Consultation: P350 Draft Reference Network Mapping Statement 2024-25

This consultation seeks views on the draft reference Network Mapping Statement (NMS) for use in the allocation of Transmission Loss Factors (TLFs) for BSC Year 2024-2025.



No responses were received and therefore the draft network mapping statement will be taken to the next Imbalance Settlement Group (ISG) meeting to seek approval for it to be used for the BSC Year 2024/25.

Original consultation

Who will this impact?

Trading parties are invited to express their views on this draft reference Network Mapping Statement, in particular whether they agree with the following:

  • Volume Allocation Unit (VAU) to Node Mapping
  • Node to Zone Mapping
  • BM Unit to Zone Mapping
  • That the draft reference network mapping statement achieves the requirements detailed in the P350 legal text (paragraph 4.3 of Annex T-2 of the BSC)

About the Network Mapping Statement

The NMS uses historic data from a ‘Reference Year’ (RY), running from 1 September to 31 August each year, for use in the following BSC Year.

This NMS contains data relating to the RY 2022-23 for use in the BSC Year 2024-25.

The VAU to Node mappings are used to convert Metered Volume data for Volume Allocation Units into power flows by Node. These power flows by Node, along with associated Network Data provided by the NETSO, and the Distribution System Operator, are used to derive Nodal Transmission Loss Factors (TLFs) through use of the Load Flow Model (LFM), as defined in the LFM Specification.

Once the Load Flow Model has been run, Node to Zone mappings are used to derive Zonal TLFs from Nodal TLFs and Zone to Balancing Mechanism (BM) Unit mappings are used to allocate a TLF to every BM Unit.


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