system-excursions

National Grid Electricity System Operator (ESO) is the transmission system operator, working to balance supply and demand in real time, as well as coordinating markets and auctions which ensure sufficient future supply, and exploring initiatives such as demand-side response measures to reduce peaks in electricity demand.

national-grid-eso

National Grid ESO

The National Grid Electricity System Operator (ESO) publishes an annual report on the performance of the National Electricity Transmission System in Great Britain and fulfils Transmission Licence Standard Condition C17: Transmission System Security Standard and Quality of Service. 

The Electricity Safety, Quality and Continuity Regulations 2002 permit variations of voltage not exceeding 10% above and below the nominal at voltages of 132kV and above and not exceeding 6% at lower voltages. Any voltage excursions in excess of 15 minutes will be reported. 

The Grid Code reflects these limits, and imposes a further constraint for the 400kV system in that voltages can only exceed +5% for a maximum of 15 minutes. Reportable excursions may be either at the HV and/or LV of a connection point with a Grid Code User. 

This dataset shows all reportable voltage excursions till date in 2019/2020 based on C17 reporting criteria.

GB System Voltage Excursions - FY1920

The National Grid Electricity System Operator (ESO) publishes annually report on the performance of the National Electricity Transmission System in Great Britain and fulfils Transmission Licence Standard Condition C17: Transmission System Security Standard and Quality of Service. 

The Electricity Safety, Quality and Continuity Regulations 2002 permit variations in frequency no exceeding 1% above and below 50Hz: a range of 49.5 to 50.5Hz. Any frequency excursions outside these limits for 60 seconds or more will be reported. 

System Frequency may exceed steady-state operational limits of 49.8Hz and 50.2Hz under fault conditions or when abnormal changes to operating conditions occur. Losses of generation between 1320 and 1800MW are considered abnormal and a maximum frequency change of 0.8Hz may occur, although the operation is managed so that the frequency should return within the lower statutory limit of 49.5Hz within 60 seconds. 

This dataset shows all reportable frequency excursions till date in 2019/2020 based on C17 reporting criteria.