Pool strategy of an electricity producer with endogenous formation - - PowerPoint PPT Presentation
Pool strategy of an electricity producer with endogenous formation - - PowerPoint PPT Presentation
Pool strategy of an electricity producer with endogenous formation of clearing prices Antonio J. Conejo, Carlos Ruiz University of Castilla-La Mancha, Spain, 2011 Contents Background and Aim Approach Model Features Model
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 2
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 3
Background and Aim
- Comparatively large number of generating units
- Units distributed throughout the power network
29/04/2011 4
Strategic power producer
Background and Aim
- Cleared once a day, one-day ahead and on a
hourly basis
- DC representation of the network including first
and second Kirchhoff laws
- Hourly Locational Marginal Prices (LMPs)
29/04/2011 5
Pool-based electricity market
Background and Aim
4/29/2011 6
Pool-based electricity market Strategic power producer
Best offering strategy to maximize profit
Background and Aim
- Considering the market: MPEC
formulation
- Considering the real-world: Stochastic
formulation
- Stochastic MPEC!
29/04/2011 7
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 8
Approach
4/29/2011 9
Social Welfare Maximization (Market Clearing)
Profit Maximization
Upper-Level Lower-Level
Bilevel model:
subject to
LMPs Offering curve Dual Variables
Approach
- Bilevel model: Optimization problem
constrained by other optimization problem (OPcOP)!
OPcOP
11
Approach
4/29/2011 12
Profit Maximization
Upper-Level
MPEC:
LMPs
KKT Conditions
Offering curve
subject to
MPEC
13
MPEC
14
Contents
- Background and Aim
- Approach
- Model Features
- Model Structure
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 15
Features
1) Strategic offering for a producer in a pool with endogenous formation of LMPs. 2) Uncertainty of demand bids and rival production
- ffers.
3) MPEC approach under multi-period, network- constrained pool clearing. 4) MPEC transformed into an equivalent MILP.
29/04/2011 16
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 17
Deterministic Model
4/29/2011 18
Upper-Level → Profit Maximization:
Costs - Revenues Ramping Limits Price = Balance dual variable
Deterministic Model
29/04/2011 19
Upper-Level → Profit Maximization:
Dual variable
Deterministic Model
29/04/2011 20
Lower-Level → Market Clearing
Maximize Social Welfare Power Balance
Deterministic Model
29/04/2011 21
Lower-Level → Market Clearing
Price
Deterministic Model
4/29/2011 22
Production / Demand Power Limits Transmission Capacity Limits Angle Limits
Lower-Level → Market Clearing
Deterministic Model
29/04/2011 23
Lower-Level → Market Clearing
Deterministic Model
29/04/2011 24
Lower-Level → Market Clearing → KKT conditions
Deterministic Model
29/04/2011 25
Lower-Level → Market Clearing → KKT conditions
Deterministic Model
29/04/2011 26
KKT Lower-Level
MPEC model
Deterministic Model
4/29/2011 27
The MPEC includes the following non-linearities: 1) The complementarity conditions ( ). 2) The term in the objective function.
Linearizations
b a
Deterministic Model
4/29/2011 28
1 , ) 1 ( u M u b uM a b a b a
M Large enough constant (but not too large)
Linearizations → Complementarity Conditions
Fortuny-Amat transformation
Deterministic Model
29/04/2011 29
Based on the strong duality theorem and some of the KKT equalities
Linearizations → Term:
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 30
Stochastic Model
- Consumers’ bids
- Rival producers’ offers
29/04/2011 31
Uncertainty incorporated using a set of scenarios modeling different realizations of:
Pairs of production quantities ( ) and market prices ( ).
Stochastic Model
4/29/2011 32
Deterministic model for each scenario
tn Building of the optimal offering curve
S tib
P
Stochastic Model
29/04/2011 33
Optimal
- ffering
curve
Stochastic Model
4/29/2011 34
To ensure that the final offering curves are increasing in price some additional constraints are needed: These constraints link the individual problems increasing the computational complexity of the model.
Stochastic Model Math Structure
4/29/2011 35
Stochastic Model Math Structure
4/29/2011 36
Stochastic Model Math Structure
4/29/2011 37
- 1. Direct solution: CPLEX, XPRESS
- 2. Decomposition procedures (Lagrangian Relaxation)
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 38
Examples
29/04/2011 39
Six-bus test system→ electricity network
Examples
29/04/2011 40
Six-bus test system→ demand curve
Examples
29/04/2011 41
Six-bus test system→ generating units
Examples
4/29/2011 42
The maximum power flow through lines 2-4, 3-6 and 4-6 are 269.62, 229.44 and 39.6933 MW respectively
Six-bus test system→ uncongested network results
Examples
29/04/2011 43
Six-bus test system→ uncongested network results
Examples
29/04/2011 44
Capacity of line 3-6 limited to 230 MW:
Six-bus test system→ congested network results
Examples
29/04/2011 45
Capacity of line 3-6 limited to 230 MW:
Six-bus test system→ congested network results
Examples
29/04/2011 46
Capacity of line 4-6 limited to 39 MW:
Six-bus test system→ congested network results
Examples
- Uncongested network case
- 8 equally probable scenarios
- They differ on the rival producer offers ( ) and
- n the consumer bids ( )
- Selected to obtain a wide range of prices
29/04/2011 47
Six-bus test system→ stochastic model
D tdk
O tjb
Examples
29/04/2011 48
Six-bus test system→ stochastic model results
Examples
29/04/2011 49
Six-bus test system→ stochastic model results
Offering curves for strategic generator 1
Examples
29/04/2011 50
Six-bus test system→ stochastic model results
Offering curves for strategic generator 1
Examples
- 24 Nodes
- 8 strategic units
- 24 non-strategic
units
- 17 consumers
- 24 hours
29/04/2011 51
IEEE One Area Reliability Test System
Examples
29/04/2011 52
IEEE One Area Reliability Test System → Results
Examples
29/04/2011 53
IEEE One Area Reliability Test System → Results
Marginal cost offer Strategic offer
Examples
- Model solved using CPLEX 11.0.1 under GAMS on a
Sun Fire X4600 M2 with 4 processors at 2.60 GHz and 32 GB of RAM.
4/29/2011 54
Model 6-bus uncongested 6-bus congested 6-bus stochastic IEEE RTS CPU Time [s] 2.91 5.82 204.77 449.33
Computational issues
Contents
- Background and Aim
- Approach
- Model Features
- Model Formulation
– Deterministic – Stochastic
- Examples
- Conclusions
29/04/2011 55
Conclusions
- Procedure to derive strategic offers for a power
producer in a network constrained pool market.
– LMPs are endogenously generated: MPEC approach. – Uncertainty is taken into account. – Resulting MILP problem.
- Exercising market power results in higher profit and
lower production.
- Network congestion can be used to further increase
profit.
29/04/2011 56
29/04/2011 57
Thanks for your attention!
http://www.uclm.es/area/gsee/web/antonio.htm
Appendix A Computational Issues
- Model has been solved using CPLEX 11.0.1 under GAMS on a
Sun Fire X4600 M2 with 4 processors at 2.60 GHz and 32 GB
- f RAM.
- The computational times are highly dependent on the values
- f the linearization constants M.
4/29/2011 58
Model 6-bus uncongested 6-bus congested 6-bus stochastic IEEE RTS CPU Time [s] 2.91 5.82 204.77 449.33
Appendix A Computational Issues
- 1. Solve a (single-level) market clearing considering that
all the producers offer at marginal cost.
- 2. Obtain the marginal value of each relevant constraint.
- 3. Compute the value of each relevant constant as:
4/29/2011 59
100
1 value variable dual M
Heuristic to determine the value of M:
Appendix B Stochastic model
29/04/2011 60
Appendix B Stochastic model
29/04/2011 61
Appendix B Stochastic model
29/04/2011 62