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ESO
Historic frequency data
This page holds historic frequency data for Great Britain at a 1 second resolution. N.B. 2019 data was updated on 14/2/2020 to correct for errors.
Data for 2020 onwards will be published on the National Grid ESO Data Portal: https://data.nationalgrideso.com/system/system-frequency-data.
2019
2018
Second-by-second frequency data for the calendar year 2018.
2017
Second-by-second frequency data for the calendar year 2017.
2016
Second-by-second frequency data for the calendar year 2016.
2015
Second-by-second frequency data for the calendar year 2015.
2014
Second-by-second frequency data for the calendar year 2014.