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

  • BSC Portal > Operational Data > TLF Determination information

Please note that the above data is uploaded to the BSC Portal which will require you to log in to access the information.

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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Get access to Transmission Loss Factors Determination Data on the Portal.


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