System Frequency
This page holds the historic system frequency data for Great Britain at a 1 second resolution. It is the role of the National Grid ESO to keep the system frequency at 50 Hz, with a statutory limit of 0.5 Hz above or below this value.
Time values are all given in Greenwich Mean Time (GMT) starting January 2020.
NOTE: Due to the size and format of these files, to view the data, please download the CSV file and open it with Notepad++ for complete document loading.
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143 Data Files
| Name | Format | Last Changed Sort ascending | Download | Explore |
|---|---|---|---|---|
| January 2025 – Historic Frequency Data | CSV | Download (CSV) | view | |
| December 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| November 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| October 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| August 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| September 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| July 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| June 2024 – Historic Frequency Data | CSV | Download (CSV) | view | |
| May 2022 - Historic Frequency Data | CSV | Download (CSV) | view | |
| May 2024 – Historic Frequency Data | CSV | Download (CSV) | view |
Additional Information
| Field | Value |
|---|---|
| Creator | National Grid Electricity System Operator |
| Date Created | November 5, 2019 at 11:50 AM (UTC+00:00) |
| Source | National Grid Electricity System Operator |
| Rights | NESO Open Data Licence |
| Update Frequency | Monthly |
cURL integration
# Get a list of dataset's resources
curl -L -s https://api.neso.energy/api/3/action/datapackage_show?id=system-frequency-data | grep path
# Get resources
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/7b01e945-0e5b-4b51-9a21-6dc0a6d422d7/download/fnew-2025-1.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/ac188a3c-9e52-40ce-8795-874e951327cb/download/fnew-2024-12.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/d83124cd-5f18-4bd3-b956-001914585d0f/download/fnew-2024-11.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/0c45a551-bda2-450c-9f41-b3185e643824/download/fnew-2024-10.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/e5a24d28-a344-4969-970a-ffda612931a7/download/fnew-2024-8.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/894b8dee-ad54-4f89-9f95-3f90661c3547/download/fnew-2024-9.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/5dd3bbc6-40d1-41d4-a8d0-cfefef11c099/download/fnew-2024-7.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/c19ba72b-64ee-41f8-ba2d-2fdb4f5c1550/download/fnew-2024-6.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/0a32dbfc-89e2-447d-a867-b10d5dbf3192/download/fnew-2022-5.csv
curl -L https://api.neso.energy/dataset/cb1cc925-ecd8-4406-b021-3a3f368196e1/resource/755fc810-1a55-4dc7-9692-84cc4a33fdcf/download/fnew-2024-5.csv