1. 1 Mod_18_10 : Intra Day Trading in the SEM Working Group 4 August 19 th 2010 SEMO High-Level Impact Assessment

2. 2 Actions from Working Group 3 ●At WG3 SEMO took an action to document the options below and obtain a high-level impact assessment following compliance check by RAs: ●Group options A:  Option 1A – Unused I/C Capacity Reassignment;  Option 1B – I/C updated bids; ●Group options B  Participant Option 2 – Split SEM Day; and  Option SEMO – Split SEM Day for Interconnector Trading.  Option TSO1 – Additional Interconnector Trading Opportunities; and  Option TSO2 – Additional Interconnector Trading Opportunities allowing System Security Actions. ●“Light” IA for Participant Option 3 Alignment with EFAs

3. 3 Actions from Working Group 3 ●The Options were documented in the paper: “Intra-Day Trading Options for Impact Assessment” ●SEMO then commenced Impact Assessment of all options ●On 4th August, RAs issued a note: “Compliance with the Congestion Management Guidelines and Impact Assessment of Intra Day Options”, which ruled Group options A as being non- compliant ●On receipt of this note, SEMO directed the vendor to discontinue assessment of the Group A options ●In the paper “Intra-Day Trading Options for Impact Assessment”, Group B options were designated as Option Group 1 – with two variants for analysis  IU participation only and  All Generator User participation ●Participant Option 3 was designated as Option Group 2 – again with two variants for analysis  IU participation only and  All Generator User participation ●Impact assessment was continued with the vendor for Option Group 1 and Option Group 2 and SEMO considered its operational impact

4. 4 Overview of Options Assessed ●Option Group 1  One Gate Closure on TD-1 (TD-1 AM : EA1)  Additional Gate Closure on TD-1 (TD-1 PM : EA2)  Additional Gate Closure on TD (TD AM : WD1) ●Variant 1: Interconnector Unit Participation Only ●Variant 2: All Generator Unit Participation

5. 5 Overview of Options Assessed (cont’d) ●Option Group 2  One Gate Closure on TD-1 (TD-1 AM : EA1)  Additional six Gate Closures on TD, covering an appropriate Optimisation Time Horizon (which could be 30 hours or less, depending on the impacts on the optimisation), starting in four hours time (TD AM : WD1 to WD6) ●Variant 1: Interconnector Unit Participation Only ●Variant 2: All Generator Unit Participation

6. 6 Impact Assessments ●Caveat:  The following is a high-level impact assessment based on available information and is subject to change based on detailed design

7. 7 Impact Assessments ●Option Group 1 Central Market System Impacts

8. 8 Option Group 1 – Areas of Central Market System affected (both IUs only and All Users) InterfaceAffects MP-SMO Interface (Submissions) SEMO, MPs MI ApplicationsSEMO MI DatabaseSEMO TSO-SMO interfaceTSOs, IA & SEMO IA-SMO interfaceIA, SEMO MA DSI - MI InterfaceSEMO MA DSP - MI InterfaceSEMO MI_MOI interfaceSEMO MI-Settlement interfaceSEMO MI-MP Interface (Report publication) MPs SMO-TSO InterfaceTSOs, SEMO SMO-IA InterfaceIA, SEMO

9. 9 Option Group 1 (IUs only) : MP-SMO Interface (MPs & SEMO) ●MP-SMO Interface:  Provision for 3 gate-windows : GW1 (existing gate window), GW2 (EA2 gate window) and GW3 (WD gate window)  Enhance Interconnector Unit (IU) submissions to include an indicator which specifies the gate-window in to which MPs are submitting IU data  Enhance the IU submission to include provision for an extra flag to indicate whether the MP wants to protect schedules from the previous runs  Change XML Schema, MPI displays, validations and underlying data structures to allow IUs to be resubmitted in the two new GWs  Ensure consistency between Type II and Type III communication  Possible validation on changes in Price between gates  Unresolved Issue: Max number of (P, Q) pairs for IUs in (P,Q) curve reconstruction?

10. 10 Option Group 1(IUs only) : MI Applications (SEMO) ●MI Applications: ●Add additional and/or modify existing events in the Event Manager to manage the market timelines to allow IU re-submissions ●Possible modification of market status display with “Open/Close” status ●Possible additional validations on (P,Q) pairs in subsequent submissions that correlate to a certain percentage

11. 11 Option Group 1(IUs only) : MI Database (SEMO) ●MI Database : ●IU tables changes to support gate-window indicator and schedule protection flag  Each set of MP IU Offer submissions will be preserved in the database with an indicator field ●New tables – both operational and audit – to store the (P,Q) pairs computed by MA Ex-post applications ●Possible new mapping table to map the incoming gate-window numbers to run_types in MA

12. 12 Option Group 1(IUs only) : TSO-SMO interface (TSOs & SEMO) ●TSO-SMO interface: ●Support new submissions for load forecast and wind forecast during the additional Ex-Ante and WD1 gate window (gate-window indicator fields etc.)

13. 13 Option Group 1(IUs only): IA-SMO interface (IA & SEMO) ●IA-SMO interface: ●Timeline changes to IA submissions for Ex-Ante runs: Support new IA submissions for Modified Interconnector User Nominations (MIUN) datasets for Ex-Ante Sequence and WD1 runs

14. 14 Option Group 1 (IUs only): MA DSI - MI Interface (SEMO) MA DSI - MI Interface: ●Creation of amended curves for Ex-Post UUC

15. 15 Option Group 1 (IUs only): MA DSP - MI Interface (SEMO) MA DSP - MI Interface: ●For IUs, DSP will populate the (P, Q) pairs used for Ex-post runs at Trading Period resolution ●New tables will be created to store this data

16. 16 Option Group 1 (IUs only): MI_MOI interface: (SEMO) ●MI_MOI interface: ●Change the existing MI-MOI displays to show additional IU COD parameters and data sets – “Trading Day”, “Operational Day” and “Audit” tabs will be impacted ●Change the existing set of MI-MOI displays to render new set of TSO and IA inbound data to the MO via the MOI ●Create new of MI-MOI displays to display the (P, Q) pairs published by MA-DSP in the Ex-Post run

17. 17 Option Group 1 (IUs only): MI-Settlement interface (SEMO) ●MI-Settlement interface: ●All TOD and COD pushed to Settlement

18. 18 Option Group 1 (IUs only): MI-MP Interface (Report publication): (Significant MP impact) ●MI-MP Interface (Report publication): ●Publication of new COD sets for multiple gate-windows for Interconnector Units. ●Multiple new reports to publish additional load and wind forecasts ●New reports to include Market Schedule summary, System Marginal Price and Shadow Prices from both the EA2 and WD1 reports to General Public ●New reports to include Market Schedule detail, Interconnector user nominations, and Modified Interconnector Unit Nominations from both the EA2 and WD1 reports to MPs ●Create new reports or update existing reports to include Modified Interconnector Unit Nominations received from the IA subsequent to both the EA2 and WD1 runs to MPs and General Public ●Create new reports to publish the (P, Q) pairs at the Trading Period level for Interconnector Units computed by MA Ex-post application to MPs

19. 19 Option Group 1 (IUs only): SMO-TSO Interface (TSOs & SEMO) ●SMO-TSO Interface: ●Publish a new set of data for IU bids and offers with gate-windows submitted for the EA2 run to TSOs ●Publish a new set of data for IU bids and offers with gate-windows submitted for the WD1 run to TSOs -- TSO will need to exclude the (P,Q) curves not utilized by the SEM systems ●Publish new sets of data for MIUNs received from the IA subsequent to the EA2 and WD1 runs to the TSOs ●Publish a new set of Market schedules from the EA2 and WD1 runs to the TSOs

20. 20 Option Group 1 (IUs only): SMO-IA Interface (IA & SEMO) ●SMO-IA Interface: ●Publish new sets of outbound data i.e., IUNs from the EA2 and WD1 runs to the IAs ●MI-IA Interface: ●Publish a new set of EA2 reports to IAs ●Publish a new set of WD1 reports to IAs

21. 21 Option Group 1 (All Generator Participation): ●All Changes as for Option Group 1 IU Users only  plus additional changes to: MP-SMO Interface: (changes to Gen Offer submissions, MPI displays) MI Database:(GW indicator for Gens, additional (P,Q) storage) MA DSI – MI Interface: ( (P,Q) curves for Ex-Post UUC) MA DSP - MI Interface: (different MA logic to compute (P,Q) curves for Gens new tables for (P,Q) pairs) MI_MOI interface:(new displays for Gen Offer parameters) MI-Settlement interface:(additional Gen (P,Q) pairs included in settlement push) MI-MP Interface : (additional report publication)

22. 22 Outstanding Issues ●Number of (P,Q) points in reconstructed curves/implementation of this ●Performance impact on existing environments – hardware refresh has been recommended ●Further consideration required for Settlements, particularly in the determination of constraints and the implementation of the reconstruction of PQ Pairs

23. 23 Impact Assessments ●Option Group 1 Operational Impacts

24. 24 SEMO Operational Impacts Below is a high-level impact assessment of the impact of Option Group 1 on SEMO Operations: Pricing and Scheduling/Settlement ●Additional Resources and changes in shift pattern ●New business processes and work procedures for additional runs ●Accommodation requirements may need to be considered ●Staff Training ●Market Participant training  Multiple bid submission  Interpretation of new reports  Querying of data ●Increased workload to process and check the EA and WD inputs to settlement and resolve queries from additional runs ●User Acceptance Testing (in addition to normal testing) ●Parallel running of old and new systems for over 14 months (Repricing / Re-settlement) ●Project readiness impacts ●The cancellation of SRAs will need to be automated ●Credit Cover review

25. 25 SEMO Operational Impacts Below is a high-level impact assessment of the impact of Option Group 1 on SEMO IT: ●Resources – previous projects of this scale had consultant resources ●Finite capacity of vendor to deliver both scheduled releases and Intra- Day Trading ●Hardware refresh has been recommended ●Operational / Market IT Support to be extended to cover a longer operational window for Market Operations

26. 26 Impact Assessments ●Option Group 2 Central Market System Impacts

27. 27 As for Option Group 1, Option Group 2 will affect the following areas of the CMS InterfaceAffects MP-SMO Interface (Submissions) SEMO, MPs MI ApplicationsSEMO MI DatabaseSEMO TSO-SMO interfaceTSOs, IA & SEMO IA-SMO interfaceIA, SEMO MA DSI - MI InterfaceSEMO MA DSP - MI InterfaceSEMO MI_MOI interfaceSEMO MI-Settlement interfaceSEMO MI-MP Interface (Report publication) MPs SMO-TSO InterfaceTSOs, SEMO SMO-IA InterfaceIA, SEMO

28. 28 Option Group 2 Additional Issues ●The vendor has concerns regarding scalability vis-a-vis (P,Q) points ●The maximum number of PQ pairs currently allowed in MA is 10  With the COD reconstruction logic, the number of PQ pairs can be as many as n * 10, where n is the number of runs  For Option Group 2, this becomes 70 (P,Q) pairs

29. 29 Impact Assessments ●Option Group 2 Operational Impacts

30. 30 SEMO Operational Impacts Below is a high-level impact assessment of the impact of Option Group 2 on SEMO Operations: ●Significant additional resources and 24 hour operations 365 days a year ●Accommodation requirements may need to be considered ●Complete redesign of business processes and work procedures for additional runs ●Dual Processing of Pricing runs ( Ex-Post and EA1 will be parallel) ●Staff Training ●Market Participant training  Multiple bid submission  Interpretation of new reports  Querying of data ●Increased workload to process and check outputs and outputs in Pricing and settlement and resolve queries from additional runs ●User Acceptance Testing (in addition to normal testing) ●Parallel running of old and New systems for over 14 months ●Project readiness impacts ●The cancellation of SRAs will need to be automated ●Credit Cover review ●Significant changes to the TSC which will need to incorporated into the Operational processes

31. Other Operational Impacts for both Options ●Credit cover requirements will need to be revisited ●The impact on the choice of MSP solver (MIP & LR) ●Edge effects - in particular for Option Group 2 (6 WD gates) ●Additional criteria – solution time and gates - in particular for Option Group 2 (6 WD gates)

32. Summary – Option Group 1 ●Option 1 (both Variants)  Is compliant with CMG  Less change than Option Group 2 (both CMS and operational) therefore less expensive  Less change than Option Group 2 for Market Participants  Offers less risk  Lower Impact on the SEM  Can be delivered in a shorter time frame  European markets in a state of flux – least expensive option that delivers compliance with minimal change to the SEM would be preferable pending outcomes of European Regional Developments

33. Summary – Option Group 2 ●Option 2 (both Variants)  Is compliant with CMG  More change than Option Group 1 (both CMS and operational) therefore more expensive  More change than Option Group 1 for Market Participants  Incurs more risk  Significant Impact on the SEM (24*7, Operational considerations)  Will take longer to deliver  More complex  Outstanding scalability concerns from vendors  European markets in a state of flux – implementing a more expensive option with significant change to the SEM may not be prudent at this point pending outcomes of European Regional Developments

34. Proposed Next Steps ●To ensure compliant Intra-Day Trading is delivered, the following are required:  Imminent industry agreement and decision on the Option to implement  Timely Regulatory Approval  Early agreement on Central Market System development as Intra-Day Trading is developed and implemented (future release planning) SEMO to proceed to full impact assessment of preferred option and initiate design with vendors Early communication of final design with Industry to progress MP impact assessments