Transcript Presentation: Generation and Import Deliverability

Generation and Import
Deliverability Baseline Study
CAISO Stakeholder Meeting
May 9, 2005
Today’s Agenda
•
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Background and meeting objectives
Review of study methodology, assumptions and
identified issues
Lunch (on your own)
Review of study results
Review of conclusions/recommendations
Discussion of next steps
Status of locational capacity analysis
2
Meeting Objectives
• Describe preliminary results and implications
• Describe ISO recommendations for deliverability
in this Baseline Study
• Receive stakeholder input on this Preliminary
Baseline Study
3
The Concept of Deliverability
• Deliverability, for resource adequacy purposes,
ensures the output of a generating unit can reach
load under peak conditions
• Deliverability is an essential element of the
CPUC’s resource adequacy requirement
• Deliverability does NOT ensure dispatch:
– Deliverability does not mean 100% congestion
elimination for all load levels
4
The Concept of Deliverability
(continued)
• Resources considered in deliverability include:
– Existing generators (for aggregate of load)
– Imports
– Generators within transmission-constrained
areas
– New generation interconnections
5
Deliverability Strawperson
• The ISO’s proposed strawperson deliverability proposal
consists of three assessments:
– Deliverability of Generation to the aggregate of load
– Deliverability of Imports
– Deliverability to Load within transmission constrained
areas (locational capacity requirement)
• The Baseline study and this presentation focus on the
deliverability of generation and imports only
6
Overview
- How We Got to this Point • Spring 2004 - ISO proposes a straw person deliverability
methodology to CPUC
• Late 2004 - CPUC approves methodology in principle
• January 2005 - ISO begins baseline study
• January and February 2005 – PTOs provide data to ISO
• May 2005 – ISO publishes preliminary results of baseline
7
study
Overview
(continued)
- The Bottom Line • This preliminary study confirms that:
– historical summer peak imports levels are deliverable.
– most of the existing generating units in the ISO Control Area
are deliverable
• Some transmission upgrades are needed over the next
few years to make all existing generating units fully
deliverable to load using this methodology
• The ISO intends to recommend that all existing
generators be considered deliverable, and the ISO will
work with the PTOs to identify and implement the
necessary transmission upgrades
8
Overview
(continued)
Further Steps for Baseline Study
• May, 2005 - ISO receives stakeholder input and conducts
further stakeholder meetings/conference calls if necessary
• June, 2005 - ISO completes deliverability analysis,
including any adjustments to the methodology determined
to be necessary during stakeholder review
• Early July, 2005 - ISO publishes final results of Baseline
Deliverability Study
9
Preliminary Baseline Study for
Generation and Imports
Study Assumptions and
Identified Issues
• Part I:
Background and Study Methodology
• Part II:
Study Assumptions
• Part III:
Identified Study Issues
11
Deliverability of Generation:
Assumptions
• Capacity resources within a given sub-area must
be able to be exported to other parts of the Control
Area experiencing a resource shortage due to
forced generation outages
12
Transmission Lines
in California
13
Power Plants in
California
14
Reserve Shortage in
California
* Summer Peak Load
* Power Plants Forced out
*** SCENARIO 1***
15
Reserve Shortage in
California
* Summer Peak Load
* Power Plants Forced out
*** SCENARIO 1***
All generation in
Pocket 1 available
16
Reserve Shortage in
California
* Summer Peak Load
* Power Plants Forced out
*** SCENARIO 2***
All generation in
Pocket 1 available
Forced outages are
random and occur
throughout the
system
17
Generation Pocket Analysis
• The location of units forced out and causing reserve
margin shortage in Scenarios 1 and 2 do not significantly
change the loadings on constrained transmission lines
associated with the generation pocket
• The units forced out in Scenarios 1 and 2 are outside of the
generation pocket study area, so their status and dispatch
levels, in aggregate, do not significantly impact the study
area
• The hundreds of thousands of generation forced outage
scenarios can be sufficiently represented by evenly
distributing the forced outages across the system
18
Deliverability of Generation: Methodology
• A deliverability assessment should be applied to
existing and planned generation located in the control
area
– This baseline study covers planned generation through 2006
• Developed from PJM Methodology
• Peak load conditions
• Aggregate of generation can be transferred to aggregate
of the ISO Control Area Load
19
Generation Deliverability
Baseline Analysis
• First we need to apply deliverability test to existing
system:
– Validate deliverability test methodology and parameters
– Identify all overloads
– Mitigate overloads
• Once all overloads in baseline analysis are
mitigated, then new overloads that are identified
(using the same test) can be consistently and
equitably assigned to proposed new generation
projects
20
Overloads identified during the baseline
study could be mitigated by:
– Building new or upgrading existing transmission
facilities
– Implementing operating solutions (i.e. short term
ratings, RAS/SPS)
– Limit capacity to be counted from the portion of
existing generation that is deliverable
21
Overview of Test Procedure
1. Build power flow base case model
•
Create base case generation dispatch
2. Create study areas around each line and
transformer and analyze them individually
3. Identify overloaded lines and transformers
constraining generation capacity and the units
that are constrained
22
Elaborating on the Base Case Dispatch
• Dispatching generation in the base case essentially means
that we evenly distribute the available generation
– Since all available capacity is needed, it is all dispatched without
consideration of cost
• Base case values will also represent approximate dispatch
of generation outside of the study areas during the analysis.
• Generation inside of the study areas will be maximized
during the study
23
Study Areas Are Created Around
Each Line and Transformer
• Each transmission line and transformer is analyzed
individually
• A study area is established for each line and transformer that
includes all generation with a 5% distribution factor or
greater on the particular line or transformer
• Capacity generation dispatch inside the study area is
maximized to determine the maximum potential loading on
the line or transformer.
• Generation outside the study area is proportionally decreased
to balance the load and resources
• This process is intended to test the ability of resources inside
of the study area to be dispatched at full output when various
resources outside of the study area are unavailable
24
Los Banos
230 kV
Bellota
230 kV
-16%
Dos Amigos
230 kV
Moss Landing
230 kV
Example Generation
Deliverability Test
Study Area for GreggBorden 230 kV line
Melones
230 kV
Warnerville
230 kV
1.6%
Wilson
230 kV
Coburn
230 kV
Panoche
230 kV
8.5%
23%
Storey
230 kV
Helms
230 kV
230/115 kV
Bank #1
8.8%
Henrietta
230 kV
Gates
230 kV
Morro Bay PP
230 kV
10%
Mc Call
230 kV
Borden
230 kV
Line
overload
Gregg
230 kV
Arco
230 kV
Gates
500 kV
Midway
230 kV
2%
DFAX%
25
Line
outage
Generation Deliverability Summary
• Baseline analysis identifies all cases where thermal
overloads occur with the existing set of facilities
• The same test applied in this baseline analysis will be
applied with new generation capacity so all new
overloads can be consistently and equitably assigned to
proposed new generation projects
26
Deliverability of Imports -Assumptions
• California is dependent on imports to satisfy its resource
requirements
• Imported resources in the resource plans of all LSEs need to be
assessed by the ISO to ensure that they can be simultaneously
accommodated on the transmission grid
• When relying on imports to meet reserve margin requirements,
LSEs with the assistance of the ISO should demonstrate that
their imports are deliverable from the tie point to aggregate load
on the ISO System using a deliverability test procedure similar
to the generation deliverability test
27
Deliverability of Imports
and Internal Generation –
Assumptions
• Assessing the deliverability of imports and generation
simultaneously will ensure that any interaction between the
deliverability of imports and generation is considered
• This can be done by modeling import capacity to be used
for resource adequacy planning purposes as the starting
point for import assumptions in the internal generation
deliverability analysis
• The initial import capacity would be based on historical
data during summer peak load and high import conditions.
• Deliverability conflicts between imports and internal
generation were expected to be minimal using historical
28
import data
Deliverability of Imports
and Internal Generation –
Summary
• The initial baseline analysis would determine the
deliverability of all existing internal generation units and
the total amount of imports on a path by path basis
• This preliminary analysis did not identify any
deliverability impacts associated with the historical import
levels
• Total deliverable import capacity would be allocated to
LSEs using a predetermined allocation methodology (to be
determined by the CPUC)
29
Network model and
Generation Capacity Study –
Assumptions
• A network model of the ISO Controlled Grid modeling the year 2006
was used for this study
• Generation Capacity data collected from generation owners was used
for this study
– Capacity values as defined in the Resource Adequacy Workshop
Report:
• Net Dependable Capacity
• Qualified Capacity
– Capacity values under Summer Peak temperature conditions.
– All units commercially operable by summer 2006 were modeled
30
Import, Load and Contingency Study
-- Assumptions
• Imports modeled in the base case are based on
OASIS import schedule data from 2003 and 2004:
– Summer peak load, maximum import
conditions
– by branch group
– The 2006, 1 in 5 peak load forecast for the ISO Control
Area was modeled in the base case
• All NERC Category B and C contingencies were
analyzed while applying the study methodology:
– excluding C.3 overlapping contingencies
31
Identified Generation Data Issues
1.
For some units, conflicting capacity data was provided by
the generation owner and the generation power
purchasing utility, due to their different interpretations of
the Qualifying Capacity definitions in the CPUC’s
Resource Adequacy Workshop Report
• The highest capacity value was tested in the base case.
2.
Capacity data provided for some units was significantly
higher than the capacity data in WECC basecases
• The highest capacity value was tested in the base case
32
Identified Generation Data Issues
3.
For intermittent generation, Qualifying Capacity data represents an
average production over summer peak load hours
•
In some cases this average capacity value could be deliverable
but production amounts above that average are not deliverable
•
In this situation the average capacity amount is not a valid
qualified capacity value since it could represent levels of
production that would not be deliverable based on the
deliverability methodology
•
For this study, the capacity data already in the original WECC
base case was assumed to be the maximum production during
summer peak load hours to ensure that all production values
represented by the average capacity would be deliverable
33
Identified Line Rating Issues
• Some ratings have recently been entered into the ISO
Transmission Register that are lower than the previously
provided facility rating
• These new ratings have not been evaluated using
traditional transmission assessment methodologies
• Therefore identified deliverability issues associated with
facilities that have this type of rating issue should not be
attributed to the proposed deliverability methodology
34
Preliminary Baseline Study for
Generation and Imports
Study Methodology
and
Results
Deliverability Problems
• A deliverability problem is identified by conditions when
resources cannot be delivered to load because their outputs
cause reliability problems in the transmission system
• Causes of deliverability problems:
- Dispatch of resources: Under normal conditions, deliverability
problems may occur from the dispatch of resources
- Dispatch of resources and contingencies: Combined impact from
these two factors cause deliverability problems under emergency
conditions
• This study looks for potential deliverability problems from a
combination of dispatch and contingency scenarios
36
Study Methodology
• The study technique is divided into two main parts:
1) Screening process and 2) Verification process
• Screening process searches for potential deliverability
problems using linear analysis technique. The main purpose
of this process is to minimize the number of scenarios that
will be analyzed by verification process
• Then the scenarios that pass the screening process will be
analyzed by Verification process to confirm deliverability
problems using AC power flow
37
Overview of Study Methodology
All possible scenarios
Screening
Process
Scenarios with potential
problems
AC Verification
Process
Scenarios with
deliverability
problems
38
Study Methodology –
Screening Process
• Identify potential deliverability problems using linear analysis
• Since it does not require power flow solution for all scenarios
This technique speeds up the study process significantly
• Scenarios that are identified by the screening process will be
analyzed again with the verification process
39
Study Methodology –
Verification Process
• Simulates the scenarios identified by the screening process
by utilizing a simplified governor power flow
• If a deliverability problem is confirmed, calculate
generation capacity reduction that will lower power flow
on the overloaded facility below its rating
40
Output Report - Example
Monitored Facility
Details of the
outage
Resources with DFAX
5% or higher
41
Output Report - Example
42
Output Report - Example
39%
-3%
26%
24%
21%
43
DFAX
Output Report
The Output Report assigns deliverability status of each facility into
one of the following categories:
• Fully deliverable: 100% capacity of the resources using this
transmission facility could be counted as deliverable for resource
adequacy purposes
• Partially deliverable: Without mitigation, a fraction of capacity
should be discounted due to deliverability problems
• Non-deliverable: This is an extreme case where the resources
substantially contribute to deliverability problems. Without
mitigation, no part of the resources utilizing this facility can be
counted for resource adequacy purposes under this test
44
Study Results –
Summary of preliminary deliverability problems
PG&E Service Territory
HUMBOLDT
No
Limiting Facility
PCT
Overload
1
2
Humboldt Bay-Humboldt 60 kV line #1
Eureka - Humboldt Bay 60 kV line #1
108.91
101.91
Contingency
Humboldt Bay-Humboldt 60 kV line #2
Humboldt Bay-Humboldt 115 kV line #1
Type
Curtailment
(MW)
C
7.51
2.19
Total Curtailment
7.51
SIERRA
No
Limiting Facility
PCT
Overload
Contingency
Type
Curtailment
(MW)
1
Palermo - Colgate 60 kV line #1
152.98
Palermo-Colgate 230 kV line #1
Colgate-Rio Oso 230 kV line #1
Colgate PP #1 and #2
C
Insufficient*
2
3
4
Chicago Park - Higgins 115 kV #1
Higgins - Bell 115 kV line #1
Drum - Dutch Flat 115 kV #1
117.79
100.27
117.13
Rio Oso-Atlantic 230 kV line #1
Rio Oso-Goldhill 230 kV line #1
C
89.16
1.37
75.39
5
Drum - Dutch Flat 115 kV #1
101.8
C
7.91
6
East Nicholas - Rio Oso 115 kV line #1
108.1
C
109.45
Atlantic-Goldhill 230 kV line #1
Rio Oso-Goldhill 230 kV line #1
Colgate-Rio Oso 230 kV line #1
Table Mt - Rio Oso 230 kV line #1
Colgate PP #1
Total Curtailment
45
*Curtailing the generators alone is not sufficient to mitigate the overloading conditions
210.06
Study Results
PG&E (cont)
KERN
No
1
Limiting Facility
Taft 115/70 kV Bank #2
PCT
Overload
103.21
Contingency
Midway-Taft 115 kV line #1 and
Fellows-Taft 115 kV line #1
Type
Curtailment
(MW)
C
2.19
Total Curtailment
2.19
FRESNO
No
Limiting Facility
PCT
Overload
1
2
Gregg - Figarden Tap2 230 kV line #1
Figarden Tap2 - Ashlan 230 kV line #1
154.63
143.11
Contingency
Gregg-Herndon 230 kV line #1 and #2
Type
Curtailment
(MW)
C
716.02
565.11
Total Curtailment
716.04
LOS PADRES
No
1
Limiting Facility
Morro Bay 230/115 kV Bank #6
PCT
Overload
154.63
Contingency
Morro Bay-Mesa 230 kV line #1 and
Morro Bay-Diablo 230 kV line #1
Type
Curtailment
(MW)
C
Insufficient*
Type
Curtailment
(MW)
C
Insufficient*
Total Curtailment
DIABLO
No
1
Limiting Facility
Pittsburg-Clayton 115 kV line #1
PCT
Overload
126.97
Contingency
Pittsburg-Clayton 115 kV line #3 and #4
Total Curtailment
46
*Curtailing the generators alone is not sufficient to mitigate the overloading conditions
Study Results
SCE Service Territory
Western LA Basin
Estimated Gen Reduction to alleviate overloads =
1100
Limiting Facility
From Name
ALMITOSE
To Name
kV
CENTER S 230
MW
Contingency
ckt
1
ALMITOSE
BARRE
230
1
HINSON
LITEHIPE
230
1
LA FRESA
REDONDO 230
2
LA FRESA
REDONDO 230
1
PCT
From Name
Overload
ALMITOSE
117
ALMITOSW
ALMITOSE
103
ALMITOSW
LA FRESA
119
LA FRESA
LA FRESA
124
LITEHIPE
LA FRESA
124
LITEHIPE
47
To Name
kV
BARRE
LITEHIPE
CENTER S
LITEHIPE
REDONDO
REDONDO
REDONDO
REDONDO
REDONDO
REDONDO
230
230
230
230
230
230
230
230
230
230
ckt Type
1
1
1
1
1
2
1
1
2
1
C
C
C
C
C
Study Results
SCE (Cont)
East of Kramer 115 kV System
Estimated Gen Reduction to alleviate overloads =
Limiting Facility
PCT
From Name To Name kV ckt
From Name
Overload
VICTOR
TAP601
ELDORDO MTN PASS 115 1
115
VICTOR
ROADWAY
20 MW
Contingency
To Name
KRAMER
KRAMER
TAP601
TAP601
kV
ckt Type
115
115
115
115
1
1
1
1
C
Tehachapi
Estimated Gen Reduction to alleviate overloads =
65 MW
Limiting Facility
Contingency
PCT
From Name To Name kV ckt
From Name To Name
kV
Overload
GOLDTOWN TAP 74
66 1
ANTELOPE CALCMENT 66
LANCSTR
GOLDTOWN 66 1
48
ckt Type
1
B
Study Results
SCE (Cont)
North of Lugo
Estimated Gen Reduction to alleviate overloads =
Limiting Facility
PCT
From Name To Name kV ckt
From Name
Overload
LUGO
VICTOR
230 2
104
LUGO
LUGO
VICTOR
230 1
104
LUGO
LUGO
LUGO
LUGO
VICTOR
230 1
106
KRAMER
KRAMER
49
85 MW
Contingency
To Name
kV
VICTOR
VICTOR
KRAMER
KRAMER
LUZ LSP
BLM WEST
230
230
230
230
230
230
ckt Type
1
2
1
2
1
1
B
B
C
Study Results
SDG&E Service Territory
Encina-Escondido 138 kV System
Estimated Gen Reduction to alleviate overloads =
Limiting Facility
From Name
To Name
kV ckt
PCT
From Name
Overload
CALAVRTP
CANNON
138
1
103
CALAVRTP
SHADOWR
138
1
106
CALAVRTP
CANNON
138
1
108
CALAVRTP
SHADOWR
138
1
104
SANLUSRY
SANLUSRY
CRSTNTS
JAP MESA
TALEGA
ESCNDIDO
ENCINATP
ENCINATP
ENCINATP
NORTHCTY
BATIQTOS
BATIQTP
BATIQTP
50
50
MW
Contingency
To Name
kV
SANLUSRY
SANLUSRY
TALEGATP
TALEGATP
TALEGATP
EPP
ENCINA
SANLUSRY
ESCNDIDO
PENSQTOS
BATIQTP
PENSQTOS
ENCINA
230
230
69
69
69
230
230
230
230
138
138
138
138
ckt Type
1
2
1
1
1
1
1
1
1
1
1
1
1
C
C
C
C
Study Results
SDG&E (Cont)
South Bay/Border 69 kV System
Estimated Gen Reduction to alleviate overloads =
Limiting Facility
PCT
From Name
To Name
kV ckt
From Name
Overload
JAMACHA
CHOLLAS
SPRNGVLY
69 1
101
JAMACHA
MONTGMRY
SOUTHBAY SWEETWTR 69 1
126
OTAY
MONTGYTP
51
110
MW
Contingency
To Name
kV
MIGUEL
MIGUEL
SOUTHBAY
SOUTHBAY
SOUTHBAY
69
69
69
69
69
ckt Type
1
2
1
2
1
C
C
Study Results
Summary of the Deliverability Problems
For the Entire System
Number of overloaded
facilities
Number of contingencies
causing the overloads
Total MW Curtailment
PG&E
SCE
SDG&E
Total
12
11
4
27
9
11
6
26
10*
170**
160
340
*Note 1: 923 MW of deliverability problems in the PG&E area are related to
criteria violations identified in the transmission expansion planning process.
**Note 2: 1100 MW of deliverability problems in the SCE area are related to
recent transmission line deratings. The revised line ratings will be reflected in
SCE’s 2005 grid planning assessment. Any
52 identified criteria violations will be
addressed as part of that process.
QUESTIONS?
53
Preliminary Baseline Study for
Generation and Imports
Study Conclusions and
Recommendations
***Stakeholder Comments Needed for these Recommendations
Recommendation:
Approve the Deliverability Study Methodology
for generation interconnection study purposes
and for resource adequacy counting purposes
• No fatal flaws in the Deliverability Study Methodology
were identified
• The majority of issues identified by this study are not
attributable to the application of the proposed
Deliverability Study Methodology
• This study, using the proposed methodology, demonstrates
that historical summer peak imports and almost all of the
existing generation are deliverable
55
Recommendation:
Identified issues should be investigated further by
PTOs
• The issues identified by this study should be
investigated and resolved by the PTOs
• Alternatives for resolution include:
– Building new or upgrading existing transmission
facilities
– Implementing operating solutions (i.e. short term
ratings, RAS/SPS)
56
Recommendation:
Existing units and imports should be considered
deliverable
• During an interim period, including but not limited
to the study year 2006, all generation should be
considered to be fully deliverable
• By a date to be determined, any deliverability
issues from this baseline study that affect existing
units and imports should be resolved by the PTOs
57
Recommendation:
ISO with PTO support should perform additional
baseline study
• A Phase II baseline study needs to be performed by the
ISO with PTO support to include all new generation
projects that have approved interconnection studies and
operating dates after 2006 to establish the Deliverability of
these projects
• The ISO should review with stakeholders a planned
schedule for performing this additional baseline study
58
Next Steps
Proposed Action for Finalizing
Phase I Baseline Study
• May 23, 2005 - ISO receives written stakeholder
comments
• Early June – ISO conducts further stakeholder
meetings/conference calls if necessary
• June, 2005 - ISO completes deliverability analysis,
including any adjustments to the methodology determined
to be necessary during stakeholder review. ISO publishes
final results of Phase I Baseline Deliverability Study
• Early July, 2005 - Begin Phase II Baseline Deliverability
Study
59
Status of Locational Capacity
Analysis
• ISO presented Locational Capacity Requirement methodology/criteria
at CPUC workshops late 2004
• Three on-going processes are inter-related
– Resource adequacy
– Deliverability
– Locational capacity requirement
• Present plans are that a transition from RMR to Local Capacity will
need to occur in 2006
– ISO RMR analysis currently underway with results presented in May 2005
– ISO will re-study the system utilizing the proposed Locational Capacity
methodology/criteria with results presented in June 2005
• ISO is working towards all three processes coming together in July
2005
60