1. Nexus Requirements To support the current business processes
We need to maintain performance and enable market operation as is
To enable movement to a fully smart/AMR world
Can see an end point where technology supports allocation and reconciliation by meter point
To support interim processes through the change period
Nexus would be required to permit migration from “AS IS” to “TO BE”

2. Require nomination for large sites
Current Requirements
Require nomination for large sites
Aggregate nomination to match Nationalgrid allocation for NDM sites
Reconciliation at supply point level for large supply points and in aggregate for small supply points
Historic requirements to enable domestic competition
07 April 2019, E.ON, Page 2

3. Requirement for change Balancing:
AMR and smart metering are improving information access
Modifications to enable greater numbers of elective DM sites move away from aggregate nomination by Transporters to Shipper responsibility
Reconciliation:
RbD was the subject of an Ofgem review and an issues log
Technology is significantly improved from 1998
Comparisons to electricity balancing support a move away from aggregate reconciliation
RbD has been the subject of a number of modifications recently focusing on disproportionate risk to market sectors
07 April 2019, E.ON, Page 3

4. Overview of main timeline
2014
AMR installation
Move to nominating day ahead for all sites
MP Rec for most sites
Smear for unknown
RbD for remaining SSP sites
2010
Allocation
Reconciliation (MPRec and RbD)
2020
Nominating all sites
MP Rec for all sites
Smear for losses

5. Issues for consideration
How to move from the current process to the desired process
Nominations are already required – these can be used to replace allocations as per the current DM process
RbD has limitations and these will become greater as more sites move into individual meter point reconciliation, instigating the losses calculation earlier will remove challenges from those with sites left in the RbD process until later in the timeline
End point has to be meter point reconciliation for all sites
Would expect Nexus process to cover requirements to support move to world