter 8.The Steering Committee approved the RTP in Quarter 8.
Plan Assumptionsand Caveats
The NTTG 2016-2017 Regional Transmission Plan (RTP)is meant to inform local transmission
planning processes and is not a construction plan.NTTG relies on the load and resource data
submittals of its members and does not consider the re-dispatch or re-optimization of resource
assumptions.The RTP studies are completed pursuant to the NTTG Transmission Providers'
Attachment K.
NTTG's transmission plan assumes that its members'submissions are reasonable and cost-
effective.The transmission plan is not an attempt to design an optimal portfolioof resources to
meet the expected demand of the region's consumers.Instead,it is an attempt to design a
reliable and cost-effective portfolio of transmission around the inputs of NTTG Members.The
RTP is the result of the assumptions outlined in the report and solely represents a lower-cost
NTTG 2016-2017 RegionalTransmission Plan 5NTTGSteeringCommitteeApproval:December 14,2017
transmission plan than one represented by a rollup of the combined Transmission Provider's
plans.
To the degree that those NTTG Transmission Providers'inputs are not realistic or cost-effective,
the resulting NTTG Transmission Plan will likely be affected.However,NTTG regards correcting
such potential errors as work to be undertaken in the context of integrated resource plans
conducted by individual load-serving entities in their respective states.
The Northern Tier Transmission Group
The Northern Tier Transmission Group (NTTG)was formed in 2007 to provide a forum where all
interested stakeholders,including Transmission Providers,customers and state regulators,can
participate in an open,transparent,coordinated regional transmission planning process.The
process is intended to promote effective planning and use of the multi-state electric
transmission system within the NTTG footprint.
NTTG fulfills requirements of the Federal Energy Regulatory Commission (FERC)Order 1000 for
each public utility transmission provider to participate in a regional transmission planning
process that produces a regional transmission plan and,if appropriate,includes a regional cost-
allocation method.
NTTG evaluates transmission projects that move power across the regional bulk electric
transmission system,serving load in its footprint and delivering electricity to external markets.
The transmission providers belonging to Northern Tier serve more than 4 million retail
customers with more than 29,000 miles of high-voltage transmission lines.These members
provide service across much of Utah,Wyoming,Montana,Idaho and Oregon,and parts of
Washington and California.
NTTG works with other entities-the Western Electricity Coordinating Council (WECC)for
reliabilitydata and neighboring Planning Regions (e.g.,ColumbiaGrid,Westconnect and
California Independent System Operator (CAISO))for interregional project coordination.
NTTG 2016-2017 RegionalTransmission Plan 6NTTGSteeringCommitteeApproval:December 14,2017
Idaho om!
Nevada Calando
Arizona
NTTG MEMBERS
TRANSMISSION FACILITIES
NTTG
OtherWestemU.S.and
Canada Transmisslon
The NTTG footprint covers portions of seven Western states.
Northern Tier Members
Deseret Power Electric Cooperative
Idaho Power Company
Idaho Public Utilities commission
MATL LLP
Montana Consumer Counsel
Montana Public Service commission
NorthWestern Energy
Oregon Public Utility Commission
PacifiCorp
Portland General Electric
Utah Associated Municipal Power Systems (UAMPS)
Utah Office of Consumer Services
Utah Public Service Commission
NTTG 2016-2017 RegionalTransmission Plan
NTTG Steering Committee Approval:December 14,2017
Wyoming Office of Consumer Advocates
Wyoming Public Service Commission
Purpose of the Plan
The NTTG RegionalTransmission Plan (RTP)aims to produce,if possible,a more efficient or
cost-effective regional plan to transmit energy compared with a plan that rolls up the local
Transmission Providers'transmission plans and other Change case transmission plans studied.
This study process complies with FERC Order No.1000,Attachment K-Regional Planning
Process.This planning cycle marks the first time that NTTG implemented FERC Order 1000
interregional project coordination with the other western regional transmission planning
organizations.
Plan Development Process
The Regional Transmission Plan is developed through a two-year process:
1)Identification of the transmission requirement for the NTTG footprint,derived from the data
submissions
2)Reliability analysis and evaluation of the Initial RTP and Alternative Projects (including
interregional projects)through Change Cases
3)Economic analysis and evaluation comparing the annualized incremental costs of the Initial
RTP and the change cases that perform acceptably (two cases this study cycle)
4)Selection of the project or projects that yield a regional transmission plan that is more
efficient or cost-effective than the other regional transmission plans studied
5)Any projects that were submitted for the purposes of cost allocation and selected into the
RTP will go through the cost allocation process if they are deemed to be eligible for cost
allocation.
Biennial Cycle
NTTG follows a two-year,eight-quarter planning cycle to produce the 10-year Regional
Transmission Plan.In the first step,the Planningand cost Allocation Committees pre-qualify3
Transmission Developers who properly submit their transmission project to be considered for
regional cost allocation (should the sponsor's project be selected in the Regional Transmission
Plan for cost allocation).The biennial cycle includes steps to collect,evaluate and analyze
transmission and non-transmission data,produce and publish a draft plan,gather stakeholder
and public input,update the plan and complete the cycle with the publishing of a RTP.
3 Pursuant to Attachment K,Section Pre-qualify for Cost Allocation,a Project Sponsor that intends to
submit a project for cost allocation must be pre-qualifiedbefore the beginning of the 2016-2017 biennial
planning cycle (i.e.,the last quarterof the prior planning cycle).
NTTG 2016-2017 RegionalTransmission Plan 8NTTGSteeringCommitteeApproval:December 14,2017
Q1-Q4
2016
Q5-Q8
2017
Biennial Study Plan
The biennial study plan outlines the process that NTTG follows to develop its 10-year RTP.It
provides the framework to guide plan development.It also describes NTTG's process to
determine if a properly submitted Interregional Transmission Project (ITP)would yield a
transmission plan that is a more cost-effective or efficient solution to NTTG's regional
transmission needs.
The NTTG PlanningCommittee manages the study plan.The Planning Committee establishes
the Technical Work Group (TWG)subcommittee to develop the study plan.The TWG also
performs the necessary technical evaluations for the RTP and assesses any projects,including
ITPs,submitted to NTTG.TWG members are NTTG Planning Committee members or their
designated technical representatives.They have access to and expertise in power-flow analysis
for power systems or production-cost modeling,or both.
Developed during Quarter 2 of the biennial planning cycle,the study plan establishes the:
Study methodology and criteria
Study assumptions based on the loads,resources,point-to-pointtransmission requests,
desired flows,constraints and other technical data submitted in Quarter 1 and updated
in Quarter 5 of the regional planning cycle
Software analysis tools
2026 production-cost-model database and hours to be selected for reliabilityanalysis
Evaluation criteria for reliabilityand transmission service obligations
Capital cost,energy losses and reserve-sharing metric calculations
Public Policy Requirements and Public Policy considerations
The study plan was posted for stakeholder comment,recommended for approval by the
Planning Committee and approved by the Steering Committee during Quarter 2 of the biennial
NTTG 2016-2017 RegionalTransmission Plan
NTTG Steering Committee Approval:December 14,2017
cycle.Due to data submission updates provided in Quarter 5,the study plan was revised in
Quarter 6.Any differences between what is stated in the study plan and the process stated in
the NTTG Transmission Providers'FERC Order 1000 Attachment K,defer to Attachment K.
Study Methodology
To determine the more efficient or cost-effective transmission plan,the TWG subcommittee
conducted reliabilityand economic studies in accordance with the 2016-2017 Study Plan.The
Study Plan and ultimately the RTP reflect the NTTG Transmission Providers'Attachment K
requirements to satisfy its transmission needs.NTTG's regional transmission planning does not
investigate local transmission planning or generation decisions related to integrated resource
planning.Rather,NTTG's methodology uses a regional perspective to question the Initial RTP's
roll-up of Non-Committed regional transmission project(s)to identify,if possible,a regional
transmission plan that is more efficient or cost effective than the aggregated Full Funder's
transmission plans.In conducting its regional studies,NTTG uses regional transmission and
non-transmission alternatives (if any)to honor the local transmission needs.As part of the
study,NTTG assumed that the local existing and new generation additions have (or will have)
firm transmission rights to move their power from the generator to load.NTTG's reliability
studies did not re-dispatch existing generation down to relieve congestion such that the new
generation additions could move their power to load without potentiallycreating congestion.
The reliabilitystudies used production-cost modeling and power-flow studies.The production-
cost and power-flow models represent data for the western interconnection load,resource and
transmission topology.In developing the data for these two models,NTTG started with a WECC
production cost model (version TEPPC CC1.3)and WECC power-flow model (version 25hsla)
and modified the modeling data in NTTG's footprint for its regional studies.For the studies
including one or more interregional transmission projects that relied on increased wind
generation within NTTG's footprint (e.g.,adding new wind resource in Wyoming),NTTG
adjusted generation levels down in the region receiving the power.The goal of the adjustments
was to ensure western interconnection load and resource balance.NTTG consulted with the
planning region receiving the power (i.e.,California ISO)for their generation reductions.
The results of the production-cost modeling were used to identifyseven hours of high stress on
the transmission system.These seven hours were then subjected to reliabilityanalysis using a
power-flow model.The input and output data for these selected hours were transferred from
the production-cost model (i.e.,GridView)to a power-flow model (i.e.,PowerWorld)to
perform the technical reliabilityanalysis.By taking these steps,a consistent set of analysis tools
and data can be engagedto evaluate the reliabilityperformance.
Next,economic studies employed the Attachment K's three metrics-capital-related costs,
energy losses,and reserves-to analyze Change case plans that were deemed reliable to
further determine the cost effectiveness of the NTTG transmission plan.
NTTG 2016-2017 RegionalTransmission Plan 10NTTGSteeringCommitteeApproval:December 14,2017
The TWG examined 8,760 hours of data using GridView4production-cost software to establish
stressed conditions within the NTTG footprint.To set the stressed conditions,the TWG used
and modified a dataset from the Transmission Expansion Planning Policy Committee (TEPPC)of
the WECC.The TEPPC case included a representation of the load,generation and transmission
topology of the WECC interconnection-wide transmission system 10 years into the future.
The study plan identified seven stressed conditions that affect the NTTG area for study.After all
hours of data were run through the GridView production-cost program,the results were
analyzed and the hours representative of the seven stressed conditions were identified.For a
more detailed discussion of the conditions and hours,see the section on stress-conditioned
case study results.
For the next step in the process,the TWG used PowerWorlds simulation software to convert
the production-cost model for the seven stressed hours into power-flow cases.Each of the
stressed cases was then reviewed by the TWG to ensure that the case met steady-state system
performance criteria (no voltage issues or thermal overloads).Bubble diagrams showing the
inter-area flows for each of the stressed cases are included in the Draft Final RTP,available on
the NTTG website.
Data Submission
Information flows into NTTG during Quarter 1 and Quarter 5 of the biennial cycle.Transmission
Providers and stakeholders may supply data on forecasted firm energy obligations and
commitments required to support the transmission system within the NTTG footprint.The data
may include load forecasts,resources,transmission topology,transmission service and Public
Policy Requirements submissions.Regionaltransmission projects submitted in Quarter 1 are
shown in Table 1 and include those from the prior RegionalTransmission Plan,Transmission
Provider Local Transmission Plans (LTP),Sponsored Projects,unsponsored projects and
Merchant Transmission Developer projects.No projects that were eligible for cost allocation
were submitted into NTTG's 2016-17 regional planning process.
4 GridView is a registered ABB product
6 PowerWorld is a registered trademark of PowerWorld Corp.
NTTG 2016-2017 RegionalTransmission Plan 11NTTGSteeringCommitteeApproval:December 14,2017
SPONSOR FROM TO VOLTAGE TYPE z PROJECTS
DESERETG&T Bonanza Upalco 138 kV 2 LTP No No New Line
LTP &Longhorn Hemingway 500 kV 1 pRTP,Yes No Boardman to Hemingway (B2H)Project
New Line (associated with Boardman toHemingwayBowmont230kV2LTPYesNo.Hemingway)
New Line (associated with Boardman toBowmontHubbard230kV1LTPYesNoHemingway)
IDAHO POWER Gateway West segment #9 (joint withCedarHillHemingway500kV1LTPYesNoPacifiCorpEast)
Cedar Hill Midpoint 500 kV 1 LTP Yes No Gateway West Segment #10
Midpoint Borah 500 kV 1 LTP Yes No (convert existing from 345 kV operation)
King Wood River 138 kV 1 LTP No No Line Reconductor
SE I rta
Star 13D8CkV1L Nes NMeATILi6n0e0
MW Back to Back DC Converter
Aeolus Clover 500 kV 1 LTP &pRTP Yes No Gateway South Project -Segment #2
Aeolus Anticline 500 kV 1 LTP &pRTP Yes No Gateway West Segments 2&3
Anticline Jim Bridger 500 kV 1 LTP &pRTP Yes No 345/500 kV Tie
Anticline Populus 500 kV 1 LTP &pRTP Yes No Gateway West Segment #4
Populus Borah 500 kV 1 LTP Yes No Gateway West Segment #5
PACIFICORPEAST Populus Cedar Hill 500 kV 1 LTP Yes No Gateway West Segment #7
Antelope Goshen 345 kV 1 LTP Yes No Nuclear Resource Integration
Antelope Borah 345 kV 1 LTP Yes No Nuclear Resource Integration
Windstar Aeolus 230 kV 1 LTP &pRTP Yes No Gateway West Segment #1W
Oquirrh Terminal 345 kV 2 LTP Yes Yes Gateway Central
Gateway West Segment #9 (joint with IdahoCedarHillHemingway500kV1LTPYesNoPower)
PACIFICORPWEST Wallula McNary 230 kV 1 LTP Yes Yes Gateway West Segment A
Blue Lake Gresham 230 kV 1 LTP No No New Line
Blue Lake Troutdale 230 kV 1 LTP No No Rebuild
Blue Lake Troutdale 230 kV 2 LTP No No New Line
Horizon Springville Jct 230 kV 1 LTP No No New Line (Trojan-St Marys-Horizon)
PORTLAND Horizon Harborton 230 kV 1 LTP No No New Line (re-terminates Horizon Line)GENERAL Trojan Harborton 230 kV 1 LTP No No Re-termination to Harborton
St Marys Harborton 230 kV 1 LTP No No Re-termination to Harborton
Rivergate Harborton 230 kV 1 LTP No No Re-termination to Harborton
Trojan Harborton 230 kV 2 LTP No No Re-termination to Harborton
Table 1.January 2016 data submittal-transmission additions by 2026.
6 Regionally significant transmission projects are generally those that effect transfer capability between
areas of NTTG.Projects that are mainly for local load service are not regionally significant.Projects that
are not regionally significant will be placed into all change cases and not tested for impact on the
Regional Transmission Plan.The future facilities submitted in the LTP's will be removed in the null case.
*Prior RTP
NTTG 2016-2017 RegionalTransmission Plan 12NTTGSteeringCommitteeApproval:December 14,2017
Forecasted Loads
Participating load-serving entities provide forecasts of loads for balancing authorityareas
internal to the NTTG footprint.These loads are generally the same as those found in the
participants'official load forecasts (such as those in integrated resource plans)and are similar
to those provided to the Load and Resource Subcommittee of the WECC Planning Coordination
Committee.Figure 3 summarizes the load forecast used in the 2016-2017 planning cycle.
2026 NTTG FORECASTED LOADS
TOTAL MW
201 22,122
202DA
A 23,902
DATUA
U 23,637
2026 SUMMER LOAD
DATA SUBMITTED 23,620
INQ52017(MW)
DIFFERENCE(MW)-2822024-2026
Idaho NorthWestern PacifiCorp Portland
Power Energy -588 General
147 218 -59
Figure 3.2026 NTTG forecasted loads
NTTG received 3,200 MW of proposed new generation resources from its funding Transmission
Providersfor consideration in the RTP.Figure 4 displays these incremental resources within the
NTTG footprint and compares submissions from the prior RTP with submissions for Quarter 1
and Quarter 5 of the current cycle.
NTTG 2016-2017 RegionalTransmission Plan 13NTTGSteeringCommitteeApproval:December 14,2017
COMPARISON OF FORECASTED RESOURCES (MW)
NATURAL GAS
WIND
60BIOMASS4
4
o 2024
GEO-THERMAL 10
|10 2026 Q1
-81 |2026 Q5
133
124
NUCLEAR
MARKET/OTHER
Figure 4.Comparison of forecasted resources.
In the 2014-15 study cycle,Power Company of Wyoming (PCW)submitted 3,000 MW of wind
resources associated with the TransWest Express project.PCW asked that those resources not
be included in the NTTG 2014-15 Regional Plan,and those resources have been shown
separately in Figure 4.For the 2016-17 study cycle,the 3,000 MW has been excluded from the
NTTG totals.Those resources,to serve loads outside the NTTG footprint in California,have
been submitted with an Interregional Transmission Project in the 2016-17 study cycle.
In Quarter 5,NorthWestern submitted 550 MW of new Montana wind generation.Also
PacifiCorpindicated that its recently submitted integrated resource plan increased the amount
of Wyoming wind power from 887 MW to 1,100 MW.As shown in Figure 4,the total resource
forecast of 3,200 MW submitted this cycle was reduced by 1,516 MW,or 32.1 percent,from
the 4,716 MW forecast in 2024.Following the Quarter 1 data submittal,the owners of the
Colstrip 1 and 2 coal-fired plants announced a plan to retire the units before 2026.The owners
of the Valmy 1 and 2 coal plants in Nevadaalso plan to decommission the plants by 2025,a
NTTG 2016-2017 RegionalTransmission Plan 14NTTGSteeringCommitteeApproval:December 14,2017
decade earlier than originally planned.Both sets of retirements were assumed in the 2016-
2017 studies and are reflected in Quarter 5 values shown in Figure 4.
In support of the proposed transmission additions or upgrades,NTTG received four firm
transmission-service-obligation submissions (contractual requirements to provide service)-
two each from Idaho Power and PacifiCorp.These are shown in the following map.
Washington
*·,L ..Montana
Oregott Wyoming
California
Nevada .Colorado
Utah
Figure 5.Transtnission Service Obligations.
Public Policy Consideration Scenario Requests
In Quarter 1,Renewable Northwest (RNW)and the Northwest Energy Coalition (NWEC)jointly
submitted a Public Policy consideration request for a scenario analysis study.The group asked
NTTG to study a faster phase-out of coal plants while developing utility-scale renewable
resources and replacing Colstrip units 1,2 and 3 with either wind only or a combination of wind
and natural gas simple/combined cycle resource.
Members of the TWG and representatives from RNW and NWEC reviewed the request and
agreed to some modifications.These modifications,and the associated study assumptions,are
documented in the NTTG 2016-2017 Study Plan,Attachment 3 of the Draft Final RTP.
NTTG 2016-2017 RegionalTransmission Plan 15NTTGSteeringCommitteeApproval:December 14,2017
The study results suggestedthat a replacement of wind or a combination of wind and gas for
coal may be feasible.This study,however,neither constituted a path study nor conveyed or
implied transmission rights.Additional analysis would be required to understand the full
impacts of coal plant decommissioning.
Public Policy Considerations are considered to be relevant factors not established by local,state
or federal laws or regulations.The results of PPC analysis may inform the RTP but do not result
in the inclusion of additional projects in the RTP.
A full report of the study can be found in Appendix D of the NTTG 2016-2017 Draft Final RTP.
Regional Economic Study Requests
NTTG received no regional economic study requests.
Initial Regional Transmission Plan Development
The starting point for the biennial planning process was development of the Initial RTP.This
exercise used a bottom-up approach to merge the projects in the prior RTP (2014-2015)and
the NTTG Transmission Providers'local transmission plans into a single regional transmission
plan.Next,the TWG analyzed the Initial RTP through Change Case plans,which included or
excluded Non-Committed regional projects and Interregional Transmission Projects.These
Change Case plans helped to determine whether Alternative Projects could be added or
substituted,or if one or more Non-Committed Projects could be deferred,or both,to yield a
regional transmission plan more efficient or cost effective than the Initial RTP.The results of
this analysis led to the formation of the Draft RTP.
NTTG 2016-2017 RegionalTransmission Plan 16NTTGSteeringCommitteeApproval:December 14,2017
Washington
Idáho
Wyoming
Nevada
Figure 6.The turquoise and green lines represent the projects comprising the prior RTP from 2014-2015.These
include Boardman to Hemingway,in the northwest sector of the above map,and an Alternative Project with four
transmission elements across four states.
Idaho
Wyoming
Nevada
Figure 7.Map showing Non-Committed regional projects comprising the 2016-2017
Initial RTP.-Boardman-Hemingway
-Gateway West
-Gateway South
-Antelope
NTTG 2016-2017 RegionalTransmission Plan 17NTTGSteeringCommitteeApproval:December 14,2017
Interregional Project Coordination
As part of interregional coordination,NTTG and the other regional entities in the Western
Interconnection collaborate during their transmission planning processes to coordinate their
interregional transmission planning data.These coordination efforts inform each planning
region's transmission plans.A properly submitted Interregional Transmission Project is
evaluated as an Alternative Project in NTTG's regional planning process.The set of
uncommitted projects (regional,interregional or both)that result in the more efficient or cost-
effective plan forms the Regional Transmission Plan.
SUMMARY OF Q1-2016 INTERREGIONAL
PROJECTS SUBMITTED TO NTTG
PROJECTNAME COMPANY TERMINATION TO
RRA
S
IESSION
PROJECT TransCanyon,LLC Wes ect Clover UT RobinsoNn Summit'Conceptual 2024
SWIP-NORTH Tra
emat sn
LLC Wes ect Midpoint,ID RobinsoNn Summit'Permitted 2021
R
IESSSOENPRRESSECTTransWeLLCExpress'Waes ect Sinclair,WY Boulder City,NV Conceptual 2020
Table 2.Three Interregional Transmission Projects were submitted for consideration during formation of the Initial
RTP in Quarter 1 of the biennial cycle.
NTTG 2016-2017 RegionalTransmission Plan 18NTTGSteeringCommitteeApproval:December 14,2017
Idaho
Wyoming
CROSS-TIE \\
TRANSWEST
EXPRESS
Utah Colorado
Arizona
Southwest Intertie Project (SWIP).Great Basin Transmission,LLC (GBT),an affiliate of LS
Power,submitted the 275-mile northern portion of the Southwest Intertie Project (SWIP)as an
ITP.SWIP-Northwould connect the Midpoint500-kV substation in NTTG's planning area to the
RobinsonSummit 500-kV substation in the Westconnect area with a 500-kV single-circuit AC
transmission line.The SWIP is expected to have a bi-directional WECC-approvedpath rating of
approximately 2,000 MW.If GBT is selected to build SWIP-North,development,final design and
construction activities could be completed to support energizing the project within an
estimated 36-42 months.
Cross-TieTransmission Line.TransCanyonsubmitted the 213-mile Cross-Tie Transmission Line
for consideration as an ITP.TransCanyonproposes to build a 1500-MW,500-kV high-voltage
alternating current (HVAC)line between central Utah and east-central Nevada.The line would
connect PacifiCorp's proposed 500-kV Clover substation with the existing 500-kV Robinson
Summit substation.Transcanyon expects the project to be in-service by the end of 2024.
TransWest Express Transmission Project.TransWest proposed a 730-mile,phased
1,500/3,000 MW,±600 kV,high-voltage direct current (HVDC)transmission system with
terminals in south-central Wyoming and southeastern Nevada.The federal Bureau of Land
Management and Western Area Power Administration published the Final Environmental
Impact Statement (FEIS)for the TWE Project in May 2015.
NTTG 2016-2017 RegionalTransmission Plan 19NTTGSteeringCommitteeApproval:December 14,2017
Stress-conditioned Case Study Results
Stressed Hours for Study with Production-CostModeling
The TWG used GridView production-cost software to review 8,760 hours of data to identify
stressed conditions within the NTTG footprint.A case representing the year 2026 was obtained
from the WECC TEPPC.This case included a representation of the load,generation and
transmission topology of the WECC interconnection-wide transmission system 10 years in the
future.The TWG identified corrections to the data needed to align with data submitted in the
first quarter of the biennial planning cycle.The TWG shared these changes with the other
regional planning entities and WECC to include in their future studies.The TWG then agreed to
use this modified TEPPC case in creating the stressed cases discussed below.
After processingall 8,760 hours through the production-cost program,the TWG analyzed the
data and identified seven stressed conditions to study,as shown in Table 3.
STRESSED CONDITION TWG LABEL
Max.NTTG Summer Peak July 22,2026 16:00 A
Max.NTTG Winter Peak December 8,2026 19:00 B
Max.MT to NW September 10,2026 Midnight C
High Southern Idaho import June 11,2026 14:00 D1
High Southern Idaho Export September 17,2026 2:00 D2
High Tot2 Flows November 11,2026 17:00 E
High Wyoming Wind September 17,2026 2:00 F
Tab e 3.Hours selected from 2026 WECC TEPPC case to represent different NTTO system stresses.
High Summer Peak (NTTG Case A)
24,100 MW load
17,851 MW resources
6,250 MW import
4 p.m.,July 22,2026
This case showed a need to import energy during high summer air-conditioning loads.The
transmission projects in the initial RTP performed reasonably well;however,system
performance proved inadequate without transmission system additions by 2026 to meet
NTTG's summer peak load.This case accounted for wind resources of 2,175 MW to check the
performance of the set of projects comprising the Draft RTP.
NTTG 2016-2017 RegionalTransmission Plan 20NTTGSteeringCommitteeApproval:December 14,2017
High Winter Peak (NTTG Case B)
22,468 MW load
19,261 MW resources
3,208 MW import
7 p.m.,Dec.8,2026
A few local system violations occurred when tested against the transmission projects
comprising the Initial RTP.This case puts less stress on the NTTG system than did the summer
peak.This case also accounted for wind resources of 2,175 MW to check the performance of
the Draft RTP projects.
High Montana-NW (Path 8)Flows (NTTG Case C)
13,097 MW load
12,138 MW resources
959 MW import
12:00 midnight,Sept.10,2026
This case tested transmission system capabilities with high electricity flows from Montana to
the Northwest.This scenario was used for the Public Policy Consideration study,which
analyzed the impact of an accelerated phase-out of Colstrip units 1,2 and 3 with either wind
only or a combination of wind and gas.See the Public Policy consideration Scenario Requests
section for results of the study.
High Southern Idaho Import (NTTG Case D1)
16,382 MW load
9,159 MW resources
7,223 MW import
2 p.m.,June 11,2026
Under conditions with the eastbound path from the Northwest to Idaho operating at a 2,244
MW deficit,and the NTTG system importing 7,223 MW,the NTTG transmission topology could
not import enough power to support load service obligations in southern Idaho.With the
addition of transmission projects comprising the Initial RTP,however,the NTTG system would
perform well,with a few local violations.
High Southern Idaho Export (NTTG Case D2)
11,935 MW load
14,683 MW resources
2,748 MW export
2 a.m.,Sept 17,2026
NTTG 2016-2017 RegionalTransmission Plan 21NTTGSteeringCommitteeApproval:December 14,2017
In this export scenario,with the Idaho to Northwest Path 8 flow at 3,391 MW,the existing
NTTG system would be incapable of supporting expected transfers and meeting transmission
requirements in 2026.Adding in the projects from the Initial RTP,the system performed well,
with one contingency that caused a series capacitor bank to overload.That bank,however,has
reached the end of its useful life and is likely to be replaced before 2026.
High NE-SE (Path Tot2)flows (NTTG Case E)
16,625 MW load
16,620 MW resources
5 MW export
5 p.m.,Nov.11,2026
This case evaluated the performance of the Interregional Transmission Projects in supporting
transfers between regions.These additional interregional transfers were not identified in Q.1to
meet or defer NTTG's 2026 footprint resource requirements.The case showed near balance in
the NTTG footprint between loads and resources,with a small 5 MW import,along with a Tot2
flow of 1,566 MW.This case accounted for wind resources of 2,175 MW to check the
performance of the Draft RTP.
High Wyoming wind production (NTTG Case F)
11,935 MW load
15,015 MW resources
3,081 MW export
2 a.m.,Sept.17,2026
This case,as others,was studied at the 2,175-MW wind level,which includes the addition of
1,100 MW of wind capacity.The thermal dispatch in this case was at a typical high level of
3,580 MW.The added wind generation in the Wyoming area worsened reliability issues
observed in Wyoming and confirmed the need for additional transmission to use these
resources to their fullest extent.The RTP addresses these reliabilityconcerns and relieves the
transmission constraints.
Developmentof Change Cases
For each of the seven stress-conditioned cases,the TWG prepared a null change case and
analyzed reliabilityresults.The null case represents roughly today's transmission topology
made to serve loads and resource requirements in 2026.Only the HeavyWinter case
performed acceptably.All the other conditions revealed performance issues that required
varying degrees of correction,with the heavy summer case needing the least correction and
the high Wyoming wind case needing the most.In instances where the transmission system
was not adequately stressed to historical norms,the TWG slightly modified system conditions
to ensure that the transmission system was studied under reasonably stressed conditions.
NTTG 2016-2017 RegionalTransmission Plan 22NTTGSteeringCommitteeApproval:December 14,2017
Change Case Results
To efficiently study the wide range of potential combinations of Non-Committed Projects,the
TWG proposed a change case matrix in the study plan.Once the stressed power-flow cases
had been selected and developed,the TWG modified the matrix to better reflect the
recommended analysis.The TWG provided stakeholders with the opportunity for input on
whether a particular combination of uncommitted regional or interregional projects should be
analyzed.No comments were received.The matrix was subsequently vetted through the
Planning Committee and the Steering Committee.
Figure 9 is the change case matrix used by the TWG.
NTTG 2016-2017 RegionalTransmission Plan 23NTTGSteeringCommitteeApproval:December 14,2017
CHANGE CASE MATRIX
STRESSEDCASECONDITIONS
ABD1D2F
X X d ABD1D2F
X X X X ABD1D2EF
X ABD1D2F
X X AD2EF
X X ABD1D2EF
X X X ABD1D2EF
X ABD1D2F
X ABD1D2F
X ABD1D2F
X E+RPS
X X E+RPS
X X X E+RPS
X E+RPS
X X E+RPS
X X X
X E+RPS
X X E+RPS
X X X
X X X X E+RPS
X X X E+RPS
X X X E+RPS
X X X X X
X X a X
X X b X
X X c X ABD1D2EF
*B2H and Alternate Project in the pRTP are similar to B2H,GatewayS and GatewayW in the2016-17 Q1data submittals
The change case does not includethe non-Committed Project
X The change case includes the non-Committed Project
a GatewayWest without Midpoint-Hemingway#2 and Cedar Hill-Midpoint
b GatewayWest without Borah-Midpoint Uprateand Populus-Borah
GatewayWest without Midpoint Hemingway#2,Cedar Hill-Midpoint and Populus-Borah
d GatewayWest without Midpoint Hemingway#2,Cedar Hill-Midpointand Populus CedarHill-Hemingway Populus-Borahand Midpoint-Borah Uprate
The change case was runwith and without B2H
Figure 9.Change Case matrix used in the development of the RTP.
In all,the TWG performed more than 100 reliabilitystudies with more than 410 contingencies
in each study.To better communicate the results of these studies,the TWG created heat maps,
NTTG 2016-2017 RegionalTransmission Plan 24NTTGSteeringCommitteeApproval:December 14,2017
which present a weighted"graphical performance of a change case on a specific flow
condition.A full heat map analysis of the Change cases is included in the final Draft RTP.
Washington Montana
Oregon Idaho
Wyoming
Nevada Utah
Colorado
California
Ngure 10,Heat map of the D2-Null Case
Figure 10,for example,shows the general location where performance issues (e.g.,an
overloaded transmission line)occurred for a contingency.The accumulation of overloads and
voltage issues are represented by the color spectrum from blue to red,or "cooler"to "hotter."
These violations occur when transmission systems cannot handle anticipated transfers across
that area's transmission lines.In particular,this heat map,using existing Wyoming wind
resources dispatched at about 600 MW,indicates that transmission additions are necessary to
integrate the projected wind resources.
3 High voltage conditions had a weighting of 1;low-voltageconditions had a weighting of 3;and
overloads of branches had a weighting of 5.For example,a zone in which 10 contingencies caused an
overload of one branch in that zone would receive a total weight of 50 (i.e.,10 x 5),which would then be
translated into a color on the map.A blue color represents a weighted total of about 10,green is a count
up to 30,yellow is a count up to 50 and red is for a weighted count exceeding about 70.
NTTG 2016-2017 RegionalTransmission Plan 25NTTGSteeringCommitteeApproval:December 14,2017
Washington Montana
Oregon
Wyoming
California
Nevada
Utah
Colorado
The heat map in Figure 11 shows how the addition of the Initial RTP projects produced a
dramatic improvement of transmission performance when compared with the null case.
Combining the Boardman to Hemingway project with the Gateway West and Gateway South
Non-Committed Projects eliminated violations in flow conditions visible in the null case.Change
Case 3 tested whether Gateway West or Gateway South,or both,could replace or compare
with the Boardman to Hemingway line.They couldn't.The projects contained in the prior RTP
also failed to alleviate the violations.
Adding the Boardman to Hemingway project relieved stress across the Idaho-Northwest
cutplane,but significant issues remained east of Hemingway.Adding the eastern portion of
Gateway West and Gateway South outlined in the prior RTP eliminated the performance issues
in Wyoming and between Idaho and Montana,but those additions increased the stress across
southern Idaho.The Initial RTP and Change cases 21 and 23 resolved these issues.
Without significant reinforcements,the transmission system in Wyoming could not handle both
existing and future planned wind resources while maintaining all other Wyoming area
generating resources at their typical high capability in an export scenario.
NTTG 2016-2017 RegionalTransmission Plan 26NTTGSteeringCommitteeApproval:December 14,2017
With wind production at the 1,300-MW level in the null case (no new transmission supporting
2026 loads),the system performed poorly.Nor did the projects in the prior RTP solve problems.
Adding the Initial RTP projects resolved all violations except for a series capacitor bank.That
bank has reached the end of its useful life,however,and is due for replacement.
In O.uarter6,the case was tested to see if Change cases 1through 4 would support the
increased level of Wyoming wind.The null case (no new transmission)was unable to be solved
with wind above 1,800 MW.Testing Change Case 4 required adding the Aeolus-Anticline 500-
kV line (Case 4a)to eliminate a number of contingencies that failed to solve in Wyoming.
Change Case 23,which is essentially change Case 4a with Gateway South added,performed
well with Wyoming wind modeled at 2,175 MW.
Change Cases 5 through 20 tested whether the three Interregional Transmission Projects
(ITP)-alone,in combination with other ITPs or in combination with the Non-Committed
Projects-could satisfy NTTG's transmission needs on a regional or interregional basis more
efficiently or cost effectively than through local planning processes.The ITPs were added to the
null cases without any additional resources to serve NTTG load beyond those resources
identified in the Quarter 1 and Quarter 5 data submittals.Testing showed the ITPs did not
provide the NTTG footprint with regional benefits,either by significantly reducing performance
issues or by displacing NTTG Non-Committed Projects.
The Initial RTP also was analyzed to determine whether it would be capable of supporting the
interregional resource transfers proposed by the ITPs.Given the relatively long distances of the
ITPs,the local integration performance issues identified in Wyoming were solvable.
Reliability Conclusions
Based on the above study results,the TWG concluded that the Initial RTP shown in Figure 7 and
two variants,Change cases 21and 23,satisfy NTTG reliabilitycriteria.In Q.uarter5,the TWG
tested Change case 23 and the wind resource additions at various load and flow levels on the
HeavySummer,HeavyWinter,High Tot2 and High Wyoming wind cases.The TWG study found
the NTTG area would be reliably served in the year 2026 only by including the following Non-
Committed regional projects:
Boardman to Hemingway
The Energy Gateway projects including segments:
Windstar-Aeolus 230 kV
Aeolus-Clover 500 kV
Aeolus-Anticline 500 kV
Anticline-Populus 500 kV
Populus-CedarHill-Hemingway 500 kV
NTTG 2016-2017 RegionalTransmission Plan 27NTTGSteeringCommitteeApproval:December 14,2017
Borah-Midpoint 345 kV uprate to 500 kV
Antelope Transmission Project including:
Antelope-Borah 345 kV
Antelope-Goshen 345 kV
Antelope 345/230 kV transformers and interconnection facilities
The ITPs were evaluated to determine whether one or more of them could defer or replace
NTTG's Non-Committed Projects.TheTWG concluded that none of the ITPs solved NTTG's
reliability performance issues and,thus,were not included in the Draft Final NTTG RTP.
Economic Evaluations
To determine whether the Initial RTP or a Change case transmission plan was more cost
effective,the TWG used three economic metrics,as determined in the biennial study plan.The
three metrics-capital-related costs,power flow losses and reserves-and results are discussed
below.
Development of the capital-related cost metric required three steps.The first step validated
the capital cost of the Project Sponsor's O,1 submitted project.The second step used those
results to estimate the annual capital-related costs.The third step levelized the net present
value annual capital-related costs for the Initial RTP and the change case plans.
The energy-loss metric captures the change in energy generated,based on system topology,to
serve a given amount of load.A reduction in losses for a change case would represent a
benefit,since less energy would be required to serve the same load.The two change cases
with fewer Gateway West transmission segments-Change Cases 21 and 23-had losses higher
than,or in some cases equal to,the Initial RTP.Losses were higher in the two change cases
because the electrical flows in the Initial RTP were redistributed to fewer lines.From a loss
perspective alone,the Initial RTP case had fewer losses and as such was the more efficient
case.
The reserve metric evaluates the opportunities for two or more parties to save money by
sharing a generating resource that would be enabled by transmission.The metric is a 10-year
look at the increased load and generation additions in the NTTG footprint and the incremental
transmission additions that may be included in the RTP.
In the study cycle,the TWG analyzed Gateway West,Gateway South,Boardman to Hemingway,
SWIP North and the Cross-Tie projects.To evaluate these projects,the NTTG footprint was
segmented into five zones,and a sixth external zone was included to study the SWIP North and
the Cross-Tie projects.The six zones produced 122 viable sharing combinations.Of those,the
NTTG 2016-2017 RegionalTransmission Plan 28NTTGSteeringCommitteeApproval:December 14,2017
analysis of the annual net savings over each theoretical participant's standalone alternative
suggested that only 34 viable combinations were economic.
Note that this metric includes generation capital costs in its evaluation and,as such,may only
be appropriate for cost allocation purposes.It should not drive the selection of a RTP.Whether
these cost savings warrant jointlysharing the costs of reserve capacity is up to the parties to
decide.
For the NTTG metric analysis,the Initial RTP and the two alternative Change cases each
supported viable economic combinations.Since these Change cases could contain the same
benefit value,the change in Reserve metric did not factor into the RTP selection decision.
Economic Metric Analysis Conclusion
The sum of the annual capital-related cost metric,loss metric (monetized)and reserve metric
(monetized)yielded an incremental cost for the Initial RTP and the Change case plans.The set
of projects with the lowest incremental cost,after adjustment by the plan's effects on
neighboring regions-Change case 23 (see Figure 10,below)-was then incorporated into the
RTP.Note that the incremental cost was computed as the levelized annual capital-related cost,
minus NTTG loss benefit,minus monetized reserve benefit.
INCREMENTAL COST
$1,000 $801 $836 $899
$800
$600
$400
$200
$0.0
MILLIONs CC23 CC21 IRTP
Figure 12 Change Case 23,comprising Boardman to Hemingway,Gateway South,portions of GateiNay VJest,and
the Antelope projects,produced the lowest incremental cost.
Final Regional Transmission Plan
Based on the study assumptions and reliabilityand economic conclusions discussed above,the
more efficient or cost-effective plan is Change Case 23.Change Case 23 is a staged variant of
the Initial RTP.For the transfers submitted in Quarter 1 and Quarter 5,the facility segments
NTTG 2016-2017 RegionalTransmission Plan 29NTTGSteeringCommitteeApproval:December 14,2017
shown in Figure 13,below,were not necessary for the transfers studied in the Change cases.
These segments would likely be necessary at higher transfer levels.
I
IdahoMIDPOINT-HEMINGWAY#2
500KV
CEDAR HILL-MIDPOINT
500KV
POPULUS-BORAH
500KV
Figure 13.These transmission line segments from the Initial RTP were not included in the final RTP.
NTTG's final RTP emerged after a rigorous reliabilityanalysis of the NTTG Transmission
Providers'rollup of their local area plans and assumption of Non-Committed regional
transmission projects,augmented with stakeholder Interregional Transmission Projects.This
technical analysis was followed by an economic metric analysis that selected NTTG's more
efficient and cost-effective regional transmission plan,shown below in Figure 14.
Montana
Idaho
Wyoming
Oregon
Utah
Nevada
Figure 14.These projects comprise NTTG's final RTP.
-Boardman-Hemingway
-Gateway West (from 300kV to 500kV)
-Antelope
Gateway West
-Gateway South
NTTG 2016-2017 RegionalTransmission Plan 30NTTGSteeringCommitteeApproval:December 14,2017
Cost Allocation
The SWIP-North Project Sponsors were the only Project Sponsors to request cost allocation;
however,they failed to comply with the requirement to submit pre-qualification data by Oct.
31,2015.As a result,no projects that were eligible for cost allocation were submitted into
NTTG's 2016-17 regional planning process.
Next Steps
Publication of the NTTG Regional Transmission Plan completes the two-year planning process
begun with pre-qualification of Project Sponsors in Quarter 8 2015 and continued with project
data submittal in Quarter 1 of 2016.The NTTG 2016-2017 RTP identified a need for new
transmission capacity to serve forecasted load in 10 years.The plan also identified a set of
transmission projects known in this report as change case 23 as the more efficient or cost-
effective transmission plan to meet that need.While the RTP is not a construction plan,it
provides valuable regional insight and information for all stakeholders (including developers)to
consider and use in their respective decision-making processes.
The next biennial regional transmission planning cycle for NTTG started Oct.1,2017 with
Project Sponsorpre-qualification and will culminate with the publication of the 2018-2019 RTP
in December 2019.
NTTG 2016-2017 Regional Transmission Plan Supporting Materials
The supporting materials referenced in this report have been posted on the NTTG website and
can be found using the following link:
https://www.nttg.biz/site/index.php?option=comdocman&view=list&slug=supporting-
documents-regional-transmission-plan&ltemid=31
A list and link to each of the individual supporting documents is also provided below:
1.Amended O,uarter6 NTTG 2016-17 Biennial Study Plan Approved 08-02-2017
2.NTTG 2016-2017 Draft Final RegionalTransmission Plan -06-30-2017
3.NTTG 2016-2017 Public Policy Consideration Scenario Report
Glossary
Note:This Glossary is for the benefit of readers and neither supplements nor modifies any
defined terms contained in any entity's filed Open Access Transmission Tariff (OATT),including
the Attachment K to that tariff.To the extent that a term divergesfrom any entity's OATT,the
OATT takes precedence.
NTTG 2016-2017 RegionalTransmission Plan 31NTTGSteeringCommitteeApproval:December 14,2017
Alternative Project Alternative Project refers to Sponsored Projects,projects submitted by
stakeholders,projects submitted by Merchant Transmission Developers and unsponsored
projects identified by the Planning Committee (if any).
ChangeCase A Change Case is a scenario where one or more of the Alternative Projects is
added to or replaces one or more Non-Committed projects in the Initial RTP.The deletion or
deferral of a Non-Committed Project in the Initial RTP without including an Alternative Project
can also be a change case.
Committed Project A Committed Project is a project that has all permits and rights of way
required for construction,as identified in the submitted development schedule,by the end of
Quarter l of the current regional planning cycle.
Draft Regional Transmission Plan Draft RegionalTransmission Plan refers to the version of the
RegionalTransmission Plan that is produced by the end of Quarter 4 and presented to
stakeholders for comment in Quarter 5.
Draft Final Regional Transmission Plan Draft Final RegionalTransmission Plan refers to the
version of the Regional Transmission Plan that is produced by the end of Quarter 6,presented
to stakeholders for comment in Quarter 7 and presented,with any necessary modifications,to
the Steering Committee for adoption in Quarter 8.
Initial Regional Transmission Plan Initial RegionalTransmission Plan comprises projects
included in the prior Regional Transmission Plan and projects included in the Full FundersLocal
Transmission Plans and accounts for future generation additions and deletions (e.g.,
announced coal retirements).
InterregionalTransmission Project An Interregional Transmission Project is a proposed new
transmission project that would directly interconnect electrically to existing or planned
transmission facilities in two or more planning regions and that is submitted into the regional
transmission planning processes of all such planning regions.
Merchant Transmission Developer Merchant Transmission Developer refers to an entity that
assumes all financial risk for developing and constructing its transmission project.A Merchant
Transmission Developer recovers the costs of constructing the proposed transmission project
through negotiated rates instead of cost-based rates.
Non-Committed Project A project that is not a Committed Project
Project Sponsor A Project Sponsor is a Non-incumbent Transmission Provider or Incumbent
Transmission Provider intending to develop the project that is submitted into the planning
process.
Public Policy Consideration Those public policy considerations that are not established by local,
state,or federal laws or regulations.
NTTG 2016-2017 RegionalTransmission Plan 32NTTGSteeringCommitteeApproval:December 14,2017
Public Policy Requirements Those public policy requirements that are established by local,
state or federal laws or regulations,meaning enacted statutes (i.e.,passed by the legislature
and signed by the executive)and regulations promulgated by a relevant jurisdiction.
Sponsored Project A Sponsored Project is a project proposed by a Project Sponsor.
NTTG 2016-2017 RegionalTransmission Plan 33NTTGSteeringCommitteeApproval:December 14,2017