Presentation talks about what is congestion management and how it can be removed.

1. LOGO Company name
CONGESTION
MANAGEMENT
Presented By:
GAURAV KUMAR

2.  Congestion Management
 Limits: Transfer Capability
 Effects: Congestion
 Features: Schemes/Methods
 Classification: Methods
 Congestion process
 Methods: Congestion
 Comparison
 Conclusion
CONTENT

3. CONGESTION MANAGEMENT
 Whenever the physical or operational
constraints in a transmission network become
active, the system is said to be in a state of
congestion.
 Congestion management is a mechanism to
prioritize the transactions and commit to such
a schedule which would not overload the
network.
 As an electrical energy can’t be stored in
large chunks, it is done on the real time basis.

4. CONGESTION MANAGEMENT
Congestion management involves precautionary
as well as remedial action on system operator’s
part, as follows:-
 Allow only that set of transactions which,
taken together, keeps the transmission
system within limits.
 Even if this care is taken, in real time, the
transmission corridors may get overloaded
due to unscheduled flows. The system
operator has to take some remedial action.

5. Congestion is said to have occurred when
system operator finds that all the transactions
cannot be allowed on account of overload on
the transmission network. So it helps to:-
Minimized interference of the transmission
network in the market for electric energy
Secure operation of the power system
Improvement of market efficiency
Manage power flow with existing
Transmission line
OBJECTIVE

6. LIMITS: TRANSFER CAPABILITY
 Congestion, as used in deregulation parlance,
generally refers to a transmission line hitting
its limit.
1. Thermal Limits
2. Voltage Limits
3. Stability Limits
 ANALYSIS:
For a short line, the line loading limit is
dominated by its thermal limit and for a long
line, stability limit is the main concern.

7. Market Inefficiency:
In the short term, market
efficiency refers to a
market outcome that
maximizes the sum of the
producer surplus and
consumer surplus. The
effect of transmission
congestion is to create
market inefficiency.
Effects
Market Power:
If the generator can
successfully increase its profits
by strategic bidding or by any
means other than lowering its
costs, it is said to have market
power.
Congestion may lead to market
power which ultimately results
in market inefficiency.
EFFECTS : CONGESTION

8. FEATURES: SCHEMES/METHODS
 Any congestion management scheme should
try to accommodate the following features:
 Economic Efficiency:
It should minimize and achieve system
security, forgoing as little social welfare as
possible. The scheme should lead to both,
short term and long term efficiency.
 Be robust:
Scheme should be robust with respect to
strategic manipulation by the market entities.

9. FEATURES (Cont…)
 Non discriminative:
Each market participant should be treated
equally. For this, the network operator should
be independent of market parties and he
should not derive any kind of benefit from
occurrence of congestion.
 Be transparent:
The implementation should be well defined
and transparent for all participants.

10. CLASSIFICATION - METHODS
 Type of Contract
 First Come First
Serve
 Pro rata Methods
 Curtailment
Non-Market Market
 Explicit Auctions
 Nodal Pricing
 Zonal Pricing
 Price Area
 Re – dispatch
 Counter Trace

11. CONGESTION PROCESS
Determination of
Available
Transfer
Capability
Capacity
Allocation
Congestion
Allevation
Congestion
Forecast near Real
Time
Dispatch
Schedules
Bids or
Reservation

12. EXPLICIT AUCTIONEXPLICIT AUCTION11
IMPLICIT AUCTIONIMPLICIT AUCTION22
MARKET SPLITTINGMARKET SPLITTING33
COUNTER TRADECOUNTER TRADE44
METHODS: CONGESTION
RE-DISPATCHINGRE-DISPATCHING55
Pricing
Based
Remedial

13. EXPLICIT AUCTION
 The principal is selling the available capacity
of the tie line to the highest bidder.
 It separate the energy market from the
transmission capacity market.
 This is nothing but the auctioning the tie line
capacity.
 In this method, the system operator consider
the security analysis for the Available
Transmission Capacity (ATC).

14. EXPLICIT AUCTION (Cont…)
Limitations of the Explicit Auction are:
 There is increased complexity which may
complicate trading for the participants.
 This fails to account for parallel flow in
meshed networks.

15. IMPLICIT AUCTION
 The day ahead transmission capacity
integrates spot markets to maximise the
welfare of the markets.
 Implicit auctions ensure that electrical energy
flows from the surplus areas (low price areas)
towards the deficit areas (high price areas)
thus also leading to price convergence.
 Implicit auction signifies the concept used for
both ‘market coupling’ and ‘market splitting’.

16. MARKET SPLITTING
 Grid bottlenecks are relieved by comparison
of the calculated contractual flow with the
transmission capacity available for spot
trading, and
 If the flow exceeds the capacity, the prices
are adjusted on both sides of the bottleneck so
that the flow equals the capacity.

17. MARKET SPLITTING (Cont…)
 If the flow exceeds the capacity at the
common price for the whole market area, it
is split in a surplus part and a deficit part.
 The price is reduced in the surplus area
(sale > purchase) and increased in the
deficit area (purchase > sale).

18. COUNTER TRADE
 It uses same principle as Re-Dispatching
(Capacity Alleviation).
 This is market oriented, rather than using
command and control.
 This system uses buying and selling of
electricity at prices determined at bidding
process.
 The counter trading uses a principle of
replacing an ill-generator by a better
generator to reduce the congestion.

19. COUNTER TRADE (Cont…)
 The ISO has to buy electricity downstream at
higher cost and must sell it upstream.
 There is no congestion rent, only congestion
cost for ISO.
 It is used in the Norwegian system for real
time congestion management system.

20. RE-DISPATCHING
 It is based on the capacity alleviation method.
 This method relieve congestion in real time
and use remedial measures.
 It is exercised as a command and control
scheme.
 ISO (Independent System Operator) curtails
or increases injections without any market
based incentives.
 The ISO keep the re-dispatch cost low as an
incentive.

21. COMPARISION
Methods Characteristic Market
Based?
Allocation Alleviation Example
Explicit Decentralized
auctioning
YES YES NO European
Interconnection
Nodal
Pricing
Required
Centralized
Dispatch
YES YES NO England, New
York
Zonal
Pricing
Use Market
Splitting
YES YES NO Australia, Nordic
Pool, India (IEX)
Re-
dispatch
- YES NO YES -
Counter
Trade
Replacement
of ill placed
producer
YES NO YES Sweden
Pro-rata
Methods
Some norms of
allocation
NO NO YES Developing
Countries

22. CONCLUSION
 Efficient allocation of scarce transmission
capacity to the desired participants of the
market is one of the main objectives of
congestion management schemes.
 In the market based methods, the system
operator is bothered about the economical
efficiency of the generation re-adjustment
process.
 The non-market based methods are driven by
the simplicity and ease of procedure.

23. CONCLUSION (Cont…)
 The congestion management techniques are
strongly coupled to the overall market
design.
 The term - congestion management
generally refers to the capacity allocation to
various participants before finalizing the
actual schedules of nodal injections.
 Presently congestion management is a
challenging aspect in the deregulated
market.

24. THANK
YOU!