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  • Triad Data

  • This area contains data used by National Grid to calculate Triads in accordance with the Statement of Use of System Charging Methodology (see section 14 of the CUSC).

    The Triads are the three half-hour settlement periods with highest system demand and are used by National Grid to determine charges for demand customers with half-hour metering and payments to licence exempt distributed generation.  They can occur in any half-hour on any day between November to February inclusive but are separated from each other by at least ten full days.

    The Triads are determined after the event using Elexon settlement metering data for November to February.  This data is usually available around 24 March following which National Grid will confirm the Triad half-hours.  Once confirmed they are not updated for subsequent settlement data.  Indicative Triads based on data received to date can be found on Elexon's Electricity Data Summary.

  • If you have any feedback on this web page, suggestions for ways to improve it or queries relating to this page then please contact Charging.Enquiries@NationalGrid.com
  • 27 Mar 2017
    2016-17 Triad Data
    325 KB

    24 Mar 2016
    2015-16 Triad Data
    163 KB

    27 Mar 2015
    2014-15 Triad Data
    74 KB

    01 Apr 2014
    2013-14 Triad data
    61 KB

    31 Mar 2014
    2012-13 Triad Data
    92 KB

    02 Oct 2013
    2011-12 Triad Data
    26 KB

    03 Oct 2013
    2010-11 Triad Data
    26 KB

    02 Oct 2013
    2009-10 Triad Data
    26 KB

    02 Oct 2013
    2008-09 Triad Data
    26 KB

    02 Oct 2013
    2007-08 Triad Data
    26 KB

    03 Oct 2013
    Triad calculation methodology
    82 KB

    19 Mar 2015
    Triad Dates
    13 KB


  • Many of the files available to download on this page are Acrobat PDF files. To access these you will need Acrobat Reader which is available from the Adobe web site.