Transmission Loss Factors Determination Data


This page details all the relevant data that is available to the industry for the determination of Transmission Loss Factors (TLFs).

The information is in response to Modification P350 ‘Introduction of a seasonal Zonal Transmission Losses scheme’ which introduces a Transmission Loss Factor (TLF) for each TLF Zone and BSC Season.

TLFs and Associated Data

Latest TLF determination data

Previous TLF determination data

The above data is uploaded to the Elexon Portal (login required).

ETLMO Values

The Approved Estimated Transmission Losses Adjustment (ETLMO) values are used by the Balancing Mechanism Reporting Agent (BMRA) to calculate indicative charges and payments for Balancing Mechanism (BM) actions, and the Energy Imbalance Price, in near to real-time.

These are updated on an annual basis and are approved by the Imbalance Settlement Group (ISG).

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