Exhibit 99.219
TRANSMISSION CONGESTION MANAGEMENT
IN THE EMERGING ENERGY MARKETS
DARIUSH SHIRMOHAMMADI PAUL GRIBIK ALI VOJDANI
[PEROT SYSTEMS LOGO]
Presentation by:
DARIUSH SHIRMOHAMMADI
1998 SEPOPE CONFERENCE
SALVADOR, BRAZIL
MAY 1998
1
OBJECTIVE
"Cover all facets of transmission congestion management from the entities
responsible for managing congestion on transmission system to the protocols and
analytical tools and methods needed to perform congestion management"
2
OUTLINE
- - Background
- - Energy Market Structures
- - Independent System Operator (ISO)
- - Transmission Congestion Management
- - Analytical tools and methodology for congestion management
- - Congestion Management in California
3
BACKGROUND
- - Fundamental restructuring of the electric utility industry commonplace
in many parts of the world
- The drivers for and the structure of emerging markets not the
same everywhere
- - One fact applies to all emerging energy markets: transmission and
generation services will be unbundled from one another
- Generation market will become fully competitive with many market
participant
- Operation of transmission system will remain regulated with the
main goal of allowing "open, non-discriminatory and comparable"
access
- Retail side will see the slowest evolution: largely regulated for
the near future but fully deregulated and competitive in the long
run
4
INDEPENDENT SYSTEM OPERATOR
- - Transmission system will remain the central element of the energy
production and delivery systems
- - Operation of the transmission system is expected to be entrusted to an
independent entity with no direct functional ties to energy suppliers:
Independent System Operator (ISO)
- System operations department of a single utility which has been
functionally separated from the generation function - possible
- "Super control area operator" responsible for operating the power
systems of several interconnected electric utilities - probable
5
ENERGY MARKET STRUCTURES
- - Many emerging market structures are possible based on assignment of
tasks to the entities in the emerging markets
- - Only two broad forms of market structures will have direct impact of
transmission congestion management
- Pool market structure
- Bilateral Contracts market structure
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POOL MARKET STRUCTURE
[FLOWCHART]
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POOL MARKET STRUCTURE
- - ISO is responsible for power market administration and system operations
- - Congestion management is integral part of energy auction performed by
the ISO
- ISO will create trade among market participants
- ISO may leave bilateral contract schedules alone -- treat them as
"price-takers" (e.g., PJM)
8
BILATERAL CONTRACTS MARKET STRUCTURE
[FLOWCHART]
9
BILATERAL CONTRACTS MARKET STRUCTURE
- - Market administration (energy auction) is performed by an entity
separate from the ISO
- - ISO exercises congestion management only if necessary -- collective
schedules submitted by market participants violates constraints
- ISO includes all market participants in transmission congestion
relief
- ISO will not force trade between market participants -- market
separation constraints (e.g., California)
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ISO ROLES AND RESPONSIBILITIES
- - Long-range planning services -- few ISOs
- - Power market administration services -- many ISOs
- - Forward market operation services -- most ISOs
- Involves transmission congestion management
- - Real-time system operations services -- all ISOs
- Involves transmission congestion management
- - Metering, settlement and billing services -- most ISOs
- - Open information communication services -- all ISOs
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FORWARD MARKET OPERATION
[FLOWCHART]
12
REAL-TIME SYSTEM OPERATIONS
[FLOWCHART]
13
SYSTEM SCHEDULING FUNCTION
[FLOWCHART]
14
SYSTEM DISPATCH FUNCTION
[FLOWCHART]
15
SYSTEM DISPATCH MODEL
- - Responsible for transmission congestion management
- Provide comparable transmission service to all energy market
participants
- Ration the use of scarce transmission resources among
transmission users according to the "value" placed on them by
market participants
- Value established by schedule adjustment bids
- Price use of transmission resources to send correct economic
signals
- Market Separation Protocol: When rationing transmission capacity
do not perform trade among different Bilateral Transactions --
for Bilateral Contracts Market
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SYSTEM DISPATCH MODEL
- - Main analytical tool is an OPF with the following Specifications:
- Objective: minimize the cost of system operation
- Controls: all dispatchable active/reactive resources and trades,
transmission controls
- Constraints: static network operating constraints, constraints on
individual control variables, inter-temporal constraints, power
flow constraints
- Local controls
- Market Separation Constraint (if applicable): match supply and
demand values for individual SCs
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TRANSMISSION CONGESTION MANAGEMENT IN CALIFORNIA
- - Two forms of congestion management
- Interzonal transmission congestion management
- Intrazonal transmission congestion management
- - Performed for both forward energy markets and real-time market
- Day-ahead market -- Interzonal and Intrazonal
- Hour-ahead market - Interzonal and Intrazonal
- Real-time -- Intrazonal only
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INTERZONAL CONGESTION MANAGEMENT
- - Divide ISO controlled grid and neighboring areas into congestion zones
-- 24 at this time
- Within a zone transmission congestion will infrequent low cost to
relieve
- Between zones transmission congestion will be frequent and high
cost to relieve
- Transmission constraints between zones limited to real power
flows across zonal interfaces
- Zones may be changed on regular basis
- - DC OPF used to manage congestion
- Ration transmission based on value claimed by scheduling
coordinators -- via adjustment bids
- Calculate congestion prices based on value claimed by scheduling
coordinators -- via adjustment bids
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INTERZONAL CONGESTION MANAGEMENT
[DIAGRAM]
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INTRAZONAL CONGESTION MANAGEMENT
- - Relieve congestion within each of the congestion zones for all system
operating constraints
- MW flow limits
- MVA flow limits
- Amperage limits
- Voltage limits
- - ISO adjusts the schedules of all SCs as little as possible without
regard to market separation constraints to relieve congestion
- May force trade between SCs
- Costs addressed via uplift charges allocated to all demands
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CONGESTION MANAGEMENT IN DAY-AHEAD MARKETS
[DIAGRAM]
22
EXAMPLE OF INTERZONAL CONGESTION MANAGEMENT
- - System schedules before congestion management
[DIAGRAM]
23
EXAMPLE OF INTERZONAL CONGESTION MANAGEMENT
- - System schedules after congestion management
[DIAGRAM]
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CONCLUSIONS
- - Transmission congestion management is one of the most important and
complex elements of managing and operating emerging energy markets
- - We described the principal factors involved in managing transmission
congestion
- Entities responsible for managing transmission congestion and
their related roles and responsibilities
- Systems and analytical tools that are used for congestion
management
- Ration scarce transmission resources
- Price congested transmission paths
- - OPF will be the main tool used for congestion management
- Many variations will be actually implemented in the market
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