Southwest Transmission Cooperative, Inc.
Available Transfer Capability Implementation Document Procedure
Version 5
Table of Contents
1.
INTRODUCTION .............................................................................................................. 3
2.
ATC METHODOLOGY………...………………………………………………………..3
3.
RESPONSIBILITY……………………………………………………………………….3
4.
REFERENCES……………………………………………………………………………3
5.
INTERVALS AND UPDATE FREQUENCY……………………………………………3
6.
DETERMINATION OF TTC……………………………………………………………..4
7.
FIRM ATC CALCUATION METHODOLOGY………………………………………...7
8.
NON-FIRM ATC CALCUATION METHDOLOGY…………………………………….8
9.
IMPLEMENTATION……………………………………………………………………..8
10.
ETC CALCULATION…………………………………………………………………...10
11.
COUNTERFLOW……………………………………………………………………….12
12.
GENERATION AND TRANSMISSION OUTAGE……………………………………12
13.
DETERMINATION OF CBM AND TRM……………………………………………...13
14.
POSTBACKS……………………………………………………………………………13
15.
DATA RETENTION…………………………………………………………………….14
16.
REQUESTS FOR DATA………………………………………………………………..14
17.
VERSION HISTORY……………………………………………………………………15
APPENDIX A - RATED PATH NUMBERS
APPENDIX B - RATED PATH METHODOLOGY (AVAILABLE UPON REQUEST)
APPENDIX C - MARCH 4, 2011 LETTER FROM NERC
APPENDIX D – ATC DATA TO BE PROVIDED UPON REQUEST
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1.
INTRODUCTION
Southwest Transmission Cooperative, Inc. (SWTC), a Transmission Operator and
Transmission Service Provider, has prepared this Available Transfer Capability
Implementation Document (ATCID) as required by the North American Reliability
Corporation (NERC) Standard MOD-001-1a. This ATCID for SWTC contains
information relative to SWTC’s methodology for determining Total Transfer Capability
(TTC), Available Transfer Capability (ATC) and additional requirements from MOD-029001-1a (Rated System Path Methodology).
2.
ATC METHODOLOGY
SWTC has selected the NERC Rated System Path Methodology as the appropriate
methodology to use to determine the TTC and the ATC for the SWTC transmission system.
(MOD-001-1a, R1) This document contains the documentation of SWTC’s methodology
and assumptions for determining TTC and ATC. SWTC shall use the ATC and TTC as
determined within this document for all determinations of ATC and TTC. (MOD-001-1a
R6 and R7)
3.
RESPONSIBILITY
The following SWTC positions are responsible for implementing the methodology set forth
in this document:
Transmission Planning Manager
Director of System Operations
These positions are responsible for implementing the methodology described within this
document.
4.
REFERENCES
NERC Reliability Standard MOD-001a-1
NERC Reliability Standard MOD-029a-1
5.
INTERVALS AND UPDATE FREQUENCY
SWTC posts the ATC for each ATC Path through OATI OASIS based on the calculations
performed in WebTrans from the components of the ATC algorithms as discussed within
this ATCID. SWTC’s calculation of ATC is performed and values are updated
automatically for the intervals listed below and whenever the WebTrans tool detects a
change in the value of any component within the ATC algorithm.
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SWTC’s calculated ATC values are updated by WebTrans for the intervals and frequency
as outlined below: (MOD-001-1a R2.1, 2.2, 2.3)
Hourly values for the next seven days. (Recalculated each hour or as changes are made to
affect the ATC calculation) (MOD-001-1a R8.1)
Daily values for the next 31 calendar days. (Recalculated each day or as changes are made
that affect the daily ATC calculation) (MOD-001-1a R8.2)
Weekly values for five weeks. (Recalculated each day or as changes are made that affect
the weekly ATC calculation)
Monthly values for the next 12 months (months 2-13). (Recalculated each day or as
changes are made that affect the monthly ATC calculation) (MOD-001-1a R8.3)
6.
DETERMINATION OF TTC
At least annually SWTC shall use the following process to determine TTC:
Except where otherwise specified within NERC Reliability Standard MOD-029-1a, adjust
base case generation and load levels within the updated power flow model to determine the
TTC (maximum flow or reliability limit) that can be simulated on the ATC Path while at
the same time satisfying all planning criteria contingencies as follows: (MOD-029-1a
R2.1)
During TTC studies, SWTC recognized NERC’s consideration of MOD-029-1a R2.1 by
the letter from NERC to Transmission Operators and Transmission Service Providers
subject to MOD-029-1a, dated March 4, 2011 (Appendix D).
R2.1 – Except where otherwise specified within MOD-029-1, adjust base case
generation and Load Levels within the updated powerflow model to determine the TTC
that can be simulated on the ATC path while at the same time satisfying all planning
criteria contingencies as listed below. If a reliability limit can be found in simulation,
the TTC is set to the simulated flow on the ATC Path corresponding to the reliability
limit. If no reliability limit is found in the simulation, the TTC may be set equal to the
Facility Rating of the path or the maximum simulated flow on the path.
Flow Limited Definition: A path is “flow limited” if the simulated flow, at the established
transfer level, on the path is less than the facility rating, and new reliability limits have
been found.
A reliability limit is found if contingency results in a violation of a Facility Rating or SOL
on the ATC Path being rated or an outage of any element of the ATC Path being rated
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results in a criteria violation on any part of the system. If a reliability limit is not found in
the simulation, the TTC is set to either a) the simulated flow or b) the Facility Rating.
SWTC also followed NERC’s recommendation (refer Appendix D, NERC letter dated
March 4, 2011) to calculate TTC consistent with past practices. The methodology
incorporating the proposed R2.1 language was used to provide evidence of “flow limited”
paths.
In the interim, NERC suggests (but does not require) that entities calculate the TTC
of “Flow Limited” paths consistent with practices used in the past (such as using
the path thermal rating). During audits, any paths for which TTC has not been
calculated based on R2.1 will be expected to be demonstrably “Flow Limited”.
Evidence to demonstrate this will be considered on a case by case basis, but in
general, a presentation of the studies showing the results of the simulation will be
adequate proof of compliance.
When modeling normal conditions, all Transmission Elements will be modeled at or below
100% of their continuous rating. (MOD-029-1a R2.1.1)
When modeling contingencies the system shall demonstrate transient, dynamic and voltage
stability, with no Transmission Element modeled above its Emergency Rating. (MOD029-1a R2.1.2)
Uncontrolled separation shall not occur. (MOD-029-1a R2.1.3)
Where it is impossible to actually simulate a reliability-limited flow in a direction counter
to prevailing flows (on an alternating current Transmission line), set the TTC for the nonprevailing direction equal to the TTC in the prevailing direction. If the TTC in the
prevailing flow direction is dependent on a Special Protection System (SPS), set the TTC
for the non-prevailing flow direction equal to the greater of the maximum flow that can be
simulated in the non-prevailing flow direction or the maximum TTC that can be achieved
in the prevailing flow direction without use of a SPS. (MOD-029-1a R2.2)
For an ATC Path whose capacity is limited by contract, set TTC on the ATC Path at the
lesser of the maximum allowable contract capacity or the reliability limit as determined by
2.2.1. (MOD-029-1a R2.3)
For an ATC Path whose TTC varies due to simultaneous interaction with one or more other
paths, develop a nomogram describing the interaction of the paths and the resulting TTC
under specified conditions. SWTC does not currently have any paths requiring
nomograms. (MOD-029-1a R2.4)
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SWTC shall identify when the TTC for the ATC Path being studied has an adverse impact
on the TTC value of any existing path. Done by modeling the flow on the path being
studied at its proposed new TTC level simultaneous with the flow on the existing path at
its TTC level while at the same time honoring the reliability criteria outlined in 2.2.1.
SWTC shall include the resolution of this adverse impact in its study report for the ATC
Path. (MOD-029-1a R2.5)
Where multiple ownership of Transmission rights exists on an ATC Path, allocate TTC of
that ATC Path in accordance with the contractual agreement made by the multiple owners
of that ATC Path. (MOD-029-1a R2.6)
Data Received for ATC Calculation (MOD-0001-1a R3.3)
•
Tucson Electric Power (TEP)
•
Salt River Project (SRP)
Data Provided for ATC Calculation (MOD-001-1a R3.4)
•
None
SWTC does not provide an allocation of transfer capability to any other entities. (MOD001-1a R3.5)
For ATC Paths whose path rating, adjusted for seasonal variance, was established, known
and used in operation since January 1, 1994, and no action has been taken to have the path
rated using a different method, set the TTC at that previously established amount. (MOD029-1a R2.7)
SWTC does not establish TTC for any ATC path where three phase faults damping is used
to determine stability limits. In Appendix C SWTC describes the process in developing
the TTC and ATC numbers on the SWTC system. A detailed documentation listing system
assumptions, base cases, contingencies and results are included. Also included in the report
are stability plots and a list of each path as either flow limited or reliability limited. Where
a path was deemed flow limited, NERC did not require entities to calculate the TTC rather
use the path thermal rating which is consistent with practices in the past. (MOD-029-1a
R2.8)
SWTC shall establish the TTC at the lesser of the value calculated in MOD-029-1a R2.2
or any System Operating Limit (SOL) for that ATC Path. (MOD-029-1a R3)
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Within seven calendar days of the finalization of the study report, SWTC (Transmission
Operator) shall make available to SWTC (Transmission Service Provider), the most current
value for TTC and the TTC study report documenting the assumptions used and steps taken
in determining the current value for TTC for that ATC Path. All SWTC paths may be
viewed on the SWTC OASIS (http://www.oatioasis.com/SWTC/index.html). (MOD-0291a R4)
The needs for updates are normally tied to a significant system modification such as a new
interconnected resource, transmission network modification and/or changes in forecast
loads.
7.
FIRM ATC CALCULATION METHODOLOGY
When calculating firm ATC for an ATC Path for a specified period, SWTC shall use the
following algorithm: (MOD-029-1a R7)
ATCF = TTC – ETCF – CBM – TRM + PostbacksF + counterflowsF
Where:
ATCF is the firm Available Transfer Capability for the ATC Path for that
period.
TTC is the Total Transfer Capability of the ATC Path for that period.
ETCF is the sum of existing reserved firm commitments for the ATC Path
during that period.
CBM is the Capacity Benefit Margin for the ATC Path during that period.
TRM is the Transmission Reliability Margin for the ATC Path during that
period.
PostbacksF are changes to firm Available Transfer Capability due to a
change in the use of Transmission Service for that period, as defined in
Business Practices
counterflowsF are adjustments to firm Available Transfer Capability as
determined by SWTC and specified in this ATCID.
8.
NON-FIRM ATC CALCULATION METHODOLOGY
When calculating non-firm ATC for an ATC Path for a specified period, SWTC shall use
the following algorithm: (MOD-029-1 R8)
ATCNF = TTC – ETCF – ETCNF – CBMS – TRMU + PostbacksNF + counterflowsNF
Where:
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ATCNF is the non-firm Available Transfer Capability for the ATC Path for
that period.
TTC is the Total Transfer Capability of the ATC Path for that period.
ETCF is the sum of existing reserved firm commitments for the ATC Path
during that period.
ETCNF is the sum of existing non-firm commitments for the ATC Path
during that period.
CBMS is the Capacity Benefit Margin for the ATC Path that has been
scheduled during that period.
TRMU is the Transmission Reliability Margin for the ATC Path that has
not been released for sale (unreleased) as non-firm capacity by the
Transmission Service Provider during that period.
PostbacksNF are changes to non-firm Available Transfer Capability due to
a change in the use of Transmission Service for that period, as defined in
Business Practices.
counterflowsNF are adjustments to non-firm Available Transfer Capability
as determined by SWTC and specified in this ATCID.
9.
IMPLEMENTATION
Transmission Model
When calculating TTCs for ATC Paths, SWTC shall use a Transmission model that
satisfies the following requirements: (MOD-029-1a R1) The model utilizes data and
assumptions consistent with the time period being studied and that meets the following
criteria: (MOD-029-1a R1.1)
Includes at least: The SWTC transmission area. Although equivalent representation of
radial lines and facilities 161kV or below is allowed, SWTC chose to represent all 115
kV and above excluding radial lines. All load off radial lines was lumped on the high
voltage (HV) side of the system it was located on. (MOD-029-1a R1.1.1)
All Transmission Operator areas contiguous to SWTC’s area. (Equivalent representation
is allowed) (MOD-029-1 R1.1.2)
Any other Transmission Operator area linked to SWTC’s area by joint operating
agreement. (Equivalent representation is allowed) MOD-029-1a R1.1.3
SWTC utilized a Western Electricity Coordinating Council (WECC) approved 2015 and
2016 Heavy Summer and Light Winter Operating cases. These cases are compiled by
WECC entities therefore they show the most up to data information known at the time of
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compilation. Therefore, SWTC modeled all system Elements as in-service for the assumed
initial conditions. (MOD-029-1a R1.1.2)
All WECC approved base cases include firm transfers required to meet projected load
levels in each case. Therefore, SWTC modeled all generation (may be either a single
generator or multiple generators) that is greater than 20 MVA at the point of
interconnection in the studied area. (MOD-029-1a R1.1.3)
SWTC does not maintain phase shifters, therefore this requirement does not apply. (MOD029-1a R1.1.4)
All WECC approved operating cases contain load forecast prepared by Sierra Southwest
Cooperative Services’ Inc. (Sierra) Power Services department in conjunction with
member cooperatives. Load forecast information is provided by SWTC’s Balancing
Authority, Western Area Power Administration, Desert Southwest (WALC) and to the
WECC for regional studies. (MOD-029-1a R1.1.5)
SWTC uses the most recent operating cases, each case was developed utilizing the best
information available at the time of the study for planned facility changes. In the event of
a change in the work plans or current configuration, the case was adjusted to reflect the
most relevant information. The following transmission facilities were adjusted to reflect
the cases.(MOD-029-1a R1.1.6)
SWTC delivers all AEPCO resources to the Class A Members in addition to its other
contractual obligations. Although three Class A Members can receive capacity and energy
from sources other than AEPCO, the total load for the members is modeled on the SWTC
Transmission System to ensure adequate delivery of all resources necessary to reliably
serve the entire forecasted Class A Member load as well as the loads associated with
SWTC’s transmission service agreements. SWTC did not currently have any Generation
Facility additions or retirements within the timeframe modeled. (MOD-029-1a R1.1.7)
SWTC incorporates Special Protection System (SPS) models where currently existing or
projected for implementation within the studied time horizon. SPS schemes that influence
the TTC results will be noted in the TTC study report for a specific ATC Path. SWTC
does not currently have any SPS’s in place. TEP and SWTC currently have a Local Area
Protection Scheme (LAPS) that is utilized under an outage on the TEP system, whereupon
SWTC will open a portion of its 115 kV system. Currently the LAPS is not defined under
NERC and WECC. (MOD-029-1a R1.1.8)
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Models series compensation for each line at the expected operating level, unless specified
otherwise below. (MOD-029-1a R1.1.9)
•
SWTC does not own or operate any series compensation devices on its
system.
Includes any other modeling requirements or criteria specified below. (MOD-029-1a
R1.1.10)
•
No additional modeling requirements or criteria were used in the model.
SWTC is listed as a Transmission Owner therefore they are responsible in maintaining
facility ratings based on the most limiting factors per the FAC 008-1 and 009-1 reliability
standards. (MOD-029-1a R1.2)
10.
ETC CALCULATION
When calculating ETC for firm Existing Transmission Commitments (ETCF) for a
specified period for an ATC Path, SWTC shall use the algorithm below: (MOD-029-1a
R5)
ETCF = NLF + NITSF + GFF + PTPF + RORF + OSF
Where:
NLF is the firm capacity set aside to serve peak Native Load forecast
commitments for the time period being calculated, to include losses, and
Native Load growth, not otherwise included in Transmission Reliability
Margin or Capacity Benefit Margin.
NITSF is the firm capacity reserved for Network Integration Transmission
Service serving Load, to include losses, and Load growth, not otherwise
included in Transmission Reliability Margin or Capacity Benefit Margin.
SWTC utilizes this calculation in the NL calculation.
GFF is the firm capacity set aside for grandfathered Transmission Service
and contracts for energy and/or Transmission Service, where executed
prior to the effective date of a Transmission Service Provider’s Open
Access Transmission Tariff or “safe harbor tariff.” SWTC does not
currently have any GF on its system.
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PTPF is the firm capacity reserved for confirmed Point-to-Point
Transmission Service. SWTC models these contracts using specified
megawatt quantity, point of receipt, and point of delivery.
RORF is the firm capacity reserved for Roll-over rights for contracts
granting Transmission Customers (TC) the right of first refusal to take or
continue to take Transmission Service when the TC’s Transmission
Service contract expires or is eligible for renewal. SWTC assumes that a
TC will rollover its existing long term TSR. To account for this,
transmission in the amount of the confirmed TSR is set aside. ROR is
modeled as using specified megawatt quantity, point of receipt and point
of delivery. If a TC does not exercise its rollover right, that amount may be
removed from the ETC, unless that capacity is reserved by another TC.
OSF is the firm capacity reserved for any other service(s), contract(s), or
agreement(s) not specified above using Firm Transmission Service as
specified in this ATCID.
When calculating ETC for non-firm Existing Transmission Commitments (ETCNF) for all
time horizons for an ATC Path SWTC shall use the following algorithm: (MOD-029-1a
R6)
ETCNF = NITSNF + GFNF + PTPNF + OSNF
Where:
NITSNF is the non-firm capacity set aside for Network Integration
Transmission Service serving Load (i.e., secondary service), to include
losses, and load growth not otherwise included in Transmission Reliability
Margin or Capacity Benefit Margin.
GFNF is the non-firm capacity set aside for grandfathered Transmission
Service and contracts for energy and/or Transmission Service, where
executed prior to the effective date of a Transmission Service Provider’s
Open Access Transmission Tariff or “safe harbor tariff.”
PTPNF is non-firm capacity reserved for confirmed Point-to-Point
Transmission Service.
OSNF is the non-firm capacity reserved for any other service(s),
contracts(s), or agreements(s) not specified above using non-firm
transmission service as specified in this ATCID.
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11.
COUNTERFLOW
SWTC accounts for internal counterflow by adding the appropriate Firm counter-schedules
to the Non-firm ATC for real time and next day periods (scheduling and operating
horizons). (MOD-001-1a R3.2.1)
Rationale: Counterflow from expected Firm Interchange schedules from reservations on
SWTC’s transmission system in the base case in the opposite direction is included at 100%
to Non-Firm ATC. Counterflow for the impact of firm schedules has been set to utilize the
“netting” of firm energy on paths to maximize the associated ATC. (MOD-0010-1a R3.2.2)
12.
GENERATION AND TRANSMISSION OUTAGE
Planned generation and transmission outages of the system are typically studied in advance
to assess the impact an outage may have on a specific path’s TTC for the expected
conditions during the outage. This provides quantification of the TTC impact and any
potential curtailment requirements. The effect of outages on the ATC calculation is
managed through WebTrans software. The percentage decrease in TTC on a path from an
outage is entered into WebTrans software which in turn triggers updates to the ATC
calculation. Outages are entered based on the known or scheduled start date and time
through the estimated restoration date and time. (MOD-001-1a R3.2)
Outages in Effect for Part of a Day
Outages in effect for part of a day will be determined from the starting date and time and
ending date and time. For an outage that is in effect part of a day, the hourly ATC will be
reduced by the indicated amount for any hours after the start time and any hours prior to
the end time. The daily ATC calculation will be set to the minimum hourly ATC. (MOD001-1a R3.6.1)
Outages in Effect for Part of a Month
Outages in effect for part of a month will be determined from the starting date and time
and ending date and time. The daily ATC for any days within the month will be set to the
minimum ATC for any hour for the day and the monthly ATC will be set to the minimum
daily ATC during the month. (MOD-001-1a R3.6.2)
Outages from other Transmission Providers not Mapped to the SWTC Transmission
System
All transmission studies are performed as off-line studies with sufficient detail to assess
impacts of outages from other Transmission Service Providers within the model. Outages
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of one Transmission Provider with known impacts on another Transmission Provider or
Transmission Operator are communicated sufficiently in advance to allow time for off-line
studies to assess TTC and update ATC postings.(MOD-029-1a R3.6.3)
13.
DETERMINATION OF CBM AND TRM
SWTC does not use CBM on any ATC paths therefore; SWTC’s CBM value is set to
zero (0).
SWTC does not use TRM on any ATC paths therefore; SWTC’s TRM value is set to zero
(0).
SWTC’s CBMID and TRMID are posted on SWTC’s OASIS
http://www.oatioasis.com/SWTC/
14.
POSTBACKS
Postbacks are positive adjustments to ATC due to reservation annulments, redirects,
recalls, or the release of unscheduled use of confirmed reserved firm capacity.
SWTC applies Postbacks based upon the following criteria:
•
•
•
•
15.
Recall of transmission reservation
Redirect of a transmission service on a firm basis
Annulment of a transmission reservation
Released capacity due to unscheduled firm transmission reservations
(Scheduling and Operating Horizons only)
DATA RETENTION
SWTC shall keep data or evidence to show compliance for a specific audit period unless
directed by WECC to retain specific evidence for a longer period of time as part of an
investigation:
16.
REQUESTS FOR DATA
SWTC, as the Transmission Provider, shall make this ATCID available to all entities by
posting it on the SWTC OASIS. (MOD-001-1a R5)
SWTC will respond to requests for ATC data within thirty (30) days of receiving such
request. (MOD-001-1a R9) Such request shall be made to the following:
Director of System Operations
Shane Sanders
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ssanders@swtransco.coop
520-586-5239
Data that may be provided is listed in Appendix E.
17.
VERSION HISTORY
Version
0
Date
3-31-2011
Change Tracking
E.King
12-13-2011
Action
Creation & Implementation of
documentation
Administrative cleanup
1
2
12-31-2012
Language cleanup & updated Study
Tumarin/Sanders
3
12-31-2013
Annual Update
Tumarin/Sanders
4
06-30-2014
Annual Update
Tumarin/Sanders
5
07-07-2015
Annual Update
Tumarin/Sanders
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Available Transfer Capability Implementation Document
Version 3
Appendix A
SWTC Rated Path Numbers
SWTC – MOD-29 Results Table
SWTC Path
Limiting Element/Limiting Contingency
TTC
(MW)
Apache 115 kV – Hayden 115 kV
Flow Limited
114
Hayden 115 kV – Apache 115 kV
Flow Limited
114
Apache 230 kV – Bicknell 230 kV
Flow Limited
309
Bicknell 230 kV – Apache 230 kV
Flow Limited
309
Apache 230 kV – Dos Condados 230 kV
Flow Limited
402
Dos Condados 230 kV – Apache 230 kV
Flow Limited
402
Apache 230 kV – Winchester 345 kV
Flow Limited
402
Winchester 345 kV – Apache 230 kV
Flow Limited
402
Vail 345 kV – Bicknell 230 kV
Flow Limited
225
Bicknell 230 kV – Vail 345 kV
Flow Limited
225
Hackberry 230 kV – Dos Condados 230
kV
Dos Condados 230 kV – Hackberry 230
kV
Marana 115 kV – Bicknell 230 kV
Flow Limited
402
Flow Limited
402
Flow Limited
119
Bicknell 230 kV – Marana 115 kV
Flow Limited
64
Greenlee 345 kV – Morenci 230 kV
Flow Limited
193
Morenci 230 kV – Greenlee 345 kV
Flow Limited
193
Morenci 230 kV – Hackberry 230 kV
Flow Limited
402
Hackberry 230 kV – Morenci 230 kV
Flow Limited
402
Apache 230 kV – Apache 115 kV
Flow Limited
224
Apache 115 kV – Apache 230 kV
Flow Limited
224
Palo Verde 500 kV Pinal West 345 kV
(SRP Owner)
Refer to SRP Path Rating Methodology
(SRP Contractually limited SWTC 7.3%)
120
West Wing 345 kV - Pinal West 345 kV
(TEP Owner)
Refer to TEP Path Rating Methodology
(TEP Contractually limited SWTC 24%)
161
Pinal West 345 kV - Vail 345 kV
(TEP Owner)
Refer to TEP Path Rating Methodology
(TEP Contractually limited SWTC 24%)
222
The Three Points to Bicknell segment of the Marana – Bicknell 115 kV line is
limited to 64 MW due to conductor rating. It is determined that due to loads
dropped off prior to the limited segment of this line, the rating of the Marana –
Bicknell 115 kV line will be 92 MW.
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Appendix B
Rated Path Methodology
(Available Upon Request)
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Appendix C
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Appendix D
ATC DATA TO BE PROVIDED UPON REQUEST
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Expected generation and Transmission outages, additions, and retirements.
Load forecasts.
Unit commitments and order of dispatch, to include all designated network resources and
other resources that are committed or have the legal obligation to run, as they are
expected to run, in one of the following formats chosen by the data provider.
Dispatch Order
Participation Factors
Block Dispatch
Aggregated firm capacity set-aside for Network Integration Transmission Service and
aggregated non-firm capacity set aside for Network Integration Transmission Service (i.e.
Secondary Service).
Firm and non-firm Transmission reservations.
Aggregated capacity set-aside for Grandfathered obligations
Firm roll-over rights.
Any firm and non-firm adjustments applied by the Transmission Service Provider to
reflect parallel path impacts.
Power flow models and underlying assumptions.
Contingencies, provided in one or more of the following formats:
o A list of Elements
o A list of Flowgates
o A set of selection criteria that can be applied to the Transmission model used by
the Transmission Operator and/or Transmission Service Provider
Facility Ratings.
Any other services that impact Existing Transmission Commitments (ETCs).
Values of Capacity Benefit Margin (CBM) and Transmission Reliability Margin (TRM)
for all ATC Paths or Flowgates.
Values of Total Flowgate Capability (TFC) and AFC for any Flowgates considered by
the Transmission Service Provider receiving the request when selling Transmission
service.
Values of TTC and ATC for all ATC Paths for those Transmission Service Providers
receiving the request that do not consider Flowgates when selling Transmission Service.
Source and sink identification and mapping to the model.
20