Generation and Demand data from the Trading Operations Report
The page below details highlighted Generation and Demand data from the previous month. This data is acquired from BSC Agents and inputted to the Trading Operation Monitoring Analysis System (TOMAS) database.
To expand the graphs featured on the page, tap the double-headed arrow in the bottom right corner of the graph.
On this page
Generation
Sum of CVA Generation by fuel type per settlement date
BM Units that are registered in the Central Volume Allocation arrangements rather than through the Supplier Volume Allocation Arrangements have their metered data collected centrally by the Central Data Collection Agent. A single fuel type is assigned to each BM Unit and the sum of metered volume by fuel type is displayed by Settlement Day.
Highlights
Lower gas prices on January 11th and 12th, combined with increased energy demand due to the cold temperatures, led to a rise in gas-generated electricity as there was a reduction in other generation methods.
Minimum GSP Group Take based on SF run
The aim of the charts is to provide timely notification of any GSP Group that could become a net exporting GSP Group. The concern is that the underlying rules in the BSC implicitly assume that GSP Groups will import energy. Any deviation from this assumption results in the rules becoming unstable.
This chart provides a plot of the minimum value of GSP Group Take, (i.e. consumption) at the (Initial Settlement) SF run for each of the GSP Groups in each Settlement Day over the last 3 months. A negative GSP Group Take means the GSP Group is a net exporter.
Highlights
Electricity demand on January 11th surged due to the UK’s coldest temperatures since 2010, leading to a higher volume of energy entering the distribution system.
Maximum GSP Group metered volume supplied by SVA registered embedded generation for each GSP Group
This chart shows the daily sum of the SVA Registered Embedded Generation volume for each GSP Group for the day when that GSP experienced the highest volume of Embedded Generation during that month.
Highlights
Storm Éowyn caused widespread wind turbine shutdowns and infrastructure damage, leading to a sharp decline in embedded generation across GSP Groups D, F, G, K, L, M, N, and P. Additionally, lower-than-average wind speeds throughout January further reduced generation output in these regions.
Imports and Exports by GSP Group
Within each GSP Group, there will be multiple connections between the Transmission and Distribution Systems is known as a Grid Supply Point (GSP).
This graph displays the net Import or Export metered volume of each of these GSPs for each Settlement Period. The volumes are taken from the SF Settlement Run of the reporting month.
Highlights
There is no export within _E and _L with these being Solar Generated.
Percentage of Settlement Periods of GSP Export
Similar to the previous graph, this visualisation displays the percentage of Settlement Periods in the month the GSPs were exporting metered volume.
Highlights
There are no major highlights.
Demand
Annual Demand Ratio Values based on Settlement Run Type R2 or later
The chart below shows the ADR values for each GSP Group on a daily basis. ADR values have been calculated for the year ending on the dates indicated. To achieve the best trade-off between up to date information and accuracy the chart is based on Second Reconciliation (R2) Settlement Run data or from later Settlement Runs if these are available. Trends in the pattern of ADR may indicate issues with metering data within the GSP Groups.
Highlights
Elexon is investigating anomalies in Five GSP groups which are trending out of tolerance (with an ADR greater than 1.015) as of Settlement date 09 October 2024 (at the R2 Settlement run). These are GSP groups _G, _M, _F, _N and _D.
Elexon is compiling details of all completed and ongoing investigations in each GSP Group into single documents that will be shared with industry through the Trading Operations Report every month from December 2025 onwards. Elexon’s Assurance Team will produce and update similar documents for any future ADR anomalies so that industry is kept up-to-date with the progress of investigations.
Additionally, Elexon hosted an Annual Demand Ratio (ADR) and Group Correction Factor (GCF) workshop on 4th March 2025 in the Elexon offices to increase industry engagement.
An ADR value of greater than one indicates that:
- Overall recorded SVA consumption within the GSP Group is “under-accounted” (lower than the true volume); or
- Overall recorded SVA generation is “over-accounted” (higher than the true volume);
- Overall recorded consumption through CVA Grid Supply Point (GSP) and Distribution Connection System Point (DSCP) meters is “over-accounted”; or
- Overall recorded embedded CVA generation is “under-accounted”.
All BSC Parties and Party Agents operating within the affected GSP Groups, in both CVA and SVA markets, should be especially vigilant for any Settlement Error that may be contributing to the anomaly
About Annual Demand Ratio
Annual Demand Ratio provides a high-level understanding of the overall performance of the Non Half Hourly (NHH) Supplier Volume Allocation (SVA) market and identifies any significant under-/over-accounting of energy. Whilst the theoretical ‘ideal’ value of ADR is 1, variations of +/- 1.5% are to be expected due to inaccuracies in line loss estimates and a small usage of estimates at Final Reconciliation (RF) run. Values of less than 1 may result from the over-accounting of import energy in SVA, the under-accounting of export energy in SVA or under-accounting of Grid Supply Point (GSP) metering. Values of greater than 1 may result from the under-accounting of import energy in SVA, the over-accounting of export energy in SVA or over-accounting of GSP metering.