Transcript Access to the Transmission Network and Management of

International Council on Large Electric Systems
Brasilia Workshop
TRANSMISSION ACCESS AND
CONGESTION MANAGEMENT
O. Lavoine-RTE-France
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
What is congestion ?
First of all, congestion is
•an operational technical problem : the network can not
accommodate all the requested withdrawals and
injections,
•due to the fact that security criteria must be respected :
•N-1 or more,
•Voltage.
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
Technical means to solve a
congestion
In the daily operation :
• Topological modifications,
• Modification of the requested withdrawals and
injections (by re-dispatching).
In a longer term :
• Modifications of the maintenance plans (for generation
plants and for network elements),
• Development of new lines (when possible !).
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
Main economical consequences of a
congestion
In a competitive markets on
both sides of the congestion
Low electricity price
zone
Congestio
n : lack of
capacity
Decoupling of markets,
Congestion rent =
Difference of price *
Transmission Capacity
High electricity price
zone
22 September 2003
If in the south, the market is
not competitive
Low electricity price
zone
Need of a strong
regulation to reduce
market power !
Market power of some
power plants
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
Two majors different situations
An easy situation :
The congestion is inside a control area,
All technical means can be controlled by one
centralized control centre.
A much more difficult situation :
The congestion is at the limit of two (or more)
countries,
There is a strong need to co-ordinate control centres
and market mechanisms.
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
Economic principles
The treatment of congestion should respect the following
theoretical economic principles:
•Efficiency (application of nodal pricing approaches ?),
•Limit power markets,
•No discrimination.
Practically, any system must be easily understandable by
concerned users.
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
Example of an internal congestion :
South-East of France
400 kV line
225 kV line
Rhône
Valley
Boutre
Congestion
N-1 line
Nice
Marseilles
Toulon
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
Example of an international
congestion : The Alps to Italy
Limited Capacity
(The Alps)
France, Germany,
Switzerland : low
price
Italy : high price
22 September 2003
Brasilia Workshop
International Council on Large Electric Systems
Brasilia Workshop
CIGRE C5 objectives
•CIGRE SC 5 has formed a dedicated WG to congestion
questions with experts coming from many different
countries.
•A first objective is to have a worldwide state of art of
experiences.
•A second objective is to classify these experiences
according to different situations.
•Each time, national and international situations have to
be considered.
22 September 2003
Brasilia Workshop