Trading period  Zone  Constraint name  Type  Limit (MW)  Shadow price ($/MWh)  

15  CNI  FK_HLY2201 HLY5_CTRLMAX  MnCnst  349.000  44.40  


15  LSI  NSY_ROX.1__CYD_TWZ1.1__CYD_TWZ1__ROX__LN  BrCnst  307.540  3.74  


19  LNI  BEN_HAYP2max  BrCnst  420.000  1.52  


19  LSI  BEN_HAYP2max  BrCnst  420.000  1.52  


27  LSI  NSY_ROX.1__CYD_TWZ2.1__CYD_TWZ2__ROX__LN  BrCnst  309.030  3.39  


33  LNI  BEN_HAYP2max  BrCnst  420.000  0.87  


33  LSI  BEN_HAYP2max  BrCnst  420.000  0.87  


34  LNI  BEN_HAYP2max  BrCnst  420.000  1.57  


34  LSI  BEN_HAYP2max  BrCnst  420.000  1.57  


40  LSI  NSY_ROX.1__CYD_TWZ1.1__CYD_TWZ1__ROX__LN  BrCnst  309.210  0.89  


41  LSI  NSY_ROX.1__CYD_TWZ2.1__CYD_TWZ2__ROX__LN  BrCnst  309.200  1.11  


47  CNI  FK_HLY2201 HLY5_CTRLMAX  MnCnst  346.000  36.87  

Trading period start  Trading period  Zone  Constraint name  Type  Factor  Component  MW  Limit (MW)  Shadow price ($/MWh) 

29/10/2020 07:00:00  15  CNI  FK_HLY2201 HLY5_CTRLMAX  MnCnst  1.00000  HLY2201 HLY5 [ENOF]  349.00000  349.0000000000  44.4000000000 
29/10/2020 07:00:00  15  LSI  NSY_ROX.1__CYD_TWZ1.1__CYD_TWZ1__ROX__LN  BrCnst  0.34900  CYD_TWZ1.1  202.49000  307.5400000000  3.7400000000 
29/10/2020 07:00:00  15  LSI  NSY_ROX.1__CYD_TWZ1.1__CYD_TWZ1__ROX__LN  BrCnst  1.31600  NSY_ROX.1  179.99300  307.5400000000  3.7400000000 
29/10/2020 09:00:00  19  LNI  BEN_HAYP2max  BrCnst  1.00000  BEN_HAY2.1  420.00000  420.0000000000  1.5162000000 
29/10/2020 09:00:00  19  LSI  BEN_HAYP2max  BrCnst  1.00000  BEN_HAY2.1  420.00000  420.0000000000  1.5162000000 
29/10/2020 13:00:00  27  LSI  NSY_ROX.1__CYD_TWZ2.1__CYD_TWZ2__ROX__LN  BrCnst  0.35200  CYD_TWZ2.1  201.75800  309.0300000000  3.3908000000 
29/10/2020 13:00:00  27  LSI  NSY_ROX.1__CYD_TWZ2.1__CYD_TWZ2__ROX__LN  BrCnst  1.31700  NSY_ROX.1  180.72200  309.0300000000  3.3908000000 
29/10/2020 16:00:00  33  LNI  BEN_HAYP2max  BrCnst  1.00000  BEN_HAY2.1  420.00000  420.0000000000  0.8726000000 
29/10/2020 16:00:00  33  LSI  BEN_HAYP2max  BrCnst  1.00000  BEN_HAY2.1  420.00000  420.0000000000  0.8726000000 
29/10/2020 16:30:00  34  LNI  BEN_HAYP2max  BrCnst  1.00000  BEN_HAY2.1  420.00000  420.0000000000  1.5650000000 
29/10/2020 16:30:00  34  LSI  BEN_HAYP2max  BrCnst  1.00000  BEN_HAY2.1  420.00000  420.0000000000  1.5650000000 
29/10/2020 19:30:00  40  LSI  NSY_ROX.1__CYD_TWZ1.1__CYD_TWZ1__ROX__LN  BrCnst  0.34500  CYD_TWZ1.1  204.18700  309.2100000000  0.8870000000 
29/10/2020 19:30:00  40  LSI  NSY_ROX.1__CYD_TWZ1.1__CYD_TWZ1__ROX__LN  BrCnst  1.31800  NSY_ROX.1  181.15700  309.2100000000  0.8870000000 
29/10/2020 20:00:00  41  LSI  NSY_ROX.1__CYD_TWZ2.1__CYD_TWZ2__ROX__LN  BrCnst  0.34300  CYD_TWZ2.1  204.87500  309.2000000000  1.1072000000 
29/10/2020 20:00:00  41  LSI  NSY_ROX.1__CYD_TWZ2.1__CYD_TWZ2__ROX__LN  BrCnst  1.31800  NSY_ROX.1  181.28100  309.2000000000  1.1072000000 
29/10/2020 23:00:00  47  CNI  FK_HLY2201 HLY5_CTRLMAX  MnCnst  1.00000  HLY2201 HLY5 [ENOF]  346.00000  346.0000000000  36.8695000000 
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Binding transmission and market node constraints in the SPD solution for final pricing are described in this report. The technical parameters for each constraint are presented.
Constraints in the SPD model fall into one of three categories:
Only the instances of the above constraints that are binding in the SPD solution for final pricing are presented in this report. A constraint is determined to be binding if its associated shadow price is positive. On any given day, there may well be no binding constraints of any or all of the three constraint types. Binding branch limits are quite rare.
Limit (MW) denotes the megawatt value of the transfer capacity parameter for branch constraints and branch limits, and the generating machine limit net of the frequency keeping requirement in the case of market node constraints (i.e. the righthand side of the constraint).
Shadow price ($/MWh) is a measure of the cost to the system of a binding constraint. Conversely, a constraint that is not binding will have a zero shadow price and imposes no cost on the system. More technically, the shadow price represents the decrease (increase) in the SPD objective function value that would be associated with a 1 MW increase (decrease) in the limit of the constraint. Shading is set between zero (white), $100 (yellow), and $200 (red) on the shadow price as a visual cue indicating the severity of boundedness. Historically, approximately 80% of all binding constraints have a shadow price of less than $200/MWh.
The components that the constraint is composed of (i.e. the lefthand side) can be viewed by clicking on the plus sign at the left to expand the row:
The sum (over all components) of the factor multiplied by the MW for each component will equal the limit or righthand side parameter for a constraint that is binding.
If a branch or branch limit constraint spans two zones, the constraint will appear in the report twice; once for each zone.
Downloading the report as a CSV or PDF does not capture the components of the constraints. To obtain all details of binding constraints, including its components, and to select binding constraints for more than a single day, please use the underlying data report (icon at upper right of screen).
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