Project Nexus Workgroup Reconciliation Meeting 6 Options for CSEP Reconciliation 24/04/2019

Background Reconciliation Business Requirements Document states “aspiration for new reconciliation rules to apply to NDM CSEPs” Preferred Shipper option is for a single Supply Point Register to hold CSEP meter point data and facilitate Meter Point Rec Need to develop “Contingency Requirements” for SSP/LSP CSEP meter point rec, in case single SP Register is not achieved

Current CSEPs Reconciliation Arrangements Larger Supply Points Each LSP = 1 Logical Meter Number (LMN) iGT holds meter assets and reads iGT sends start and end dates and actual volumes GT agent calculates Rec volume, Rec energy and Rec charges Opposite entry passed to RbD Smaller Supply Points 1 LMN per Shipper/CSEP project combination CSEP SSP AQ included in RbD – ranks equally with direct connects for RbD charging

Options for Future CSEP SSP Rec No Meter Point Rec for SSP on CSEPs – attract share of Reconciliation Neutrality A B Reconciliation on AQ, for every AQ change Aggregated Rec by SSP LMN – iGT Reads all meters in a CSEP on same day and submits total actual volume C D Meter installed at every offtake – Reconciliation between GT and iGT E Each SSP = 1 LMN – iGT submits dates and actual volumes F Single Supply Point Register allows full Meter Point Rec

Option A No Meter Point Rec for SSP on CSEPs – attract share of Reconciliation Neutrality only (in proportion to original allocation) Pros Simple solution No change to SPA arrangements No extra burden on iGT Cons No account taken of changes in gas usage No correction for erroneous AQs

Option B Reconciliation on AQ, for every AQ change. Following an AQ change, iGT advises Xoserve of old and new AQ, applicable start dates and applicable Shippers. Difference in AQ billed as a change to allocation, split between applicable Shippers. Separate process to LMN AQ updates. Pros Simple solution Not dependent on change to SPA arrangements Takes account of changes in usage and Shipper transfers Cons No check against LMN AQ updates Extra burden on iGT Relies on timely and accurate AQ reviews by iGT

Option C Aggregated Rec by SSP LMN – iGT Reads all meters in a CSEP on same day and submits total actual volume Pros Not dependent on change to SPA arrangements Takes account of changes in usage and Shipper transfers Cons Increased burden on iGTs Unfeasible to read all meters one day? Reconciliations not visible at MPR level

Option D Meter installed at every offtake – Reconciliation between GT and iGT? iGT to perform individual meter point reconciliations? Pros No change to SPA arrangements Clarity of large GT throughput Cons Large scale engineering project Does not help attribute energy to individual meter points Increased burden on iGTs

Option E Each SSP = 1 LMN – iGT submits dates and actual volumes – increase in data held in Gemini or other system Pros Takes account of changes in usage and Shipper transfers Visibility of meter point transactions Cons Increased burden on iGTs Meter asset data still held across diverse systems Large increase in data processing for 1m+ MPRs

Option F Single Supply Point Register for all direct and CSEP MPRs - allows full Meter Point Rec Pros Takes account of changes in usage and Shipper transfers Visibility of meter point transactions Cons Significant change to iGT processes Funding and governance not resolved

Option A - Illustration No Meter Point Rec for SSP on CSEPs – but attract share of Reconciliation Neutrality Initial Allocation – not to scale Prod 1&2 Prod 4 Prod 3 NDM CSEP SSPs

Option A - Illustration After Reconciliation CSEP SSPs share in changes to Unidentified Energy via Reconciliation Neutrality No other changes to CSEP SSP Allocation Prod 1&2 Prod 4 Prod 3 NDM CSEP SSPs Not to scale

Option B - Illustration Option B – Reconciliation on each change of AQ Assume Quarterly Rolling AQ for illustration only iGT sends updated Shipper AQ totals to Xoserve for use in daily allocation Separate notification to Xoserve of before- and after-AQs for SSPs Also highlight any Shipper changes in the period

Option B - Illustration Xoserve performs “AQ change Reconciliation” Similar to End of Year Threshold Crosser Reconciliation Reconcile for difference in allocation between old and new AQ Take account of Shipper changes Opposite energy amount feeds into Reconciliation Neutrality Prod 1&2 Prod 4 Prod 3 NDM CSEP SSPs Reconciliation based on AQ movements Not to scale