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.
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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.
CVA generation in June 2021:
- Gas: 41%
- Nuclear: 21%
- Wind: 13%
- Interconnectors: 15%
The highest daily total generation for all fuel types was 673GWh on 29 June 2021.
Sum of CVA wind generation per settlement date
The graph below displays the wind generation that is registered in CVA only. The sum of metered volume is displayed by Settlement Day. GB wind generation can be registered in the Central Volume Allocation (CVA) arrangements, the Supplier Volume Allocation Arrangements or may not register at all.
On 11 June, 159GWh of electricity was generated from Wind, the highest daily total of the month. The average daily Wind generation during June was 79GWh.
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.
After having a negative minimum GSP Group Take in April and May 2021, the South Western (_L) GSP group had a minimum GSP Group Take of 35.41MWh during Settlement Period 30 on 12 June 2021 since 1 June 2021.
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.
- Output data for Maximum GSP Group metered volume supplied by SVA registered embedded generation for each GSP Group
In July, London (_C), Merseyside & North Wales (_D), Northern (_F), North Western (_G), South Wales (_K), Yorkshire (_M), South Scotland (_N) and North Scotland (_P) GSP Groups had their lowest maximum embedded generation metered volume in the past 12 months.
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.
The ADR graph shows two regions beyond the threshold variation of +/- 1.5%, South Wales (_K), and Yorkshire (_M).
The ADR for Eastern is now within the acceptable threshold variance after the GSP metering fault that we feel accounts for the ADR drop was fixed.
On the upward trend for the ADR in both South Wales and Yorkshire, investigation is still ongoing. Elexon will continue to update industry, and the relevant Elexon committees, on a regular basis, with feedback from committees taken into account in our investigations.
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.